Antibody levels highly predictive of immune protection from symptomatic Covid
nature.com
nature.com
> The estimated neutralization level for protection from severe infection is approximately sixfold lower than the level required to protect from any symptomatic infection. Thus, a higher level of protection against severe infection is expected for any given level of vaccine efficacy against mild SARS-CoV-2 infection. Assuming that this relationship remains constant over time, it appears probable that immunity to severe infection may be much more durable than overall immunity to any infection. Long-term studies of antibody responses to vaccinia, measles, mumps or rubella suggest that these responses generally stabilize with half-lives of >10 years. We therefore projected beyond the reported decay of SARS-CoV-2 responses (out to 8 months after infection5), assuming that after 8 months following the infection the decay rate will slow down. We modeled the decay rate of the neutralization titer, assuming that it slowed linearly to a 10-year half-life over 1, 1.5 or 2 years (details in Methods). This analysis predicts that even without immune boosting, a significant proportion of individuals may maintain long-term protection from severe infection by an antigenically similar strain, even though they may become susceptible to mild infection (Fig. 3b,c).
Sounds like good news. This study appears to be saying that the vaccines do a 6x better job of preventing severe covid infection than the known 94% efficacy preventing even mild symptoms from appearing, and that long term immunity [0] might be expected to last decades, similar to other vaccines.
[0], EDIT: "long term protection against severe sickness", as opposed to "immunity", as pointed out by PeterHolzwarth in comment below
https://www.sciencedaily.com/releases/2021/05/210517105727.h...
Here, one of the people associated with the paper mentions:
"Vaccination works very well to prevent both symptoms and severe disease in the short to medium term, but efficacy is predicted to decline over the first few months for most of these vaccines,"
"However, it is very important to understand the difference between immunity against infection and protection from developing severe disease. Our study found that a 6-fold lower level of antibodies is required to protect against severe disease. So even though our analysis predicts that we will start losing immunity to mild infection in the first year after vaccination, protection from severe infection should be longer lived," says Dr Khoury.
Key is that distinction between immunity and protection against severe sickness.
I perceive the topic as characterized by answers to the questions of:
1. How easily can I catch the virus?
2. How likely am I to experience severe symptoms when infected?
3. Are there treatments that will significantly help me if I experience severe symptoms?
My readings indicate covid appears to be more infectious than influenza, but I do not know the comparison between the common cold viruses and covid on this front.
I am uncertain if covid is more or less likely to cause severe symptoms vs influenza. I believe, however, that the viruses that represent the common cold (rhinoviruses) can be definitely characterized as being much more benign in regards to symptoms.
I feel a key issue is #3 - there are few known compounds that can reliably aid in treatment of someone who is experiencing severe symptoms for covid. This is an area of rapidly expanding research now, of course.
There are at least four endemic cold-coronaviruses, plus the adenovirus family, plus a bunch more. The severity of most of these respiratory infections depend a lot on patient comorbidities, and immune history.
The question is: will the virus become endemic. The simple answer is "yes", because it is already endemic: it has multiple mammalian reservoirs, is found in every country on earth, and is ubiquitous in the human population. It is endemic.
Theories about severity, treatment, etc., are completely irrelevant.
Will the virus become endemic and be a common illness? Yes.
Focusing on the "common cold" is a way of making the question about severity, which is clearly not the intent.
A "severe" disease can indeed be endemic, and the "common cold" actually kills a substantial number of people every year. They're completely orthogonal concepts.
This was a super weird reaction to someone's detailed yet brief and thoughtful response.
*not sure if these are the exact number I remember from the lecture.
Type C can infect humans but is typically mild and has not yet caused a serious epidemic.
Type D is not known to infect humans at all.
Now the virus has become endemic, there is much less reason to get vaccinated. For the low-risk and healthy.
He'll have a test against the viruses themselves next week, but he'll need to wait 2 weeks for the result for that test.
Anyways that's why there are specific, slower test that can test his protection against specific virus mutations.
tia
The "95% protection rate" doesn't really mean people don't get infected. Vaccinated people get in contact with as much virus as others.
What it means is their immune system defeats 95% of the infections before you notice you're sick.
But if you get a test while your body is in the middle of crushing such a small infection, you'll test positive.
2. Vaccines don't prevent infection, they reduce severity by training the body's immune system. Natural exposure works the same way. This it is not surprising that 8/9 Yankees which tested positive were asymptomatic
https://www.cdc.gov/media/releases/2021/p0329-COVID-19-Vacci....
> while this study evaluated vaccine effectiveness against infection, including infections that did not result in symptoms.
and also:
> The study demonstrates that these two mRNA vaccines can reduce the risk of all SARS-CoV-2 infections, not just symptomatic infections.
You'll note that this implies a somewhat different definition of "infection" than the one I think you're reaching for.
> Vaccines don't prevent infection, they reduce severity by training the body's immune system
You said:
> I don't know where this misinformation came from, but it is absolutely false. COVID vaccines have been shown to prevent infection...
and cited a link which stated that
> "... two mRNA vaccines can reduce the risk of all SARS-CoV-2 infections, not just symptomatic infections."
So, the vaccines reduce the risk of being the virus being present, as well as the risk that the virus being present will cause symptoms (and by implications, the risk of severe symptoms).
Your link uses the term "infection" to cover both:
* virus present, no symptoms
* virus present, symptoms present
So in that sense, GP is correct: the vaccine does not necessarily prevent the vaccine from being present in the body, but it is effective at reducing the risk that this will cause symptoms.
Of course, your link also implies that there a reduction in the risk that detectable virus will occur after exposure to the virus (which is great!). But my reading of the whole document suggested that the authors are keen to allow for the possibility that a fully vaccinated person may still have detectable viral load in their body. Ergo, it does not "prevent infection".
This entire argument feels pedantic and is based on the idea that the researchers are just playing fast and loose with words.
"The word infection can denote any presence of a particular pathogen at all (no matter how little) but also is often used in a sense implying a clinically apparent infection (in other words, a case of infectious disease).This fact occasionally creates some ambiguity or prompts some usage discussion; to get around this it is common for health professionals to speak of colonization (rather than infection) when they mean that some of the pathogens are present but that no clinically apparent infection (no disease) is present. "
The Yankees are reported to be using the J&J vaccine, which is a viral vector product.
I know this research is still in early stages and the initial sample size was relatively small. And T-cell responses were not measured. There's a decent chance the situation isn't as bad as it initially seems. But it's still discouraging.
[1] Antibody Response to 2-Dose SARS-CoV-2 mRNA Vaccine Series in Solid Organ Transplant Recipients
For one, there are people all around the world waiting for vaccines. If the antibody levels can be used as a general stand in for immunity, there are people that need the vaccines more than those who have the requisite antibodies.
Secondly, intentionally triggering an immune response isn't exactly good for you. The assumption is that a vaccine arrives at an immune response in a less harmful way than getting the infection itself...but for those who have had the infection (and demonstrated a sufficiently high antibody count), retriggering an immune response is subjecting a person to a needless secondary immune response.
The I in HIV and the ID in the name of the associated disease mean something important here.
It also has something to do with what A means in ADE. To make long story short next questions you should ask are:
* what antibody classification systems exists, which one is used and why?
* what's the difference between non-cyclic (natural smallpox, plague, measles) and cyclic (HIV, T-cell leukemia, serum hepatitis, herpes)?
* what does ID have to do with the IFNγR1 gene?
I wouldn't be surprised if we start seeing ADE among vaccinated individuals - there's a good chance their antibodies will be non neutralizing when challenged with live virus a year from now.
Also, it appears governments are motivated to hide information about the vaccine. It's come out the CDC is performing PCR testing for vaccinated individuals with a lower cycle count than for the unvaccinated. There's no reason to trust anything coming out of the CDC with regards to vaccination.
Do you have anything to back up this conspiracy theory? I'm also wondering how many of the ~1 million tests per day are being performed by the CDC itself?
On your second point, this is a recommendation for all tests, nor just the ones performed by the CDC (do they test themselves?)
[1] https://www.cdc.gov/vaccines/covid-19/downloads/Information-...
There's a big scare every time there's a new variant, followed by another article a couple weeks later about how the vaccine is X > 50% effective against [ new variant ].
And the vaccines target spike because there were concerns about ADE with vaccines against the SARS-CoV-1 nucleocapsid protein, but not spike.
Pfizer stimulates both CD4+ and CD8+ T-cells responses:
https://www.fiercebiotech.com/biotech/pfizer-reports-strong-...
https://www.medrxiv.org/content/10.1101/2020.07.17.20140533v...
And the stuff in there about IL-4 and IL-5 and "the absence of a potentially deleterious TH2 immune response" is all about "no signs of ADE".
Natural immunity robust and long lasting: https://www.nytimes.com/2020/11/17/health/coronavirus-immuni...
Killer t cell importance: https://www.nature.com/articles/d41586-021-00367-7
It's hard to find a source now but these PCR tests were being run with cycle counts anywhere from 30-40; in this regime you are extremely likely to amplify noise and generate a huge percentage of false positives. The inventor of the PCR tests made similar comments regarding abuse of the PCR process during the HIV/aids pandemic - and wouldn't you know it, Dr. Fauci was involved in [mis]managing that pandemic as well. His self serving publication and premature press release created an ultimately unfounded stigma around HIV positivity. There is simply no reason to trust the guy now, regardless of his overtly warm, anti-trump persona. And now he has repeatedly denied before congress that he was affiliated with funding/conducting gain of function research on bat coronaviruses. But the publications, with authors publicly and directly linked to Fauci and funds he managed, are freely available online. This should be a far bigger story.