Evidence that we might lose immunity within 2-3 months

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Gordo14
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9:01a, 6/19/20
https://www.cnbc.com/2020/06/18/coronavirus-antibodies-may-last-only-2-to-3-months-after-infection-study-suggests.html

This combined with only 6% of Sweden showing neutralizing antibodies does not bode well for the herd immunity solution. If (and I am by no means stating that this is science yet) we only have immunity for 2-3 months, letting the virus spread uncontrollably is a really dangerous strategy that I don't want to even get into the potential long term implications on. This is another reason why it is critical that we manage the spread of the virus in hopes of a vaccine in 7 months. Ignoring the virus is playing with fire - particularly in November-March.
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abram97
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9:04a, 6/19/20
AG
This is probably crap info - too early to tell. TRUST NOBODY!!!
No material on this site is intended to be a substitute for professional medical advice, diagnosis or treatment. See full Medical Disclaimer.
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Observer
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9:09a, 6/19/20
AG
If antibodies are only good for 2-3 months, then one has to be vacinated every 2-3 months?
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swc93
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9:09a, 6/19/20
AG
Too much info and speculation really hurts the 'PR' for corona-virus and makes it even harder to convince the silent majority to take it seriously. While I appreciate ways scientist and doctors share new findings and fears; I know it just adds fuel to the whole fraud virus crowd. Downfall of sharing information I guess.

With the chance of the long term medical problems that can come along with this virus it would be devastating if some poor souls ending up catching it basically ever quarter.
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Duncan Idaho
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In reply to Gordo14 • 9:09a, 6/19/20
Gordo14 said:
https://www.cnbc.com/2020/06/18/coronavirus-antibodies-may-last-only-2-to-3-months-after-infection-study-suggests.html

This combined with only 6% of Sweden showing neutralizing antibodies does not bode well for the herd immunity solution. If (and I am by no means stating that this is science yet) we only have immunity for 2-3 months, letting the virus spread uncontrollably is a really dangerous strategy that I don't want to even get into the potential long term implications on. This is another reason why it is critical that we manage the spread of the virus in hopes of a vaccine in 7 months. Ignoring the virus is playing with fire - particularly in November-March.


Nature herd immunity is an OUTCOME. It is NOT a solution.

Saying it is a solution is like saying drowning was the solution to the number of life boats on the titanic.
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Gordo14
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In reply to abram97 • 9:11a, 6/19/20
abram97 said:
This is probably crap info - too early to tell. TRUST NOBODY!!!


Not sure what you're point is. It may or may not be accurate. But that fact that we don't know and have data suggesting this published in a reputable journal should be carefully evaluated before we get brash and overconfident. It's a small sample size, but we really have no evidence of long term immunity.
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Jmiller
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9:12a, 6/19/20
Here is a link to the study. https://www.nature.com/articles/s41591-020-0965-6
Quote:
Abstract

The clinical features and immune responses of asymptomatic individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been well described. We studied 37 asymptomatic individuals in the Wanzhou District who were diagnosed with RTPCR-confirmed SARS-CoV-2 infections but without any relevant clinical symptoms in the preceding 14 d and during hospitalization. Asymptomatic individuals were admitted to the government-designated Wanzhou People's Hospital for centralized isolation in accordance with policy. The median duration of viral shedding in the asymptomatic group was 19 d (interquartile range (IQR), 1526 d). The asymptomatic group had a significantly longer duration of viral shedding than the symptomatic group (log-rank P = 0.028). The virus-specific IgG levels in the asymptomatic group (median S/CO, 3.4; IQR, 1.610.7) were significantly lower (P = 0.005) relative to the symptomatic group (median S/CO, 20.5; IQR, 5.838.2) in the acute phase. Of asymptomatic individuals, 93.3% (28/30) and 81.1% (30/37) had reduction in IgG and neutralizing antibody levels, respectively, during the early convalescent phase, as compared to 96.8% (30/31) and 62.2% (23/37) of symptomatic patients. Forty percent of asymptomatic individuals became seronegative and 12.9% of the symptomatic group became negative for IgG in the early convalescent phase. In addition, asymptomatic individuals exhibited lower levels of 18 pro- and anti-inflammatory cytokines. These data suggest that asymptomatic individuals had a weaker immune response to SARS-CoV-2 infection. The reduction in IgG and neutralizing antibody levels in the early convalescent phase might have implications for immunity strategy and serological surveys.

Quote:
In this study, we observed that IgG levels and neutralizing antibodies in a high proportion of individuals who recovered from SARS-CoV-2 infection start to decrease within 2-3 months after infection. In another analysis of the dynamics of neutralizing antibody titers in eight convalescent patients with COVID-19, four patients showed decreased neutralizing antibodies approximately 6-7 weeks after illness onset. One mathematical model also suggests a short duration of immunity after SARS-CoV-2 infection. Together, these data might indicate the risks of using COVID-19 'immunity passports' and support the prolongation of public health interventions, including social distancing, hygiene, isolation of high-risk groups and widespread testing. Additional longitudinal serological studies profiling more symptomatic and asymptomatic individuals are urgently needed to determine the duration of antibody-mediated immunity. In addition, low levels of anti-viral IgG in asymptomatic patients, who might be more likely to become seronegative, further support the need for timely serosurvey to study the true infection rate.

An earlier study that had a similar conclusion.
Apr. 29 2020
[url=https://www.publichealth.columbia.edu/public-health-now/news/risk-coronavirus-reinfection-remains-after-recovery][/url]https://www.publichealth.columbia.edu/public-health-now/news/risk-coronavirus-reinfection-remains-after-recovery
Quote:
Quote:
New research by Columbia University Mailman School of Public Health experts finds that reinfections with endemic coronaviruses are not uncommon, even within a year of prior infection. The study on the four endemic coronavirusesnot including SARS-CoV-2, the virus that causes COVID-19 found that when reinfection occurred, it was not associated with less severe symptoms. Instead, genetic factors may be a greater determinant of the severity of an infection. Individuals who were asymptomatic during their first infection did not experience symptoms during subsequent infections, and members of the same family reported similar symptom severity.
[url=http://www.columbia.edu/~jls106/galanti_shaman_ms_supp.pdf][/url]http://www.columbia.edu/~jls106/galanti_shaman_ms_supp.pdf
Quote:
Quote:
Findings
During the study, 12 individuals tested positive multiple times for the same coronavirus. We found no significant difference between the probability of testing positive at least once and the probability of a recurrence for the beta-coronaviruses HKU1 and OC43 at 34 weeks after enrollment/first infection. We also found no significant association between repeat infections and symptom severity but strong association between symptom severity and belonging to the same family.

Interpretation
This study provides evidence that re-infections with the same endemic coronavirus are not
atypical in a time window shorter than 1 year and that the genetic basis of innate immune response may be a greater determinant of infection severity than immune memory acquired after a previous infection.
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Duncan Idaho
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9:12a, 6/19/20
This has been discussed on here and the article I read this morning mentions the caveat. If true, the durability of immunity is most likely related to the severity of the infection.
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Gordo14
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In reply to Observer • 9:12a, 6/19/20
Observer said:
If antibodies are only good for 2-3 months, then one has to be vacinated every 2-3 months?


Nobody knows. The point is we shouldn't be overconfident and pretend that the issue will solve itself. The virus isn't going away at this point. Let's do our best to manage it.
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amercer
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9:17a, 6/19/20
AG
You wouldn't expect great antibody titers from mild cases.

You might expect that if you had a mild case before, that if you got reinfected that it would be mild again.

Also I know that titer is the way we measure immunity. That's because circulating antibodies do provide the best immunity. But it's also because it's the easiest thing to test. Long term immunity actually comes from having memory cells. Those are harder to test for.
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AgsMyDude
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In reply to Duncan Idaho • 9:20a, 6/19/20
AG
Can you link said article?
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Gordo14
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In reply to swc93 • 9:21a, 6/19/20
swc93 said:
Too much info and speculation really hurts the 'PR' for corona-virus and makes it even harder to convince the silent majority to take it seriously. While I appreciate ways scientist and doctors share new findings and fears; I know it just adds fuel to the whole fraud virus crowd. Downfall of sharing information I guess.

With the chance of the long term medical problems that can come along with this virus it would be devastating if some poor souls ending up catching it basically ever quarter.


What other solution is there though? A lack of information is worse and the problem is we just don't know everything. We need to act on probable or possible information or else we are far too late.

I think it leads to the problem of social media populism and how it encourages mistrust of experts in favor of cognative bias. People look for a specific answer they wany and then they get to high-five themselves and each other for thinking critically, while the experts on a subject matter get continually discredited for not knowing everything about a novel virus. It's really depressing.
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Duncan Idaho
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In reply to amercer • 9:21a, 6/19/20
Quote:

You might expect that if you had a mild case before, that if you got reinfected that it would be mild again.


What do you think would happen as you age?

If you had a mild case as a 30 yrs old, would you expect to have a mild reaction at 40, at 50, at 60?
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Gordo14
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In reply to Duncan Idaho • 9:24a, 6/19/20
Duncan Idaho said:
Gordo14 said:
https://www.cnbc.com/2020/06/18/coronavirus-antibodies-may-last-only-2-to-3-months-after-infection-study-suggests.html

This combined with only 6% of Sweden showing neutralizing antibodies does not bode well for the herd immunity solution. If (and I am by no means stating that this is science yet) we only have immunity for 2-3 months, letting the virus spread uncontrollably is a really dangerous strategy that I don't want to even get into the potential long term implications on. This is another reason why it is critical that we manage the spread of the virus in hopes of a vaccine in 7 months. Ignoring the virus is playing with fire - particularly in November-March.


Nature herd immunity is an OUTCOME. It is NOT a solution.

Saying it is a solution is like saying drowning was the solution to the number of life boats on the titanic.


Oh I agree. Admittedly my herd immunity "solution" comment was meant to come across as sarcastic. Again because long term immunity is a big question mark... And this paper doesn't offer any encouragement on that front.
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Duncan Idaho
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In reply to AgsMyDude • 9:24a, 6/19/20
AgsMyDude said:
Can you link said article?

I know nothing of the site. It was linked off drudge so take it for what it is worth.

https://futurism.com/neoscope/coronavirus-antibodies-fade-after-few-months
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amercer
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In reply to Duncan Idaho • 9:35a, 6/19/20
AG
Duncan Idaho said:
Quote:

You might expect that if you had a mild case before, that if you got reinfected that it would be mild again.


What do you think would happen as you age?

If you had a mild case as a 30 yrs old, would you expect to have a mild reaction at 40, at 50, at 60?


It's an interesting question. The obvious answer is that lots of old people die from infections that would be mild in young people.

On the other hand, if this turns into a yearly seasonal virus, the constant exposure will build some immunity even in repeated mild cases. One of the reasons that the flu doesn't kill everyone in years where they miss badly on the vaccine is that getting a vaccine every year build up long term immunity against all the strains. Boosting that immunity is great, but we've all got some.
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Diyala Nick
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9:38a, 6/19/20
AG
Your T Cells and B Cell Memory are felling very under appreciated right now.

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Ranger222
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9:44a, 6/19/20
AG
There are two arms to adaptive immunity -- the antibody response that gets a lot of the focus, specifically when we are talking about "immunity" and the best outcome for a vaccine candidate, but a lot of people are overlooking another critical part -- the T cell response. The Nature Medicine paper linked above only looks at antibodies. So far there was only been little research done to look at the T-cell response and prevalence of cross-reactive T-cells that would also provide protection from re-infection. You need both! Its very possible that just because antibodies wane over time, the presence of SARS-CoV-2 antigen-specific T-cells will be enough to do the job.

In fact, another (*non peer reviewed*) study posted yesterday suggests that the the interplay between B cell / T cell response is critical and you need a balance. Patients that experienced mild symptoms had a balance of B cell / T cells, but critically ill patients had CD4+ T cell response that was impaired. To make up for it, they made more antibodies! So antibody titer is not everything.....

Quote:
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the current coronavirus disease 2019 (COVID-19) pandemic. Understanding both the immunological processes providing specific immunity and potential immunopathology underlying the pathogenesis of this disease may provide valuable insights for potential therapeutic interventions. Here, we quantified SARS-CoV-2 specific immune responses in patients with different clinical courses. Compared to individuals with a mild clinical presentation, CD4+ T cell responses were qualitatively impaired in critically ill patients. Strikingly, however, in these patients the specific IgG antibody response was remarkably strong. The observed disparate T and B cell responses could be indicative of a deregulated immune response in critically ill COVID-19 patients.

https://www.biorxiv.org/content/10.1101/2020.06.18.159202v1

This is critical when we talk about vaccine studies as well. The antibody response will get the most headlines, but that doesn't mean the vaccine will be successful. You need a good T cell response as well and that never gets talked about and a lot of vaccine candidates fail that way! So far there was been no T cell data posted on vaccine candidates like Moderna's mRNA vaccine.
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AgsMyDude
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In reply to Duncan Idaho • 9:49a, 6/19/20
AG
Thanks! I assumed it was an external link
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amercer
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In reply to Ranger222 • 9:52a, 6/19/20
AG
I do wonder if you can expect the same sort of T cell response from these modern vaccines as you would from good old dead virus. When you pick part of the spike, or one coat protein you are really reducing the number of available epitopes.
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FlyRod
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10:00a, 6/19/20
Isn't COVID in the same family as the cold viruses? Which give you short term immunity...but then you can easily catch the cold again. If so, this conjecture isn't surprising.

I wonder if however it might behave like shingles: you get an outbreak but later ones are usually more mild...
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KlinkerAg11
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In reply to FlyRod • 10:20a, 6/19/20
AG
I'm of this opinion as well.
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swc93
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In reply to Gordo14 • 10:26a, 6/19/20
AG
Inherent danger of free press and access to information and this whole 'fake' news movement.
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murphyag
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10:32a, 6/19/20
AG
I heard some ladies at work this morning talking about a woman in Dallas who had Covid-19 early on. She was a person who had antibodies and donated a lot of her plasma to be used by other ill patients. Now, she apparently has somehow gotten Covid-19 again. The ladies at work said it was on the news. I'm going to look around after work and see if I can find anymore information about the woman.
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Ranger222
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In reply to amercer • 10:47a, 6/19/20
AG
Yes! That is why I have been skeptical of their mRNA vaccine....their is no data to suggest their platform will work overall. They conveniently left out any type of cellular response data on their Phase I "success" announcement and just talked antibodies...maybe they just haven't looked yet or maybe they don't want to.

Thats why if I had to place bets I like the idea behind Oxford's Chimp adenovirus vaccine, but no guarantees that will work either.

https://www.ovg.ox.ac.uk/news/covid-19-vaccine-development
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amercer
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In reply to Ranger222 • 10:56a, 6/19/20
AG
My wife is at AZ. Sadly I don't think that will get us first in line.

Just reading the tea leaves it seems like for Americans the moderna vaccines will be the first available.
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Beat40
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In reply to Gordo14 • 10:58a, 6/19/20
Gordo14 said:
Observer said:
If antibodies are only good for 2-3 months, then one has to be vacinated every 2-3 months?


Nobody knows. The point is we shouldn't be overconfident and pretend that the issue will solve itself. The virus isn't going away at this point. Let's do our best to manage it.


It does depend what your mean by "solve itself." If you mean that to be that it will go away, then no.

I would propose to you that the Spanish flu did end up solving itself by mutating into a weaker form.

In the end, this virus will ultimately solve itself. We can work to protect people, but nature will always work itself out one way or another.
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Windy City Ag
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11:01a, 6/19/20
AG
Quote:
I heard some ladies at work this morning talking about a woman in Dallas who had Covid-19 early on. She was a person who had antibodies and donated a lot of her plasma to be used by other ill patients. Now, she apparently has somehow gotten Covid-19 again. The ladies at work said it was on the news. I'm going to look around after work and see if I can find anymore information about the woman.

This woman is in my larger network. Her initial story (served up by her) was really sensational and the media picked up the ball and ran with it without questioning anything.

Meredith McKee is the woman's name. Her Facebook posts were the first thing I saw. She did a livestream where she was crying saying she contracted COVID for the second time.

The first thing that caught me was her claim that she tested positive in February. I knew that was off as the first positive case in the state was in Ft. Bend Country in early March and the first positive case in Dallas was not until March 9th. Maybe she was living on the West Coast . . I don't know. It sounds fishy though.

NBC 5 picked it up here initially and basically repeated everything she said verbatim. I noticed they have steadily walked back and amended a lot in the article. The first version did not include any medical opinion. They then put in an epidemiologist quote that questioned her statements. They then scrubbed a lot of the claims and had more medical commentary saying it might have happened but such an event is really rare.

https://www.nbcdfw.com/news/coronavirus/dallas-woman-battling-coronavirus-again/2389265/

Other media outlets including the Ny Post and People Magazine also ran her story.

https://people.com/health/dallas-woman-tests-positive-for-coronavirus-again/

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Duncan Idaho
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In reply to amercer • 11:43a, 6/19/20
amercer said:
My wife is at AZ. Sadly I don't think that will get us first in line.

Just reading the tea leaves it seems like for Americans the moderna vaccines will be the first available.
Assuming each is safe by themselves, would you expect there to be any danger in stacking the vaccines based on availability?

basically, Americans take the mdoerna for short term protection and then take the AZ vaccine when available for long term protection.
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amercer
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In reply to Duncan Idaho • 11:48a, 6/19/20
AG
Probably it would be fine?

That's the kind of thing you'd usually answer in a five to ten year long clinical program. But I think we should expect the unexpected when we are talking about rolling out multiple new vaccines at warp speed
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agforlife97
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11:49a, 6/19/20
AG
There is not going to be a vaccine in 7 months. It will be 2-3 years at minimum, and it's still a long shot even then. There has never been a successful coronavirus vaccine in humans or other animals. It's extraordinarily difficult in these types of viruses.

The fact that kids under 20 are largely immune or have low severity cases suggests that this study is bunkum IMO. And if the study is correct, it also implies that a vaccine has a low chance of success.
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Duncan Idaho
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In reply to amercer • 11:54a, 6/19/20
amercer said:
Probably it would be fine?

That's the kind of thing you'd usually answer in a five to ten year long clinical program. But I think we should expect the unexpected when we are talking about rolling out multiple new vaccines at warp speed
why i used the word "expect"
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Gordo14
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In reply to Beat40 • 12:43p, 6/19/20
Beat40 said:
Gordo14 said:
Observer said:
If antibodies are only good for 2-3 months, then one has to be vacinated every 2-3 months?


Nobody knows. The point is we shouldn't be overconfident and pretend that the issue will solve itself. The virus isn't going away at this point. Let's do our best to manage it.


It does depend what your mean by "solve itself." If you mean that to be that it will go away, then no.

I would propose to you that the Spanish flu did end up solving itself by mutating into a weaker form.

In the end, this virus will ultimately solve itself. We can work to protect people, but nature will always work itself out one way or another.


Sure. There are ways to make the damage less significant for the time being. The problem with waiting for the mutation into a weaker form is that this virus mutates much slower than influenza. This virus is contagious enough to forcibly shut us down - which is why we need prudent measures to slow the spread for the time being. And I am not recommending everybody weld themselves into their homes... Just don't do stupid **** that can accelerate this further... that might be enough.
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Gordo14
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In reply to Ranger222 • 12:47p, 6/19/20
I am aware that antibodies are not the extent of the immune system. But we know we don't have lasting immunity to other coronaviruses. In addition, we know the antibodies seem to be disappearing relatively quickly. My post was not about bring definitive about long term immunity, but a reminder that our inmunity may not be long lasting particularly to reach "herd immunity". So maybe we need to carefully consider how apathetic we are to this virus and it's spread even if it's manageable today.
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DadHammer
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In reply to Gordo14 • 11:27a, 6/20/20
AG
If that were true then Italy, Spain, France, and other hard hit countries would be showing lots of reinfections.

They are not at this time.
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