Coronavirus pandemic non-socio-political discussions

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RxCowboy

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COVID-19 Update: Friday, August 14th
Erratic reporting, declines, Masks with valves, New Zealand, Quarandreams and Numbers.

1. HCPs are expressing concerns over the new data reporting system citing erratic numbers from the new hospital reporting system that seem to differ from those being reported by the states. The same group shared examples of inappropriate allocation of resources based on these errors – such as 37k masks being routed to a school of 140 students. More information can be found at the COVID tracking project – (covidtracking.com), STAT reports, and in a letter published in the Washington post.

2. The Number of new cases for the week was down about 10% but testing was also down by about 10.5% so the reduced numbers may not indicate an actual reduction in cases.

3. Masks with valves or vents may be more comfortable but do little to actually prevent the spread of COVID. The valves and vents allow exhaled air to escape (that is their whole point) which allows the virus to escape as well, according to a new CDC report. This does not include N95 masks/filters - just vents.

4. New Zealand now has 17 new locally transmitted cases.

5. Quarandreams – that is the nick name given to the phenomenon of more vivid and stranger dreams people have been experiencing since the beginning of the pandemic. If you are experiencing more vivid dreams or dreams that are anxiety inducing, filled with trauma, or that include scenarios in which you are seeking solutions to some odd problem – you are not alone. Even dream recall (the ability to remember our dreams upon waking) is up by about 35%. While some are dreaming of post-apocalyptic scenarios, others are dreaming of increased social interactions and physical contact – things they have been deprived of since the pandemic began. According to a professor at MIT these are normal experiences in response to a time of increased stress. Reducing your news intake, developing healthy sleep routines, and reducing stress can help.

6. Numbers remained steady for the week with the CFR (case fatality rate) dropping from 3.24 to 3.15 in the US. Positivity rate (% of those who are tested and are positive) is 7.8%. And while the case count among children has increased, deaths in those under 18 remains very low at less than 0.1%

FINAL THOUGHTS: Another week has come and gone, and more strange things have happened in this whack-a-doodle year. Did you hear about the tongue eating parasite found in the fish? Or the hurricane forced winds that hit Iowa? If you don’t do yoga this may be a good time to start because this year demands agility and flexibility and resiliency. We have to laugh, or we would drown in our own tears. But we have made it another week because we are warriors. We have proven our grit yet again and if that doesn’t justify dessert, I don’t know what does. So, take the weekend off, kick your feet up, skip the news, eat ice cream, and watch a comedy – something that will make you laugh so hard you will worry about peeing your pants. You need a break, time to let your mind think about something else, time to let your nerves and stress levels have a little rest, time to renew and refresh and recharge so you will be ready for Monday.
 

oks10

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3. Masks with valves or vents may be more comfortable but do little to actually prevent the spread of COVID. The valves and vents allow exhaled air to escape (that is their whole point) which allows the virus to escape as well, according to a new CDC report. This does not include N95 masks/filters - just vents.
Yeah, this has seemed like such a "duh" thing to me. If the primary reason for wearing a mask is to prevent spread then why the heck would you wear a mask with vents/valves that allow air to escape unfiltered?...
 

RxCowboy

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Yeah, this has seemed like such a "duh" thing to me. If the primary reason for wearing a mask is to prevent spread then why the heck would you wear a mask with vents/valves that allow air to escape unfiltered?...
I did some digging on the N95 masks. The CDC does not recommend wearing the N95 respirators with valves in surgery. Following this logic, they would be the same as any other exhalation valve on a patient who was contagious. (I've posted this in response to my friend's blog, btw)

From the CDC:
"(N95) Respirators with exhalation valves can be used in a healthcare setting when it is not important to maintain a sterile field (an example of an acceptable practice would be when taking the temperature or blood pressure of a patient). Respirators with exhalation valves should not be used in situations where a sterile field is required (e.g., during an invasive procedure in an operating or procedure room) because the exhalation valve allows unfiltered exhaled air to escape into the sterile field."
 
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Yeah, this has seemed like such a "duh" thing to me. If the primary reason for wearing a mask is to prevent spread then why the heck would you wear a mask with vents/valves that allow air to escape unfiltered?...
No mask is perfect and many are improperly worn by people. But they do help deter the spead of infective droplets that you breathe in and if you are infected breathe out. Remember anyone you meet with symptoms or not...tested or not... may have the virus. Act accordingly.
 

RxCowboy

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COVID-19 Tuesday, August 18th
Saliva tests, temperature screenings, R0, incubation period and deaths.

1. A new saliva based rapid test has gotten EUA approval from the FDA. This could help speed up test results and increase their availability. The new test was created by Yale School of Public Health and is believed to be much easier and cheaper than current tests. The test reports sensitivity and specificity of 97% and 100% respectively which is much higher than many of the currently used tests so it should provide better accuracy. Yale has made the tests low cost (around $10) and open source so that other places can mimic their process.

2. Temperature screenings will not catch asymptomatic and pre-symptomatic carriers even though they are able to transmit the disease. It is worth noting that some people will get sick but never develop a fever or will develop a low-grade fever only.

3. Current R0 estimates are 3 – meaning each COVID positive person spreads it to 3 other people. Super spreaders are of course the exception. There is a working theory that only 20% of people actually spread it – but this is a working theory only that has not yet been peer reviewed and would warrant considerably more research.

4. A cross-sectional and forward follow-up study published in Science Advances suggests the incubation period may be slightly longer than previously thought. They found incubation periods of 7.76-14.28 days. Meaning the time from exposure to onset of illness could be a little longer than expected.

5. New deaths over the last 2 days have been in the 500’s, that is ½ what we have been seeing and a bit of good news.

FINAL THOUGHTS: I was changing out some light bulbs yesterday and I dropped one. I let out a little gasp in that way that you do and the world seemed to slip into slow-mo while I watched it fall and waited for the inevitable smashing of glass. Much to my surprise the smash didn’t come, in fact, the bulb hit the ground and bounced a bit before hitting the wall and coming to a rest. I was shocked. Apparently, somewhere along the way the world switched to plastic light bulbs and I completely missed it. I do remember when they announced “regular” light bulbs wouldn’t be available anymore. What I remember from that time was that people stockpiled them and there was great angst and upset and not being a light bulb connoisseur myself, I was unsure of why we were upset but I knew something unpleasant was happening. But here we are in the age of LED bulbs that you can drop, and they won’t break. You might say that light bulb moment caused me to have a light bulb moment. Change is hard. For some, it is much harder than others. Unwanted change is even harder. But sometimes really wonderful things come out of change, no matter the catalyst for the change. Sometimes, being forced to do things differently, brings about unexpectedly beautiful things. Today let’s look for the beauty in this situation, the moments of tender kindness, moments of neighbors helping neighbors or communities rallying together to support one another. The quiet moments of self-sacrifice. Moments of generosity, innovation, and discovery. Today, instead of looking at the ashes of what was, search for the beauty that will rise from those ashes.
 

RxCowboy

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Ginger Cameron, PhD

COVID-19 Tuesday, August 18th
Saliva tests, temperature screenings, R0, incubation period and deaths.

1. A new saliva based rapid test has gotten EUA approval from the FDA. This could help speed up test results and increase their availability. The new test was created by Yale School of Public Health and is believed to be much easier and cheaper than current tests. The test reports sensitivity and specificity of 97% and 100% respectively which is much higher than many of the currently used tests so it should provide better accuracy. Yale has made the tests low cost (around $10) and open source so that other places can mimic their process.

2. Temperature screenings will not catch asymptomatic and pre-symptomatic carriers even though they are able to transmit the disease. It is worth noting that some people will get sick but never develop a fever or will develop a low-grade fever only.

3. Current R0 estimates are 3 – meaning each COVID positive person spreads it to 3 other people. Super spreaders are of course the exception. There is a working theory that only 20% of people actually spread it – but this is a working theory only that has not yet been peer reviewed and would warrant considerably more research.

4. A cross-sectional and forward follow-up study published in Science Advances suggests the incubation period may be slightly longer than previously thought. They found incubation periods of 7.76-14.28 days. Meaning the time from exposure to onset of illness could be a little longer than expected.

5. New deaths over the last 2 days have been in the 500’s, that is ½ what we have been seeing and a bit of good news.

FINAL THOUGHTS: I was changing out some light bulbs yesterday and I dropped one. I let out a little gasp in that way that you do and the world seemed to slip into slow-mo while I watched it fall and waited for the inevitable smashing of glass. Much to my surprise the smash didn’t come, in fact, the bulb hit the ground and bounced a bit before hitting the wall and coming to a rest. I was shocked. Apparently, somewhere along the way the world switched to plastic light bulbs and I completely missed it. I do remember when they announced “regular” light bulbs wouldn’t be available anymore. What I remember from that time was that people stockpiled them and there was great angst and upset and not being a light bulb connoisseur myself, I was unsure of why we were upset but I knew something unpleasant was happening. But here we are in the age of LED bulbs that you can drop, and they won’t break. You might say that light bulb moment caused me to have a light bulb moment. Change is hard. For some, it is much harder than others. Unwanted change is even harder. But sometimes really wonderful things come out of change, no matter the catalyst for the change. Sometimes, being forced to do things differently, brings about unexpectedly beautiful things. Today let’s look for the beauty in this situation, the moments of tender kindness, moments of neighbors helping neighbors or communities rallying together to support one another. The quiet moments of self-sacrifice. Moments of generosity, innovation, and discovery. Today, instead of looking at the ashes of what was, search for the beauty that will rise from those ashes.
 

RxCowboy

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Ginger Cameron, PhD

COVID-19 Update: Wednesday, August 19th
Immunity, lower case counts, contact tracing, thyroid issues, and the flu.

1. An animal study published in PubMed on Aug. 14th had positive results indicating that once exposed you may develop immunity. Monkeys were exposed to COVID, after the initial infection cleared, they were re-exposed and viral loads were lower. While this doesn’t tell us how long we may be immune or how strong that immunity may be, it is a nice indication that immunity is possible.

2. For the third consecutive day new case numbers have been below 50k. Considering in July we had multiple days at 70k+ this is a small victory.

3. Contact tracing between states is nearly impossible. Events like casinos opening, summer camps and holiday travel have revealed that our ability to contact trace large exposures that involve people from multiple states or who are traveling to and from public events is nearly impossible. Because of this, people may be exposed in these places, then travel home unknowingly taking the virus with them.

4. The thyroid is the latest organ to be identified as negatively impacted by COVID according to a study published in The Lancet Diabetes and Endocrinology. This study looked at critically ill patients only. It also noted that pre-existing thyroid disorders do not appear to increase risk. It is important to keep in mind that not all people experience all possible effects.

5. Public Health professionals are hopeful people will get their flu vaccines this year as you do not want both COVID and the flu and there is some evidence that the flu vaccine may provide a little protection from COVID or at least reduce severity. It is important to know a few things about the flu vaccine, first, not everyone can take it so be sure to disclose allergies to your HCP, second it takes 2 weeks for the vaccine to take effect, so if you are exposed to the flu prior to getting it or for 2 weeks after you are still as vulnerable as if you didn’t get the vaccine, third it is a dead virus (except the nasal one which hasn’t been used in a while) so it cannot give you the flu BUT it does illicit an immune response (which is the whole point) so your body goes into full on attack mode of the dead virus – with a guaranteed win because the virus is dead – but that may mean you feel a little under the weather for a day or two while that process works itself out. This is typically seen in the form of fatigue and mild muscle aches. Some people experience this, some don’t.

FINAL THOUGHTS: Today I want to encourage you to take a deep breath, then exhale slowly. Let out the stress, the worry and any fear. Look around, re-assess your personal situation. Then use all that you know about your risk, the virus and how to reduce your risk to get back to some version of normal, some sense of routine because isolation, loneliness and anxiety can be just as harmful as the virus. So many of us are running on empty, stress levels are high, life is topsy-turvy and there are lots of unknowns. We have to cut each other some slack, but we also need to work towards getting back to some version of our normal routine. It can help. Do what is best for you and your family unapologetically. Respect and love others enough to let them do the same. Then keep your eyes on the good news, and the small wins, because worrying doesn’t add days to your life and we are winning, even if it doesn’t always feel that way.
 

RxCowboy

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COVID-19 Update: Thursday, August 20
Convalescent plasma, masks are working, no reporting for schools, and misinformation.

1. Convalescent plasma (where we use the antibodies from people who have had and recovered from COVID to treat people with COVID) is not getting FDA approval at this time. The science hasn’t been strong enough to support that it works.

2. As more and more places wear masks, our numbers are moving in the right direction! This is great news.

3. There is no centralized tracking of school-related outbreaks and some states are opting not to make that information public.

4. A study published in JAMA yesterday tested 64 samples of breast milk from women who were positive for COVID to see if there were transmittable levels of the virus in the breast milk – there was not.

5. According to the American Journal of Tropical Medicine and Hygiene, misinformation is pretty prevalent and not just in the US. They analyzed 2,311 reports etc. in 25 languages from over 87 countries and found that roughly 1800 of them were misinformation. Be leery.

FINAL THOUGHTS: Some days are hard. Some days are harder yet. In those days, we must trust that we are equipped and able to manage the battle before us. We have to lean on others and allow them to do the same, but when the day is done, we are the ones who have to walk into the fire. Slow deep breaths help. Asking for support and help when you need it is critical. Offering a hand to those who are struggling is love. If today is a harder day, reach out and let someone support you. If today is only hard, lend a hand to those who struggle. And breathe, slow, deep, cleansing breaths. You have done so much and worked so hard. It’s ok to be tired. It’s ok to be weary. It’s ok to be worried or nervous, or frustrated or over it, or even angry. Slow, deep breaths. It’s ok.
 

RxCowboy

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Seven months later, what we know about Covid-19 — and the pressing questions that remain
By ANDREW JOSEPH @DrewQJoseph, HELEN BRANSWELL @HelenBranswell, and ELIZABETH COONEY @cooney_lizAUGUST 17, 2020Reprints

The “before times” seem like a decade ago, don’t they? Those carefree days when hugging friends and shaking hands wasn’t verboten, when we didn’t have to reach for a mask before leaving our homes, or forage for supplies of hand sanitizer. Oh, for the days when social distancing wasn’t part of our vernacular.

In reality, though, it’s only been about seven months since the world learned a new and dangerous coronavirus was in our midst. In the time since Chinese scientists confirmed the rapidly spreading disease in Wuhan was caused by a new coronavirus and posted its genetic sequence on line, an extraordinary amount has been learned about the virus, SARS-CoV-2, the disease it causes, Covid-19, and how they affect us.

Here are some of the things we have learned, and some of the pressing questions we still need answered.

What we know
Covid and kids: It’s complicated


Early in the pandemic, it looked like there was a silver lining to the disease cloud sweeping across the world. Children, it seemed, didn’t develop the severe symptoms that were sending adults to hospitals struggling for breath, and they very rarely died. It even seemed that kids didn’t contract the disease at the same rates as adults did.

But everything Covid is complex, and kids are no exception. While deaths among children and teens remain low, they are not invulnerable. And they probably contribute to transmission of SARS-CoV-2, though how much remains unclear.

We’ve learned younger children and teenagers shouldn’t be lumped together when it comes to Covid. Teens seem to shed virus — emit it from their throats and nasal passages — at about the same rates as adults. Kids under 5 have high levels of virus in their respiratory tracts, but it’s still not clear how much they spread it or why they don’t develop symptoms as often as adults do.

A recently published report from a Georgia sleep-away camp shows how quickly the virus can spread among kids. The camp had to be closed within 10 days of starting its orientation for camp staffers, because within days of children arriving, kids and staff started getting sick. (The campers ranged in age from 6 to 19.) The camp did not require campers to wear face masks.

A recent report on Covid infections in children from the Centers for Disease Control and Prevention showed that while they remain low, U.S. hospitalization rates for Covid-19 in children have risen since the pandemic started. And one in three children hospitalized with the disease ends up in intensive care. The highest rate of hospitalizations in children was among those under 2 years of age.

Black and Latino children were hospitalized at higher rates than white children. And like adults, children with other health conditions — obesity, chronic lung diseases, or infants who were born premature — are at higher risk than otherwise healthy children.

Perhaps most alarmingly, it’s become clear that a small proportion of children infected with Covid-19 go on to develop a condition where multiple organs come under attack from their own immune system. Called multisystem inflammatory syndrome in children or MIS-C, this condition seems to occur about two to four weeks after Covid-19 infection. Most children who develop this syndrome recover.

There are safer settings, and more dangerous settings

Research has coalesced on a few key points about what types of setting increase the risk that an infectious person will pass the virus to others.

Essentially, the closer you are to someone infectious and the longer you’re in contact with them, the more likely you are to contract the virus, which helps explain why so much transmission occurs within households. Being indoors is worse, particularly in rooms without sufficient ventilation; the more air flow, the faster the virus gets diluted. Everyday face coverings reduce the amount of virus projected, but aren’t total blockades.

Loud talking, heavy breathing, singing, and screaming expel more virus, which is why experts point to nightclubs and gyms as risky businesses to be open. (That’s not to say it’s impossible to catch the virus while having a quiet conversation with someone outside — it’s just less likely.)

The reason having prolonged, proximate contact with someone is riskier is in part because there is a threshold level of virus you need to be exposed to to become infected. (More on this later.) Also, one hypothesis for why some people get so sick is that they are exposed to higher “doses” of virus.

Researchers are also finding that some relatively small proportion of infected people — maybe 10% to 20% — are driving some 80% of new cases, often through “superspreading” events in indoor settings like bars, meat processing plants, and homes. Whether such transmission occurs depends on a host of variables: how many people are in a given place, what the ventilation in the room is like, and, of course, whether someone with infectious Covid-19 is there. Some people might shed more virus than others, and people are more or less likely to spread the virus during different points in their infection. Evidence suggests that contagiousness spikes in the days before people who will go on to show symptoms start feeling sick.

People can test positive for a long time after they recover. It doesn’t matter

There was a lot of angst a few months ago about some people who had seemingly recovered from Covid-19 infections continuing to test positive for the virus for weeks. Were they infectious? Should recommendations be changed for how long infected people should be isolated?

It turns out it is an issue of testing. Most testing is conducted using a platform called PCR — polymerase chain reaction — that looks for tiny fragments of the SARS-CoV-2 virus. But the test can’t tell if those sections of genetic code are part of actual viruses that can infect someone else, or fragments of viruses that are absolutely no threat.

It’s clear now that people who had mild or uncomplicated infections shed active virus for somewhere up to 10 days after their symptoms started. (“Severely ill or immunocompromised patients do shed infectious virus for longer,” said Malik Peiris, a coronavirus expert at Hong Kong University.)

The weeks and weeks of positive tests — like those that prevented this woman in Quebec from cuddling her infant son for 55 days — don’t tell us that these people are still a risk to others. “In fact, we know that they are not infectious for that long,” said Maria Van Kerkhove, the World Health Organization’s leading coronavirus expert.

After the storm, there are often lingering effects

Name a body part or system and Covid-19 has left its fingerprints there. We know this: Unusually sticky blood can clog vessels on the way to the heart and inside the brain and lungs of infected people, causing heart attacks, strokes, and deadly pulmonary embolisms. There are growing worries that these and other health effects will be long-lasting.

Heart: The hyperinflammation of an immune response triggered by the virus can weaken heart muscles so much that even young people who had mild infections may be at risk for future heart failure, cardiac MRIs in Germany indicate. More immediately, some people have chest pain or feel like their hearts are racing as they recover from the infection. And college athletes are no exception

Brain: People whose first Covid-19 symptom might have been losing their sense of smell and taste may find their anosmia persists. Headaches and dizziness are common. Mood disorders such as anxiety, depression, and PTSD follow in the wake of infection, and the mental confusion called “Covid fog” leaves people searching for words, struggling with simple math, or simply trying to think.

Peripheral nervous system: In Italy, three Covid-19 patients experienced myasthenia gravis, an autoimmune disorder that results in faulty communication between nerves and muscles. Doctors also worry about demyelination, in which the protective coating of nerve cells is attacked by the immune system, causing weakness, numbness, and tingling. In some cases it can spur psychosis and hallucinations. Some patients have Guillain-Barre syndrome, a rare autoimmune disease that interferes with nerve signals, leading to abnormal sensations, weakness, and sometimes paralysis.

‘Long-haulers’ don’t feel like they’ve recovered

They have a name, a growing social media presence, and a problem. They are the “long-haulers,” people who have survived their Covid-19 infections but feel a long way from normal. We know they’re out there, but we don’t know how many, why their symptoms persist, and what happens next.

In July, a survey conducted by the CDC found that 35% of people who tested positive for SARS-CoV-2 and had symptoms of Covid-19 — cough, fatigue, or shortness of breath — but were not hospitalized had not returned to their previous health two to three weeks later. Among those between 18 and 34 years old who had no previous chronic conditions, 20% felt prolonged signs of illness.

The National Heart, Lung, and Blood Institute has launched an observational study to track the long-term effects of Covid-19, aiming to follow 3,000 patients six months after being discharged from 50 hospitals.

Mount Sinai Health System in New York City opened a Center for Post-Covid Care in May to treat long-haulers. David Putrino, director of rehabilitation innovation there, has suggested dysautonomia — when heart rate, blood pressure, and body temperature are disjointed —could be to blame for prolonged and distressing symptoms. Why Covid-19 would cause this isn’t known, nor is the best treatment.

Vaccine development can be accelerated. A lot

The world still doesn’t have a vaccine that has been shown to be protective against Covid-19, though China and Russia have issued emergency use licenses for partially tested vaccines.

But an extraordinary amount of progress toward Covid-19 vaccines has been made, in record time. Trials have been compressed and overlapped, with manufacturers running Phase 1/2 trials in some cases and Phase 2/3 trials in others.

Meanwhile, they’ve been building out manufacturing capacity to be able to produce hundreds of millions of doses and have started production, even before finding out whether their vaccine candidate actually works. This work is being done with substantial financial support of governments, the Bill and Melinda Gates Foundation, and CEPI, the Coalition for Epidemic Preparedness Innovations.

It’s called “at risk” production — and the term is apt. If some of these vaccines don’t work, that output will have to be junked. But if Phase 3 trials show they do work, deployment could begin as soon as the Food and Drug Administration, or a regulator in another country, approves any of these vaccines.

That means vaccination with fully approved vaccines could begin as soon as about a year after the discovery of the new virus. This constitutes a revolution in vaccine development.

People without symptoms can spread the virus

Discussing asymptomatic cases of Covid-19 automatically raises some headache-inducing semantic issues. Some people are truly asymptomatic throughout their infections, but the word is often also used to describe people who are presymptomatic — those who will show symptoms but haven’t yet. Other people don’t show classic Covid-19 symptoms — fever, cough, loss of smell — but just feel kinda crappy for a day. Where do they fit in?

Whatever group you’re talking about, there are some key implications for the pandemic, and trying to rein it in. One: Some percentage of infected people — roughly 20%, according to one recent review, though other studies have produced higher estimates — do not show symptoms at all. And two: Whether or not someone is asymptomatic or presymptomatic, they can still spread the virus (though whether they spread it as efficiently as people with symptoms is still unknown). That is why public health campaigns have been stressing distancing, masks, and hand hygiene for everyone, not just people who feel sick. Once you do start showing symptoms and try to restrict contact with others, it is too late to prevent spread.

Mutations to the virus haven’t been consequential

Coronaviruses in general do not mutate very quickly compared to other viral families. This is a good thing: The leading vaccine candidates, for example, are based on SARS-CoV-2’s genetic sequence, so theoretically a major change in that lineup could hinder the effectiveness of any vaccine. So far, that doesn’t seem to have happened.

Still, scientists have noticed smaller changes in the genome. The one that has gotten the most attention was one swap in the “letters” that make up the virus’ RNA, which created the “G variant.” The switch happened early in the pandemic, and the G variant has since become dominant around the world. Scientists haven’t been able to figure out, however, whether the G variant is outcompeting its predecessor — perhaps it’s more contagious? — or if that’s just chance. And so far, they haven’t landed on evidence that people who contract the G variant get more or less sick than those infected by the other variant. It could just be a mutation that’s like changing your T-shirt from navy blue to royal blue — an aesthetic difference, but something pretty neutral.

Viruses on surfaces probably aren’t the major transmission route

Throughout the spring, you could barely find hand sanitizer. Fears that viruses lurking on surfaces could infect us with Covid-19 turned most of us into zealous surface cleaners. Some people went so far as to quarantine their mail, not touching it for days as they waited for potential lingering viruses to die.

The general consensus now is that “fomites” — germs on surfaces — aren’t the major transmission route for Covid-19. Van Kerkhove of WHO said there hasn’t been a case recorded where it’s clear someone was infected by fomites alone.

(In the real world, someone in close enough contact with an infected person to become infected will likely have encountered viruses on surfaces and virus-laced droplets and maybe even small, aerosol-sized particles containing the virus that have been expelled by coughing, singing, or speaking. Teasing out of that situation which route of transmission triggered infection may be impossible to do.)

But it’s clear from lots of studies that surfaces around infected people can be contaminated with viruses and the viruses can linger. Cleaning surfaces and being prudent about hand hygiene is a risk-lowering step people can take, public health officials agree.

What we don’t know
People seem to be protected from reinfection, but for how long?


The thinking is that a case of Covid-19, like other infections, will confer some immunity against reinfection for some amount of time. But researchers won’t know exactly how long that protection lasts until people start getting Covid-19 again.

So far, despite some anecdotal reports, scientists have not confirmed any repeat Covid-19 cases.

All that supports the notion that Covid-19 acts like other viral infections, including illnesses caused by other coronaviruses. Researchers are finding that most infected people mount an immune response involving both antibodies and immune cells that clears the virus, and that persists for some amount of time. Reports of waning antibody levels incited some concern that perhaps protection to SARS-CoV-2 might not last very long, with big implications for the frequency of required vaccine boosts. But immunologists have pointed out that antibodies for other viruses wane as well; their levels surge upon re-exposure to the pathogen and they can still halt reinfection.

Researchers don’t know for sure what level of antibodies are required to block the virus from gaining a toehold in cells, and what role pathogen-fighting T cells might have in fending off an infection. People who recover from Covid-19 also produce varying levels of antibodies — it’s possible people who generate a weaker initial immune response might not be protected for as long from reinfection.

“We don’t know for how long that immune response lasts,” the WHO’s Van Kerkhove said last week. “We don’t know how strong it is.”

What happens if or when people start having subsequent infections?

Given that most respiratory viruses are not “one-and-done” infections — they don’t induce life-long immunity in the way a virus like measles does — there is a reasonable chance that people could have more than one infection with Covid-19.

Experience with human coronaviruses — which mostly cause colds — supports that idea. A study in the Netherlands followed people for decades, measuring their antibodies to four human coronaviruses at regular intervals and looking for changes that would indicate a new infection. The scientists found that reinfection could occur within a year of the first infection. (The study is a preprint, meaning it hasn’t yet been through the peer review process.)

Some scientists have theorized that on subsequent infections, immune systems might mount quicker responses to Covid-19, leading to milder infections. If that’s true, the SARS-CoV-2 virus might transition into a less daunting threat over time. But it’s still a big unknown. “We don’t know,” Van Kerkhove said. “I don’t want to speculate.”

How much virus does it take to get infected?

Whether you become infected or not when you encounter a pathogen isn’t just a question of whether you’re susceptible or immune. It depends on how much of the virus (or bacterium) you encounter.

And the amount capable of tipping the balance is what’s known as the minimum infectious dose. Some pathogens have a low infectious dose. For example, it doesn’t take a lot of E. coli 0157, a dangerous bacterium transmitted in food, to make someone sick.

How big a dose of SARS-CoV-2 does it take to infect most people? It’s one of the burning questions in SARS-CoV-2 research, said Angela Rasmussen, a coronavirus expert at Columbia University. “We don’t know the amount that is required to cause an infection, but it seems that it’s probably not a really, really small amount, like measles.”

How many people have been infected?

There have been 21 million confirmed cases of Covid-19 around the world, and 5.3 million in the United States. Far more people than that have actually had the virus.

Problems with testing, and its limited availability, have contributed to that gap, as has the fact that some people have such mild or no symptoms that they don’t know they’re infected. But researchers don’t know just how big of a gulf they’re dealing with — how much spread they’ve missed.

“Serosurveys” — which rely on testing for the level of SARS-CoV-2 antibodies in a community — are starting to help fill in some knowledge. A recent CDC study of 10 cities and states estimated that in most places, the true number of infections was some 10 times higher than the number of confirmed cases.

Still, that leaves perhaps 20% of people, even in hard-hit communities, with potential immunity to Covid-19. That means that herd immunity — the point at which so many people are immune that the virus can’t circulate — remains far off even in areas that have suffered severe outbreaks.

It’s not clear why some people get really sick, and some don’t

The sheer range of outcomes for people who get Covid-19 — from a truly asymptomatic case, to mild symptoms, to moderate disease leading to months-long complications, to death — has befuddled infectious disease researchers.

There are some clear factors for who faces higher risks of getting severely ill: older people, as well as people with conditions ranging from cancer to obesity to sickle cell disease.

But scientists have postulated that a host of other underlying factors could help dictate why most healthy 30-year-olds shake off the virus after a couple days and some get severely ill. Researchers are studying genetic differences in patients, while others are looking at blood type.

Recent studies have pointed to another potential player. Perhaps up to half the population has immune-system T cells that were initially generated in response to an infection by one of the common cold-causing coronaviruses but that can recognize SARS-CoV-2 as well. These “cross-reactive” T cells could help give the immune system the boost it needs to stave off serious symptoms, but researchers don’t know for sure what role, if any, they actually play.

Correction: An earlier version of this story misstated the cause of myasthenia gravis, an autoimmune disorder that results in faulty communication between nerves and muscles.

About the Authors

Andrew Joseph
General Assignment Reporter
Andrew is a general assignment reporter.
andrew.joseph@statnews.com
@DrewQJoseph

Helen Branswell
Senior Writer, Infectious Disease
Helen covers issues broadly related to infectious diseases, including outbreaks, preparedness, research, and vaccine development.
@HelenBranswell

Elizabeth Cooney
General Assignment Reporter
Liz is a general assignment reporter.
elizabeth.cooney@statnews.com
@cooney_liz
 

RxCowboy

Has no Rx for his orange obsession.
A/V Subscriber
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Ginger Cameron, PhD

COVID-19 Update: Friday, August 21
Llamas, Numbers, shifting back to the CDC, antibody testing, and female leadership.

1. According to the NIH, the answer may lie with llamas. Well, at least part of it. Researchers have isolated antibodies from a llama that they used to create antibodies that could block the virus from entering cells in a petri dish. Obviously not something that is going to roll out tomorrow but worth exploring further.

2. The US added 330k new cases this week but deaths were down, and the CFR is down to 3.09% well below the global CFR of 3.48%. There are now 504k reported cases among children ages 0-19 according to the CovKid project but deaths remain low at 109 total and 1100 in the ICU. Test positivity rate is averaging 7% nationally which is down slightly from prior weeks and total US deaths attributed to COVID were 8.1% last week.

3. According to CIDRAP, an interview in Medical News Today and the Wall Street Journal, the CDC is taking back over the collection of hospital data. You may recall that was shifted to a privately owned source. Reportedly they are making arrangements to shift it back to the CDC so stayed tuned for more on that.

4. Antibody testing is best done 3-4 weeks after infection according to the Infectious Diseases Society of America. Test too soon and the antibodies will not show up, test to late and they will have started to fade. Also, worth noting in the testing department, as we try to conduct more testing it increases bottlenecking from the labs as most labs are analyzing tests at maximum capacity.

5. Two new studies are reporting that countries run by women and states in the US governed by women are managing the pandemic better than those run by men. The general reason for this seems to be that women were more decisive and acted sooner than their male counterparts. You can read some of these studies at Social Science Research Network and the Journal of Applied Psychology.

FINAL THOUGHTS: Friday has finally arrived, and we have made it another week. It is time to step away and give yourself a break from the news and social media. Time to renew, refresh, rest, and distract ourselves with other things, more important things. Tonight may be a great night for a movie – preferably something funny because we could all use a laugh. So, round up some people you are safe with, pop some popcorn and then Netflix and chill. I’ll see you back on Monday.
 

wrenhal

Territorial Marshal
Aug 11, 2011
9,835
4,066
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Ginger Cameron, PhD

COVID-19 Tuesday, August 18th
Saliva tests, temperature screenings, R0, incubation period and deaths.

1. A new saliva based rapid test has gotten EUA approval from the FDA. This could help speed up test results and increase their availability. The new test was created by Yale School of Public Health and is believed to be much easier and cheaper than current tests. The test reports sensitivity and specificity of 97% and 100% respectively which is much higher than many of the currently used tests so it should provide better accuracy. Yale has made the tests low cost (around $10) and open source so that other places can mimic their process.

2. Temperature screenings will not catch asymptomatic and pre-symptomatic carriers even though they are able to transmit the disease. It is worth noting that some people will get sick but never develop a fever or will develop a low-grade fever only.

3. Current R0 estimates are 3 – meaning each COVID positive person spreads it to 3 other people. Super spreaders are of course the exception. There is a working theory that only 20% of people actually spread it – but this is a working theory only that has not yet been peer reviewed and would warrant considerably more research.

4. A cross-sectional and forward follow-up study published in Science Advances suggests the incubation period may be slightly longer than previously thought. They found incubation periods of 7.76-14.28 days. Meaning the time from exposure to onset of illness could be a little longer than expected.

5. New deaths over the last 2 days have been in the 500’s, that is ½ what we have been seeing and a bit of good news.

FINAL THOUGHTS: I was changing out some light bulbs yesterday and I dropped one. I let out a little gasp in that way that you do and the world seemed to slip into slow-mo while I watched it fall and waited for the inevitable smashing of glass. Much to my surprise the smash didn’t come, in fact, the bulb hit the ground and bounced a bit before hitting the wall and coming to a rest. I was shocked. Apparently, somewhere along the way the world switched to plastic light bulbs and I completely missed it. I do remember when they announced “regular” light bulbs wouldn’t be available anymore. What I remember from that time was that people stockpiled them and there was great angst and upset and not being a light bulb connoisseur myself, I was unsure of why we were upset but I knew something unpleasant was happening. But here we are in the age of LED bulbs that you can drop, and they won’t break. You might say that light bulb moment caused me to have a light bulb moment. Change is hard. For some, it is much harder than others. Unwanted change is even harder. But sometimes really wonderful things come out of change, no matter the catalyst for the change. Sometimes, being forced to do things differently, brings about unexpectedly beautiful things. Today let’s look for the beauty in this situation, the moments of tender kindness, moments of neighbors helping neighbors or communities rallying together to support one another. The quiet moments of self-sacrifice. Moments of generosity, innovation, and discovery. Today, instead of looking at the ashes of what was, search for the beauty that will rise from those ashes.
I still don't think they've gotten LED bulbs to mimic incandescents properly yet. The brightness without being harsh just isn't there. Oh well.

Sent from my Moto Z (2) using Tapatalk
 

wrenhal

Territorial Marshal
Aug 11, 2011
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Seven months later, what we know about Covid-19 — and the pressing questions that remain
By ANDREW JOSEPH @DrewQJoseph, HELEN BRANSWELL @HelenBranswell, and ELIZABETH COONEY @cooney_lizAUGUST 17, 2020Reprints

The “before times” seem like a decade ago, don’t they? Those carefree days when hugging friends and shaking hands wasn’t verboten, when we didn’t have to reach for a mask before leaving our homes, or forage for supplies of hand sanitizer. Oh, for the days when social distancing wasn’t part of our vernacular.

In reality, though, it’s only been about seven months since the world learned a new and dangerous coronavirus was in our midst. In the time since Chinese scientists confirmed the rapidly spreading disease in Wuhan was caused by a new coronavirus and posted its genetic sequence on line, an extraordinary amount has been learned about the virus, SARS-CoV-2, the disease it causes, Covid-19, and how they affect us.

Here are some of the things we have learned, and some of the pressing questions we still need answered.

What we know
Covid and kids: It’s complicated


Early in the pandemic, it looked like there was a silver lining to the disease cloud sweeping across the world. Children, it seemed, didn’t develop the severe symptoms that were sending adults to hospitals struggling for breath, and they very rarely died. It even seemed that kids didn’t contract the disease at the same rates as adults did.

But everything Covid is complex, and kids are no exception. While deaths among children and teens remain low, they are not invulnerable. And they probably contribute to transmission of SARS-CoV-2, though how much remains unclear.

We’ve learned younger children and teenagers shouldn’t be lumped together when it comes to Covid. Teens seem to shed virus — emit it from their throats and nasal passages — at about the same rates as adults. Kids under 5 have high levels of virus in their respiratory tracts, but it’s still not clear how much they spread it or why they don’t develop symptoms as often as adults do.

A recently published report from a Georgia sleep-away camp shows how quickly the virus can spread among kids. The camp had to be closed within 10 days of starting its orientation for camp staffers, because within days of children arriving, kids and staff started getting sick. (The campers ranged in age from 6 to 19.) The camp did not require campers to wear face masks.

A recent report on Covid infections in children from the Centers for Disease Control and Prevention showed that while they remain low, U.S. hospitalization rates for Covid-19 in children have risen since the pandemic started. And one in three children hospitalized with the disease ends up in intensive care. The highest rate of hospitalizations in children was among those under 2 years of age.

Black and Latino children were hospitalized at higher rates than white children. And like adults, children with other health conditions — obesity, chronic lung diseases, or infants who were born premature — are at higher risk than otherwise healthy children.

Perhaps most alarmingly, it’s become clear that a small proportion of children infected with Covid-19 go on to develop a condition where multiple organs come under attack from their own immune system. Called multisystem inflammatory syndrome in children or MIS-C, this condition seems to occur about two to four weeks after Covid-19 infection. Most children who develop this syndrome recover.

There are safer settings, and more dangerous settings

Research has coalesced on a few key points about what types of setting increase the risk that an infectious person will pass the virus to others.

Essentially, the closer you are to someone infectious and the longer you’re in contact with them, the more likely you are to contract the virus, which helps explain why so much transmission occurs within households. Being indoors is worse, particularly in rooms without sufficient ventilation; the more air flow, the faster the virus gets diluted. Everyday face coverings reduce the amount of virus projected, but aren’t total blockades.

Loud talking, heavy breathing, singing, and screaming expel more virus, which is why experts point to nightclubs and gyms as risky businesses to be open. (That’s not to say it’s impossible to catch the virus while having a quiet conversation with someone outside — it’s just less likely.)

The reason having prolonged, proximate contact with someone is riskier is in part because there is a threshold level of virus you need to be exposed to to become infected. (More on this later.) Also, one hypothesis for why some people get so sick is that they are exposed to higher “doses” of virus.

Researchers are also finding that some relatively small proportion of infected people — maybe 10% to 20% — are driving some 80% of new cases, often through “superspreading” events in indoor settings like bars, meat processing plants, and homes. Whether such transmission occurs depends on a host of variables: how many people are in a given place, what the ventilation in the room is like, and, of course, whether someone with infectious Covid-19 is there. Some people might shed more virus than others, and people are more or less likely to spread the virus during different points in their infection. Evidence suggests that contagiousness spikes in the days before people who will go on to show symptoms start feeling sick.

People can test positive for a long time after they recover. It doesn’t matter

There was a lot of angst a few months ago about some people who had seemingly recovered from Covid-19 infections continuing to test positive for the virus for weeks. Were they infectious? Should recommendations be changed for how long infected people should be isolated?

It turns out it is an issue of testing. Most testing is conducted using a platform called PCR — polymerase chain reaction — that looks for tiny fragments of the SARS-CoV-2 virus. But the test can’t tell if those sections of genetic code are part of actual viruses that can infect someone else, or fragments of viruses that are absolutely no threat.

It’s clear now that people who had mild or uncomplicated infections shed active virus for somewhere up to 10 days after their symptoms started. (“Severely ill or immunocompromised patients do shed infectious virus for longer,” said Malik Peiris, a coronavirus expert at Hong Kong University.)

The weeks and weeks of positive tests — like those that prevented this woman in Quebec from cuddling her infant son for 55 days — don’t tell us that these people are still a risk to others. “In fact, we know that they are not infectious for that long,” said Maria Van Kerkhove, the World Health Organization’s leading coronavirus expert.

After the storm, there are often lingering effects

Name a body part or system and Covid-19 has left its fingerprints there. We know this: Unusually sticky blood can clog vessels on the way to the heart and inside the brain and lungs of infected people, causing heart attacks, strokes, and deadly pulmonary embolisms. There are growing worries that these and other health effects will be long-lasting.

Heart: The hyperinflammation of an immune response triggered by the virus can weaken heart muscles so much that even young people who had mild infections may be at risk for future heart failure, cardiac MRIs in Germany indicate. More immediately, some people have chest pain or feel like their hearts are racing as they recover from the infection. And college athletes are no exception

Brain: People whose first Covid-19 symptom might have been losing their sense of smell and taste may find their anosmia persists. Headaches and dizziness are common. Mood disorders such as anxiety, depression, and PTSD follow in the wake of infection, and the mental confusion called “Covid fog” leaves people searching for words, struggling with simple math, or simply trying to think.

Peripheral nervous system: In Italy, three Covid-19 patients experienced myasthenia gravis, an autoimmune disorder that results in faulty communication between nerves and muscles. Doctors also worry about demyelination, in which the protective coating of nerve cells is attacked by the immune system, causing weakness, numbness, and tingling. In some cases it can spur psychosis and hallucinations. Some patients have Guillain-Barre syndrome, a rare autoimmune disease that interferes with nerve signals, leading to abnormal sensations, weakness, and sometimes paralysis.

‘Long-haulers’ don’t feel like they’ve recovered

They have a name, a growing social media presence, and a problem. They are the “long-haulers,” people who have survived their Covid-19 infections but feel a long way from normal. We know they’re out there, but we don’t know how many, why their symptoms persist, and what happens next.

In July, a survey conducted by the CDC found that 35% of people who tested positive for SARS-CoV-2 and had symptoms of Covid-19 — cough, fatigue, or shortness of breath — but were not hospitalized had not returned to their previous health two to three weeks later. Among those between 18 and 34 years old who had no previous chronic conditions, 20% felt prolonged signs of illness.

The National Heart, Lung, and Blood Institute has launched an observational study to track the long-term effects of Covid-19, aiming to follow 3,000 patients six months after being discharged from 50 hospitals.

Mount Sinai Health System in New York City opened a Center for Post-Covid Care in May to treat long-haulers. David Putrino, director of rehabilitation innovation there, has suggested dysautonomia — when heart rate, blood pressure, and body temperature are disjointed —could be to blame for prolonged and distressing symptoms. Why Covid-19 would cause this isn’t known, nor is the best treatment.

Vaccine development can be accelerated. A lot

The world still doesn’t have a vaccine that has been shown to be protective against Covid-19, though China and Russia have issued emergency use licenses for partially tested vaccines.

But an extraordinary amount of progress toward Covid-19 vaccines has been made, in record time. Trials have been compressed and overlapped, with manufacturers running Phase 1/2 trials in some cases and Phase 2/3 trials in others.

Meanwhile, they’ve been building out manufacturing capacity to be able to produce hundreds of millions of doses and have started production, even before finding out whether their vaccine candidate actually works. This work is being done with substantial financial support of governments, the Bill and Melinda Gates Foundation, and CEPI, the Coalition for Epidemic Preparedness Innovations.

It’s called “at risk” production — and the term is apt. If some of these vaccines don’t work, that output will have to be junked. But if Phase 3 trials show they do work, deployment could begin as soon as the Food and Drug Administration, or a regulator in another country, approves any of these vaccines.

That means vaccination with fully approved vaccines could begin as soon as about a year after the discovery of the new virus. This constitutes a revolution in vaccine development.

People without symptoms can spread the virus

Discussing asymptomatic cases of Covid-19 automatically raises some headache-inducing semantic issues. Some people are truly asymptomatic throughout their infections, but the word is often also used to describe people who are presymptomatic — those who will show symptoms but haven’t yet. Other people don’t show classic Covid-19 symptoms — fever, cough, loss of smell — but just feel kinda crappy for a day. Where do they fit in?

Whatever group you’re talking about, there are some key implications for the pandemic, and trying to rein it in. One: Some percentage of infected people — roughly 20%, according to one recent review, though other studies have produced higher estimates — do not show symptoms at all. And two: Whether or not someone is asymptomatic or presymptomatic, they can still spread the virus (though whether they spread it as efficiently as people with symptoms is still unknown). That is why public health campaigns have been stressing distancing, masks, and hand hygiene for everyone, not just people who feel sick. Once you do start showing symptoms and try to restrict contact with others, it is too late to prevent spread.

Mutations to the virus haven’t been consequential

Coronaviruses in general do not mutate very quickly compared to other viral families. This is a good thing: The leading vaccine candidates, for example, are based on SARS-CoV-2’s genetic sequence, so theoretically a major change in that lineup could hinder the effectiveness of any vaccine. So far, that doesn’t seem to have happened.

Still, scientists have noticed smaller changes in the genome. The one that has gotten the most attention was one swap in the “letters” that make up the virus’ RNA, which created the “G variant.” The switch happened early in the pandemic, and the G variant has since become dominant around the world. Scientists haven’t been able to figure out, however, whether the G variant is outcompeting its predecessor — perhaps it’s more contagious? — or if that’s just chance. And so far, they haven’t landed on evidence that people who contract the G variant get more or less sick than those infected by the other variant. It could just be a mutation that’s like changing your T-shirt from navy blue to royal blue — an aesthetic difference, but something pretty neutral.

Viruses on surfaces probably aren’t the major transmission route

Throughout the spring, you could barely find hand sanitizer. Fears that viruses lurking on surfaces could infect us with Covid-19 turned most of us into zealous surface cleaners. Some people went so far as to quarantine their mail, not touching it for days as they waited for potential lingering viruses to die.

The general consensus now is that “fomites” — germs on surfaces — aren’t the major transmission route for Covid-19. Van Kerkhove of WHO said there hasn’t been a case recorded where it’s clear someone was infected by fomites alone.

(In the real world, someone in close enough contact with an infected person to become infected will likely have encountered viruses on surfaces and virus-laced droplets and maybe even small, aerosol-sized particles containing the virus that have been expelled by coughing, singing, or speaking. Teasing out of that situation which route of transmission triggered infection may be impossible to do.)

But it’s clear from lots of studies that surfaces around infected people can be contaminated with viruses and the viruses can linger. Cleaning surfaces and being prudent about hand hygiene is a risk-lowering step people can take, public health officials agree.

What we don’t know
People seem to be protected from reinfection, but for how long?


The thinking is that a case of Covid-19, like other infections, will confer some immunity against reinfection for some amount of time. But researchers won’t know exactly how long that protection lasts until people start getting Covid-19 again.

So far, despite some anecdotal reports, scientists have not confirmed any repeat Covid-19 cases.

All that supports the notion that Covid-19 acts like other viral infections, including illnesses caused by other coronaviruses. Researchers are finding that most infected people mount an immune response involving both antibodies and immune cells that clears the virus, and that persists for some amount of time. Reports of waning antibody levels incited some concern that perhaps protection to SARS-CoV-2 might not last very long, with big implications for the frequency of required vaccine boosts. But immunologists have pointed out that antibodies for other viruses wane as well; their levels surge upon re-exposure to the pathogen and they can still halt reinfection.

Researchers don’t know for sure what level of antibodies are required to block the virus from gaining a toehold in cells, and what role pathogen-fighting T cells might have in fending off an infection. People who recover from Covid-19 also produce varying levels of antibodies — it’s possible people who generate a weaker initial immune response might not be protected for as long from reinfection.

“We don’t know for how long that immune response lasts,” the WHO’s Van Kerkhove said last week. “We don’t know how strong it is.”

What happens if or when people start having subsequent infections?

Given that most respiratory viruses are not “one-and-done” infections — they don’t induce life-long immunity in the way a virus like measles does — there is a reasonable chance that people could have more than one infection with Covid-19.

Experience with human coronaviruses — which mostly cause colds — supports that idea. A study in the Netherlands followed people for decades, measuring their antibodies to four human coronaviruses at regular intervals and looking for changes that would indicate a new infection. The scientists found that reinfection could occur within a year of the first infection. (The study is a preprint, meaning it hasn’t yet been through the peer review process.)

Some scientists have theorized that on subsequent infections, immune systems might mount quicker responses to Covid-19, leading to milder infections. If that’s true, the SARS-CoV-2 virus might transition into a less daunting threat over time. But it’s still a big unknown. “We don’t know,” Van Kerkhove said. “I don’t want to speculate.”

How much virus does it take to get infected?

Whether you become infected or not when you encounter a pathogen isn’t just a question of whether you’re susceptible or immune. It depends on how much of the virus (or bacterium) you encounter.

And the amount capable of tipping the balance is what’s known as the minimum infectious dose. Some pathogens have a low infectious dose. For example, it doesn’t take a lot of E. coli 0157, a dangerous bacterium transmitted in food, to make someone sick.

How big a dose of SARS-CoV-2 does it take to infect most people? It’s one of the burning questions in SARS-CoV-2 research, said Angela Rasmussen, a coronavirus expert at Columbia University. “We don’t know the amount that is required to cause an infection, but it seems that it’s probably not a really, really small amount, like measles.”

How many people have been infected?

There have been 21 million confirmed cases of Covid-19 around the world, and 5.3 million in the United States. Far more people than that have actually had the virus.

Problems with testing, and its limited availability, have contributed to that gap, as has the fact that some people have such mild or no symptoms that they don’t know they’re infected. But researchers don’t know just how big of a gulf they’re dealing with — how much spread they’ve missed.

“Serosurveys” — which rely on testing for the level of SARS-CoV-2 antibodies in a community — are starting to help fill in some knowledge. A recent CDC study of 10 cities and states estimated that in most places, the true number of infections was some 10 times higher than the number of confirmed cases.

Still, that leaves perhaps 20% of people, even in hard-hit communities, with potential immunity to Covid-19. That means that herd immunity — the point at which so many people are immune that the virus can’t circulate — remains far off even in areas that have suffered severe outbreaks.

It’s not clear why some people get really sick, and some don’t

The sheer range of outcomes for people who get Covid-19 — from a truly asymptomatic case, to mild symptoms, to moderate disease leading to months-long complications, to death — has befuddled infectious disease researchers.

There are some clear factors for who faces higher risks of getting severely ill: older people, as well as people with conditions ranging from cancer to obesity to sickle cell disease.

But scientists have postulated that a host of other underlying factors could help dictate why most healthy 30-year-olds shake off the virus after a couple days and some get severely ill. Researchers are studying genetic differences in patients, while others are looking at blood type.

Recent studies have pointed to another potential player. Perhaps up to half the population has immune-system T cells that were initially generated in response to an infection by one of the common cold-causing coronaviruses but that can recognize SARS-CoV-2 as well. These “cross-reactive” T cells could help give the immune system the boost it needs to stave off serious symptoms, but researchers don’t know for sure what role, if any, they actually play.

Correction: An earlier version of this story misstated the cause of myasthenia gravis, an autoimmune disorder that results in faulty communication between nerves and muscles.

About the Authors

Andrew Joseph
General Assignment Reporter
Andrew is a general assignment reporter.
andrew.joseph@statnews.com
@DrewQJoseph

Helen Branswell
Senior Writer, Infectious Disease
Helen covers issues broadly related to infectious diseases, including outbreaks, preparedness, research, and vaccine development.
@HelenBranswell

Elizabeth Cooney
General Assignment Reporter
Liz is a general assignment reporter.
elizabeth.cooney@statnews.com
@cooney_liz
‘Long-haulers’ don’t feel like they’ve recovered.

I can attest to this. My wife had it linger for a month from her first signs of symptoms back in February in March.

Sent from my Moto Z (2) using Tapatalk
 

RxCowboy

Has no Rx for his orange obsession.
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Ginger Cameron, PhD

Covid-19 Update: Monday, August 24th
Reading level, airplane transmission, Remdesivir, new cases.

1. According to the CDC, COVID information that is shared with the public should be written at an 8th-grade level in order to maximize understanding. However, in an article published in JAMA that assessed COVID information they found most of it was written above the 8th grade level with significant amounts being at the 11th-grade level which is above the average reading level.

2. Current airplane transmission protocols include an assumption that COVID-19 can transmit about 2 rows – but a study conducted from tourists on a flight from Tel Aviv to Frankfort suggests it could spread further than 2 rows when protective measures are not taken (masks, etc.). You can read more about this study in JAMA.

3. In a clinical trial, hospitalized individuals who received Remdesivir as treatment were doing better, clinically than those who received standard care. This is a nice step in the process and indicates Remdesivir may be a viable option for the treatment of hospitalized patients. You can read more in JAMA.

4. New cases yesterday were in the 30k range which is the lowest we have seen in some time. Let’s hope it is part of a downward trend as more and more areas begin to pass mask mandates and social distancing becomes more normative.

FINAL THOUGHTS: Today is the start to a new week, hopefully, you took some time to walk away from all things COVID over the weekend. News is slowing down which is great, things are starting to settle a little as our new normal is finally starting to take hold. You have done well and weathered the storm thus far. Do not grow weary, stay the course. It is easy to let down your guard as things start to stabilize but it is our valiant efforts that have gotten us this far, now is not the time to give up. Just a little bit longer.
 

RxCowboy

Has no Rx for his orange obsession.
A/V Subscriber
Nov 8, 2004
70,450
40,815
1,743
Wishing I was in Stillwater
Ginger Cameron, PhD

COVID-19 Update: Tuesday, August 25
Second Infection, the NFL, South Korea, CDC and airports.

1. The first verified case of someone catching COVID-19 twice has now been documented. A 33-year-old man in Hong Kong had it in March and in August, caught it a second time while traveling. The good news is that the second infection was much milder than the first.

2. The NFL has 77 positive cases across 11 teams. Most teams are not allowing fans in the stadium, but a few will be.

3. South Korea, who had been the poster of success, has now had over 11 straight days of triple-digit daily increases in new cases.

4. The CDC removed the 14-day quarantine for travelers returning from out of the country or from outside their state.

5. Airports are setting up testing cites inside the airport for incoming passengers. LaGuardia and JFK are the first to begin screening people coming in via air.

FINAL THOUGHTS: Sometimes trying to be strong is exhausting. When those days come, do not pretend to be ok. Find your field and let it out. Call a confidant and groan. Reach out for help because you aren’t alone, and this is a bad situation. But it is not the end of our story, and one day the virus will be controlled, and the pandemic will end just as every pandemic before it has ended. It is a marathon for sure, but it will end, and we will come out the other side stronger, and braver, and better. In the meantime, pace yourself. Seek help when you need it and lend help when you have a little to spare.
 

sc5mu93

WeaselMonkey
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Spring, TX
1. According to the CDC, COVID information that is shared with the public should be written at an 8th-grade level in order to maximize understanding. However, in an article published in JAMA that assessed COVID information they found most of it was written above the 8th grade level with significant amounts being at the 11th-grade level which is above the average reading level.
For any document I write, I always run the flesch kincaid reading level test through MS Word on it. Again - 8th grade is what I target. And most of the documents I write are technical in nature. Kind of sad that is the target, but it is what it is.

EDIT: i never even bother with even a spell check on orangepower. you illiterate bastards wouldn't even know the difference. Probably should switch to emoji-speak for this board.
 
May 4, 2011
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Charleston, SC
For any document I write, I always run the flesch kincaid reading level test through MS Word on it. Again - 8th grade is what I target. And most of the documents I write are technical in nature. Kind of sad that is the target, but it is what it is.

EDIT: i never even bother with even a spell check on orangepower. you illiterate bastards wouldn't even know the difference. Probably should switch to emoji-speak for this board.
:thumbup:
 

Duke Silver

Find safe haven in a warm bathtub full of my jazz.
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For any document I write, I always run the flesch kincaid reading level test through MS Word on it. Again - 8th grade is what I target. And most of the documents I write are technical in nature. Kind of sad that is the target, but it is what it is.

EDIT: i never even bother with even a spell check on orangepower. you illiterate bastards wouldn't even know the difference. Probably should switch to emoji-speak for this board.
I have to be at 6th grade level. Good lord I cant even say physician or covid-19 and keep it that low.
 
May 4, 2011
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Ginger Cameron, PhD

COVID-19 Update: Tuesday, August 25
Second Infection, the NFL, South Korea, CDC and airports.

1. The first verified case of someone catching COVID-19 twice has now been documented. A 33-year-old man in Hong Kong had it in March and in August, caught it a second time while traveling. The good news is that the second infection was much milder than the first.

2. The NFL has 77 positive cases across 11 teams. Most teams are not allowing fans in the stadium, but a few will be.

3. South Korea, who had been the poster of success, has now had over 11 straight days of triple-digit daily increases in new cases.

4. The CDC removed the 14-day quarantine for travelers returning from out of the country or from outside their state.

5. Airports are setting up testing cites inside the airport for incoming passengers. LaGuardia and JFK are the first to begin screening people coming in via air.

FINAL THOUGHTS: Sometimes trying to be strong is exhausting. When those days come, do not pretend to be ok. Find your field and let it out. Call a confidant and groan. Reach out for help because you aren’t alone, and this is a bad situation. But it is not the end of our story, and one day the virus will be controlled, and the pandemic will end just as every pandemic before it has ended. It is a marathon for sure, but it will end, and we will come out the other side stronger, and braver, and better. In the meantime, pace yourself. Seek help when you need it and lend help when you have a little to spare.
#1 seems like mostly good news. There were always going to be reinfections at some point, but we'd hope that immune responses happen quicker with milder symptoms with reinfection, like what many think happens with the flu (we're better at fending off whatever strains we got as kids).
 
May 4, 2011
2,025
1,010
743
Charleston, SC
Ginger Cameron, PhD

COVID-19 Update: Tuesday, August 25
Second Infection, the NFL, South Korea, CDC and airports.

1. The first verified case of someone catching COVID-19 twice has now been documented. A 33-year-old man in Hong Kong had it in March and in August, caught it a second time while traveling. The good news is that the second infection was much milder than the first.

2. The NFL has 77 positive cases across 11 teams. Most teams are not allowing fans in the stadium, but a few will be.

3. South Korea, who had been the poster of success, has now had over 11 straight days of triple-digit daily increases in new cases.

4. The CDC removed the 14-day quarantine for travelers returning from out of the country or from outside their state.

5. Airports are setting up testing cites inside the airport for incoming passengers. LaGuardia and JFK are the first to begin screening people coming in via air.

FINAL THOUGHTS: Sometimes trying to be strong is exhausting. When those days come, do not pretend to be ok. Find your field and let it out. Call a confidant and groan. Reach out for help because you aren’t alone, and this is a bad situation. But it is not the end of our story, and one day the virus will be controlled, and the pandemic will end just as every pandemic before it has ended. It is a marathon for sure, but it will end, and we will come out the other side stronger, and braver, and better. In the meantime, pace yourself. Seek help when you need it and lend help when you have a little to spare.
Assuming that posting from statnews doesn't count as sociopolitical discussion but gives a primer on what I was saying about #1 in my other post.

https://www.statnews.com/2020/08/25/four-scenarios-on-how-we-might-develop-immunity-to-covid-19/