Study finds people have short-lived immunity to seasonal coronaviruses(directorsblog.nih.gov)
directorsblog.nih.gov
Study finds people have short-lived immunity to seasonal coronaviruses
https://directorsblog.nih.gov/2020/09/29/study-finds-people-have-short-lived-immunity-to-seasonal-coronaviruses/
67 comments
I am not an epidemiologist (it took me three tries to even spell it correctly), but here's my baseless internet speculation. Maybe seasonal coronaviruses have this short-lived immunity because they've been been exposed to a lot of selective pressure for it. If our bodies produced long-term immunity to a coronavirus, it'd tend to die out, while ones that only induce short-term immunity would tend to survive by re-circulating. So maybe it's sort of obvious that common coronaviruses would have short-term immunity, but that doesn't really tell us much about a random novel coronavirus? Or is that crazy?
I'm not an epidemiologist either, but to this layperson, the viruses studied seem to have been chosen on criteria that select for short-lived immunity. It seems likely that "seasonal" viruses, viruses "that regularly circulate to cause the condition we recognize as the common cold" must induce short-lived immunity.
Would it be possible for a virus that induced long-lived immunity to be seasonal, reoccurring year after year?
And why were the other coronaviruses that infect humans left out of the study?
Would it be possible for a virus that induced long-lived immunity to be seasonal, reoccurring year after year?
And why were the other coronaviruses that infect humans left out of the study?
> And why were the other coronaviruses that infect humans left out of the study
Because one of them, SARS-1 went extinct in just over a year due to a heroic international response, and the other, MERS, has about a 35% fatality rate and is unlikely to be found in anyone who does not have direct contact with camels.
Because one of them, SARS-1 went extinct in just over a year due to a heroic international response, and the other, MERS, has about a 35% fatality rate and is unlikely to be found in anyone who does not have direct contact with camels.
There are a number of problems I have with this report, a presumption(that was false) was that covid-19 was going to follow the seasonality of the common cold and the flu. That prediction turned out to be really incorrect as cases in the US exploded in the summertime when they were expected to wane. This report compares the 4 corona viruses which follow that track to covid-19 which does not. Another article offers some interesting insight on why some get severe cases vs. others that do not, its related to T cells, which the OP's article also ignores. - https://www.bmj.com/content/370/bmj.m3563
> That prediction turned out to be really incorrect as cases in the US exploded in the summertime when they were expected to wane.
Deaths aren't tracking cases, and the tests are probably too sensitive [0], so for all we know it really did wane in the summer. We're in a weird place with this virus in that we don't do anywhere near this extensive testing for other viruses, so we don't actually know if this is normal or not.
[0] https://www.nytimes.com/2020/08/29/health/coronavirus-testin...
Deaths aren't tracking cases, and the tests are probably too sensitive [0], so for all we know it really did wane in the summer. We're in a weird place with this virus in that we don't do anywhere near this extensive testing for other viruses, so we don't actually know if this is normal or not.
[0] https://www.nytimes.com/2020/08/29/health/coronavirus-testin...
> covid-19 was going to follow the seasonality of the common cold and the flu. That prediction turned out to be really incorrect as cases in the US exploded in the summertime when they were expected to wane.
How do you know the virus wasn't waning? I have always anticipated that summer was us giving us a break before it got worse in the Fall and Winter. Perhaps it is seasonal, we won't know until Spring. It may be bad in Summer, but really bad during the other times.
How do you know the virus wasn't waning? I have always anticipated that summer was us giving us a break before it got worse in the Fall and Winter. Perhaps it is seasonal, we won't know until Spring. It may be bad in Summer, but really bad during the other times.
> a presumption(that was false)
We won't know if it's false until we've experienced both summer and winter in both the northern and southern hemispheres.
Yes, cases increased were high in the summer in the US, but that doesn't tell us anything about whether it will be the same, or lower, or higher in the winter.
We won't know if it's false until we've experienced both summer and winter in both the northern and southern hemispheres.
Yes, cases increased were high in the summer in the US, but that doesn't tell us anything about whether it will be the same, or lower, or higher in the winter.
I think you're talking about another kind of seasonality.
The common cold and influenza are seasonal in the sense that most infections occur during some time in the colder months.
The researchers were trying to figure out how long-lived immunity to other coronaviruses is. Their question was not about the severity of cases, but whether a reinfection is possible. They found that in most cases, levels of antibodies against 4 common coronaviruses spiked about a year after the previous infection.
That could either just mean that the patients still had immunity and their immune system was able to quickly produce more antibodies when they came in contact with the virus again.
But it could also indicate a reinfection. In that case, symptoms would be observable.
As symptoms were not recorded, we are unable to tell which case occurred more often.
The common cold and influenza are seasonal in the sense that most infections occur during some time in the colder months.
The researchers were trying to figure out how long-lived immunity to other coronaviruses is. Their question was not about the severity of cases, but whether a reinfection is possible. They found that in most cases, levels of antibodies against 4 common coronaviruses spiked about a year after the previous infection.
That could either just mean that the patients still had immunity and their immune system was able to quickly produce more antibodies when they came in contact with the virus again.
But it could also indicate a reinfection. In that case, symptoms would be observable.
As symptoms were not recorded, we are unable to tell which case occurred more often.
Sorry, if there’s no long lived immunity, there also can’t be a vaccine.
They are hoping the immunity lasts 12 months. Then you would take a booster in your annual flu shot. I could live with that.
That is not necessarily true. It's possible for a vaccine to elicit a stronger or longer lasting immune response than the pathogen itself. For example by adding adjuvants
https://en.m.wikipedia.org/wiki/Immunologic_adjuvant
https://en.m.wikipedia.org/wiki/Immunologic_adjuvant
I don't see where in that article it says what you are describing. Only that adjuvants may improve the response to a vaccine. The response to the pathogen is not considered.
That doesn't sound right. Perhaps there could be a stream of vaccines rather than a one-off.
Also, if you can get enough people vaccinated at one time to provide herd immunity, perhaps it wouldn't be necessary to have long-term immunity, as the pandemic could be ended there and then.
Also, if you can get enough people vaccinated at one time to provide herd immunity, perhaps it wouldn't be necessary to have long-term immunity, as the pandemic could be ended there and then.
[deleted]
I don’t buy it. The comparison should be done between other similar aerial coronaviruses, like the 1919 pandemic flu one. The fact that in that case it vanished by itself it’s a big tell about our herd and personal immunities.
Since this kind of distracting articles is very common, I wonder if there is behind those a willingness to scare people...
Personal opinions
Just FYI Influenza is not a coronavirus. They can both be grouped (along with many other diseases) under the term ARI (Airborne Respitory Infection).
It's so important to be precise and specific when taking about Covid19; it's not flu.
The 1919 pandemic didn't just "disappear" it killed many of its hosts, and people used social distancing, additional hygiene measures, and mask wearing to help reduce the infection rates. AIUI it was more rapid in producing symptoms and more deadly - leading to less infections and perhaps less deaths than a Covid19-like virus might (at that point in history).
It's so important to be precise and specific when taking about Covid19; it's not flu.
The 1919 pandemic didn't just "disappear" it killed many of its hosts, and people used social distancing, additional hygiene measures, and mask wearing to help reduce the infection rates. AIUI it was more rapid in producing symptoms and more deadly - leading to less infections and perhaps less deaths than a Covid19-like virus might (at that point in history).
Also travel outside your town (or even your part of town) was a lot less frequent then. People lived a lot closer to where they worked and shopped and socialized.
Cars were around, but nearly as common as they are now. In 1919 there were 72.5 cars per 1000 people in the US. It was 838 in 2018.
Cars were around, but nearly as common as they are now. In 1919 there were 72.5 cars per 1000 people in the US. It was 838 in 2018.
We keep on hearing that having the antibodies = no resistance to subsequent infection and then articles like this. I also don't buy it fully.
Antibodies are tied into what helped you get over your initial infection, if they don't do anything how did you clear initial infection? Sure - we don't have the studies yet - but this claim that there is no immunity is totally bogus - the reality - we don't yet have a study for THIS virus to show the full cycle of immunity - that doesn't mean Covid is a magic virus.
Secondly, this title "short lived immunity" is ridiculous. The issue is immune response, ie, when re-infected can your body clear disease efficiently. Isn't that how most immune responses work, you don't even really trigger them pre-infection. But then you get an exposure, body response kicks in (often better on repeat) etc.
I'm tired of these "masks don't help", "antibodies mean nothing", "reinfections are common" type articles.
Antibodies are tied into what helped you get over your initial infection, if they don't do anything how did you clear initial infection? Sure - we don't have the studies yet - but this claim that there is no immunity is totally bogus - the reality - we don't yet have a study for THIS virus to show the full cycle of immunity - that doesn't mean Covid is a magic virus.
Secondly, this title "short lived immunity" is ridiculous. The issue is immune response, ie, when re-infected can your body clear disease efficiently. Isn't that how most immune responses work, you don't even really trigger them pre-infection. But then you get an exposure, body response kicks in (often better on repeat) etc.
I'm tired of these "masks don't help", "antibodies mean nothing", "reinfections are common" type articles.
> We keep on hearing that having the antibodies = no resistance to subsequent infection and then articles like this. I also don't buy it fully.
> Antibodies are tied into what helped you get over your initial infection, if they don't do anything how did you clear initial infection?
It's not magic, it really is a thing with mutations in a handful of other viruses: https://en.m.wikipedia.org/wiki/Antibody-dependent_enhanceme...
It was an early fear that I think we're past by now.
> Antibodies are tied into what helped you get over your initial infection, if they don't do anything how did you clear initial infection?
It's not magic, it really is a thing with mutations in a handful of other viruses: https://en.m.wikipedia.org/wiki/Antibody-dependent_enhanceme...
It was an early fear that I think we're past by now.
It would be better if the just admitted they don't have a clue, and masks look like they make sense. Lockdowns seemed to make sense, until Sweden showed that they probably were not necessary. I would respect them more for that.
It's important to look at Sweden's culture and what they did do. They gave recommendations and did do a partial shutdown, and much of their populace actually listen to the government recommendations, unlike the American populace.
It's also important to compare cities and countries of comparable magnitude, size can make a big difference.
It's also important to compare cities and countries of comparable magnitude, size can make a big difference.
> much of their populace actually listen to the government recommendations, unlike the American populace
Americas have followed the rules, in almost all regions. People all over the US stopped being social days or weeks before the lockdowns even started.
What are you basing this on?
Americas have followed the rules, in almost all regions. People all over the US stopped being social days or weeks before the lockdowns even started.
What are you basing this on?
Not in major areas such as Los Angeles, San Diego and other hot spots. Both from friends I've talked to in the area, to video footage, to instagrams to media. This is also true of many republican cities and states through Texas, Florida and the South.
Many stopped immediately, but many have no stopped. There are even COVID parties, and open rallies with 500,000 attendies: https://www.forbes.com/sites/tommybeer/2020/09/08/sturgis-mo...
Many stopped immediately, but many have no stopped. There are even COVID parties, and open rallies with 500,000 attendies: https://www.forbes.com/sites/tommybeer/2020/09/08/sturgis-mo...
A flu pandmenic was probably cause by an influenza virus, hence the name.
The 1919 flu pandemic was caused by an influenza virus, not a coronavirus. They're not all that similar. In the Linnaean classification, they don't even belong to the same phylum.
... but those don't have the spike protein that CoVID has.
>... but those don't have the spike protein that CoVID has.
What does that mean? Do they not have similarly unique antigens?
What does that mean? Do they not have similarly unique antigens?
A virus needs only a handful of genes/proteins to work, one of them is a "virulence" factor that binds to a receptor on the cell which starts the cell entry and infection process.
CoVID-19 is a much more dangerous disease than other coronaviruses because it has a spike protein that binds to the ACE-2 receptor on your kidney, heart, blood vessel, and yes lung cells. Other coronaviruses have different spike proteins that bind to different receptors and don't seem to kill people effectively as the CoVID-19 spike protein.
CoVID neutralizing antibodies target the unique spike protein so the fact that other coronaviruses don't present a durable target isn't relevant.
CoVID-19 is a much more dangerous disease than other coronaviruses because it has a spike protein that binds to the ACE-2 receptor on your kidney, heart, blood vessel, and yes lung cells. Other coronaviruses have different spike proteins that bind to different receptors and don't seem to kill people effectively as the CoVID-19 spike protein.
CoVID neutralizing antibodies target the unique spike protein so the fact that other coronaviruses don't present a durable target isn't relevant.
Yea, but if you include that information than you can't make a click bait headline that spreads fear
Doesn't it make it worse, from a fear perspective?
The spike protein makes it for virulent, but is also a "feature" that the immune response can attack. Double-edged sword really.
Important notes: No data is available on actual illness according to the article, which means that while there could be an immune response, that does not mean that symptoms were observed. This study also does not regard the impact of T-cells, which were determined to mediate the immune response to COVID [1]. The paper acknowledges this shortcoming.
[1] https://www.nature.com/articles/s41577-020-00436-4
[1] https://www.nature.com/articles/s41577-020-00436-4
It's important to distinguish between sterilizing immunity and protective immunity here. It's pretty common to get re-infected relatively quickly by a Coronavirus but previous studies showing the same thing also showed that these re-infections didn't cause disease, that is symptoms. And since transmissibility is generally correlated with intensity of symptoms there's reason to believe that vaccination still helps with that, though not as much as we would hope.
And our few examples of known re-infections with SARS-2 don't seem to have caused disease the second time around.
And our few examples of known re-infections with SARS-2 don't seem to have caused disease the second time around.
> And since transmissibility is generally correlated with intensity of symptoms
Is asymptomatic and pre-symptomatic transmission no longer thought of as a significant transmission route anymore?
Is asymptomatic and pre-symptomatic transmission no longer thought of as a significant transmission route anymore?
Sorry, correlated with the maximum intensity of symptoms over the course of the disease. Your viral load peaks right before you develop symptoms (generally). But viral load at peak tends to predict the severity of later symptoms and so being long-term asymptomatic is correlated with lower peak viral load. Plus, in addition to viral load, some symptoms like coughing increase transmissibility.
EDIT: I'm not saying that a vaccine that conveys protective but not sterilizing immunity means we can stop worrying about true asymptomatic transmission entirely. But I'd assume that it's enough to driver the natural R0 well below 1.0 if everyone gets the vaccine all by itself.
EDIT: I'm not saying that a vaccine that conveys protective but not sterilizing immunity means we can stop worrying about true asymptomatic transmission entirely. But I'd assume that it's enough to driver the natural R0 well below 1.0 if everyone gets the vaccine all by itself.
With COVID-19 there are 2 confirmed cases of reinfection. 1 of them did not have symptoms on reinfection but the other did.
Out of tens of millions of cases, we have had 2 reinfections, one of whom had symptoms. To me that is very very strong evidence that reinfection is not a factor.
I know it’s likely the vaccines are actually going to help against Covid, and I really hope the experts are right, but I can’t shake the feeling that this new world is simply the new normal.
So far, expecting things to turn out semi-shitty seems to be the way to go. At first our national health agency didn’t take the threat seriously. Then they took it very seriously but didn’t think we’d see a second wave because our restrictions worked. Heh, now we’re heading toward a winter with high amounts of new restrictions that are targeted at the second wave that is unlikely to lift until sometime next year. And this is in a country that has so far handled the pandemic better than most.
So far, expecting things to turn out semi-shitty seems to be the way to go. At first our national health agency didn’t take the threat seriously. Then they took it very seriously but didn’t think we’d see a second wave because our restrictions worked. Heh, now we’re heading toward a winter with high amounts of new restrictions that are targeted at the second wave that is unlikely to lift until sometime next year. And this is in a country that has so far handled the pandemic better than most.
> new restrictions that are targeted at the second wave that is unlikely to lift until sometime next year
The actual number of fatalities are dropping in almost every region. The trouble with "new cases" is they just add to the existing insanely high number, instead of resetting to cases-per-month. A lot of these cases aren't even serious at all. Remember during the H1N1 flu, Obama actually reduced testing to quell fear.
And the restrictions are likely going away. It's been months and humanity cannot go on this way. Ecuador high courts have struck down a lot of their lockdown restrictions and emergency powers. In the US, the Stickman decision in PA could be the most important decision of this entire year[0]. We're seeing lockdown protest in Germany, UK and there would be protests in Australia if Victoria didn't go absolutely insane.
I realize a lot of people have died, but in the US, 96% of them are over 55. The "long term effects" narrative is taking hold, and I've read the UK case study of 60+ patients published through a Charlottesville journal, and the majority of them were elderly or high risk.
https://battlepenguin.com/politics/secondary-effects/
Only 6k people in the US died without having an additional comorbidity (heart disease, obesity, etc.)
It's time to isolate the vulnerable, and let the rest of the population go back to making their own decisions about what risks they want to take with their lives. Offer subsidies for people who want groceries delivered and never want to go out and take any risks again.
100 year from now, historians will look back at 2020 as the year of mass hysteria.
[0]: https://www.youtube.com/watch?v=InCIyID5rkE
The actual number of fatalities are dropping in almost every region. The trouble with "new cases" is they just add to the existing insanely high number, instead of resetting to cases-per-month. A lot of these cases aren't even serious at all. Remember during the H1N1 flu, Obama actually reduced testing to quell fear.
And the restrictions are likely going away. It's been months and humanity cannot go on this way. Ecuador high courts have struck down a lot of their lockdown restrictions and emergency powers. In the US, the Stickman decision in PA could be the most important decision of this entire year[0]. We're seeing lockdown protest in Germany, UK and there would be protests in Australia if Victoria didn't go absolutely insane.
I realize a lot of people have died, but in the US, 96% of them are over 55. The "long term effects" narrative is taking hold, and I've read the UK case study of 60+ patients published through a Charlottesville journal, and the majority of them were elderly or high risk.
https://battlepenguin.com/politics/secondary-effects/
Only 6k people in the US died without having an additional comorbidity (heart disease, obesity, etc.)
It's time to isolate the vulnerable, and let the rest of the population go back to making their own decisions about what risks they want to take with their lives. Offer subsidies for people who want groceries delivered and never want to go out and take any risks again.
100 year from now, historians will look back at 2020 as the year of mass hysteria.
[0]: https://www.youtube.com/watch?v=InCIyID5rkE
Maybe for a year or so but people will just forget about it and move on.
Kinda like smoking which kills 500k americans every year.
Kinda like smoking which kills 500k americans every year.
All normative opinions aside, this cannot become a new normal. People will not tolerate it. The majority of the population will not continue to remain cloistered in a small area due to the vulnerability of a minority. It's also economically untenable. So no, I don't think it will. We may, however, see significantly more deaths from those at risk, or they may be stuck entirely holed-up as a result.
jdavis703(2)
The alarming thing about the justification of these measures is that it seems it can never be invalidated.
Covid is endemic (it is not a pandemic). When exactly will we experience no mass covid deaths? (we experience mass flu deaths).
Simply, never. Is it really that in 3yr time we will be "happy" with a 0.2% rate? (ie., 50% of current rate). Will "half the number of grandparents" dying be a tolerable amount?
The justification behind everything here is alarmingly short-termism, I can only imagine govs are waiting for some kind of "vaccine" or "health theatre" that will allow people to resume normal behaviour. (cf. airport security theatre exists to encourage people to fly; it is demanded by airlines so people feel flying is safe. One assumes they hope vaccines will play the same role.)
However gov.s are at their financial breaking points re Lockdown as a strategy, and it'll be this that goes first. Hard to say what the political ramifications of that are, many middle-class shut-ins simply refuse to believe gov. is a limited actor.
Covid is endemic (it is not a pandemic). When exactly will we experience no mass covid deaths? (we experience mass flu deaths).
Simply, never. Is it really that in 3yr time we will be "happy" with a 0.2% rate? (ie., 50% of current rate). Will "half the number of grandparents" dying be a tolerable amount?
The justification behind everything here is alarmingly short-termism, I can only imagine govs are waiting for some kind of "vaccine" or "health theatre" that will allow people to resume normal behaviour. (cf. airport security theatre exists to encourage people to fly; it is demanded by airlines so people feel flying is safe. One assumes they hope vaccines will play the same role.)
However gov.s are at their financial breaking points re Lockdown as a strategy, and it'll be this that goes first. Hard to say what the political ramifications of that are, many middle-class shut-ins simply refuse to believe gov. is a limited actor.
The relationship between Covid-19 and other seasonal coronaviruses is unclear at best. In particular, this study is contradicted by evidence of long-lasting immunity for SARS-Cov-1 survivors. So far, evidence of reinfection with Covid-19 seems limited to a handful of people. However, if reinfection becomes more prevalent (say next year), then we're really up a creek without a paddle. At that point, the only viable strategies left will be global eradication, or repeat vaccination akin to the seasonal flu.
As a layman: How is immunity defined?
The German virologist Drosten said in an interview (a while ago, sorry, no source) that it is expected that survivors will stop producing white blood cells at some point. The next time they get infected with COVID-19 they will develop symptoms of a common cold and get rid of the virus much quicker.
The German virologist Drosten said in an interview (a while ago, sorry, no source) that it is expected that survivors will stop producing white blood cells at some point. The next time they get infected with COVID-19 they will develop symptoms of a common cold and get rid of the virus much quicker.
Immunity is complex. Every article tries to reduce it to antibodies, but antibodies are just one aspect of "memory."
Our immune systems have an inane immune system, an adaptive immune system, a Complement Protein system[0], with hundreds of thousands of proteins that have evolved over millions of years to change shape and form to grab onto and destroy all kinds of bacteria and viruses in the most random/crazy ways possible (It's a lot like microservices, except random monkeys throwing code at a wall and eventually making things work over millions of years), and many many other pieces.
Every vaccine we have today is either based off an inactivated virus or an attenuated virus (a virus moved though hosts to be less lethal to humans). The first vaccine used HorsePox/CowPox to create immune memory for SmallPox by Jenner, 185 years ago.
A lot of these newer vaccines like mNRA vaccines, are not vaccines at all. They attempt to generate antibodies specifically. But there could be hundreds of other interactions that occur when a virus enters your system, that can help build immunity. There's a lot we simply do not know about.
Attempts at SARS1/MERS vaccines led to Imunopathic responses and Immune Enhancement Syndrome. Vaccines are some carefully engineered, invention of science. They came about due to horrific diseases, where doctors tested and experimented on human beings because thousands were going blind, getting paralyzed or dying.
The rush to create a vaccine, with methods that have never successfully created a vaccine before, should be of great concern to everyone.
[0]: https://www.youtube.com/watch?v=BSypUV6QUNw
Our immune systems have an inane immune system, an adaptive immune system, a Complement Protein system[0], with hundreds of thousands of proteins that have evolved over millions of years to change shape and form to grab onto and destroy all kinds of bacteria and viruses in the most random/crazy ways possible (It's a lot like microservices, except random monkeys throwing code at a wall and eventually making things work over millions of years), and many many other pieces.
Every vaccine we have today is either based off an inactivated virus or an attenuated virus (a virus moved though hosts to be less lethal to humans). The first vaccine used HorsePox/CowPox to create immune memory for SmallPox by Jenner, 185 years ago.
A lot of these newer vaccines like mNRA vaccines, are not vaccines at all. They attempt to generate antibodies specifically. But there could be hundreds of other interactions that occur when a virus enters your system, that can help build immunity. There's a lot we simply do not know about.
Attempts at SARS1/MERS vaccines led to Imunopathic responses and Immune Enhancement Syndrome. Vaccines are some carefully engineered, invention of science. They came about due to horrific diseases, where doctors tested and experimented on human beings because thousands were going blind, getting paralyzed or dying.
The rush to create a vaccine, with methods that have never successfully created a vaccine before, should be of great concern to everyone.
[0]: https://www.youtube.com/watch?v=BSypUV6QUNw
One of the known reinfections got it worse the second time, see the thread here: https://twitter.com/virusesimmunity/status/12993422701777264...
25 year old patient, sequenced genomes of virus differed significantly. Looks like a real re-infection.
Could you clarify: are you saying "long-lasting immunity for SARS-Cov-1 survivors" against SARS, or immunity against Covid19? I assume the former, but it's ambiguous to me, sorry.
Largely the first but also a smattering of the second (in the form of less serious cases in people previously exposed to SARS-COV-1), from the one (iirc) study that looked into this.
> So far, evidence of reinfection with Covid-19 seems limited to a handful of people.
Is there even enough evidence in those few cases that it was really a reinfection? RT-PCR based tests are good but are not perfect after all, false positives happen.
Is there even enough evidence in those few cases that it was really a reinfection? RT-PCR based tests are good but are not perfect after all, false positives happen.
And also, no one is reporting the number of test iterations that are being used for each positive result. There are people with very low viral loads, who are not contagious, that test positive.
If you run a RT-PCT enough times, you can generate a match in many cases where someone has never had the virus. The inventor of the PCR (who passed away years ago) took great issue with the way PCR was being using incorrectly with HIV testing. Even today with HIV, PCR is often reported with a viral load number, so doctors can tell what amount of antiviral drugs are needed for patients, and to help identify long-term non-progressives (rare) who may not need drugs at all.
If you run a RT-PCT enough times, you can generate a match in many cases where someone has never had the virus. The inventor of the PCR (who passed away years ago) took great issue with the way PCR was being using incorrectly with HIV testing. Even today with HIV, PCR is often reported with a viral load number, so doctors can tell what amount of antiviral drugs are needed for patients, and to help identify long-term non-progressives (rare) who may not need drugs at all.
There is this person who had two genetically different COVID-19 strains (but presumably the same serotype, there's only one serotype of COVID-19 known) for the first and second infection, confirmed by whole genome sequencing: https://doi.org/10.1093/cid/ciaa1275
No shit. I guess that’s why I get a cold every winter.
Colds aren’t really seasonal, and while some may be caused by coronaviruses, the more common infections are caused by the rhinovirus. Did you mean the flu?
Not to mention all the others: https://en.wikipedia.org/wiki/Common_cold#Viruses