Can someone update the latest data regarding Covid immunity?

I keep reading that those infected and recovered only have immunity for a few months before becoming vulnerable again and that the vaccines in development have the same shortfall.

is that all we can look forward to at the moment--temporary protection?

ramblin_ag02 said:

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Sporadic cases of reinfection have been documented, always by different strains. It's very difficult to document reinfection with the same strand so that part is not really known.

On the plus side, we haven't seen any significant levels of readmissions among recovered people. So the best thought so far is at least 8 months of immunity so far, counting from Italy's outbreak. I still don't believe any Chinese data from January

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I had covid in May. I would have had them test me last week, but didn't fit into the requirements they have for testing and they no longer test here except with doctor's orders or if you have certain symptoms. Problems resembling allergies are apparently not included on their list of symptoms.

The doctor I go to uses a PCR test. In my county, they use some test that gives results in about 20 minutes. I could have made an appointment to go get a test and I didn't think it reasonable to make a doctor's appointment here to get a test so that I could make a doctor's appointment to my regular doctor.

So I went to the regular doctor for allergies on Friday afternoon thinking that if they want to test me, it's up to them. I ended up talking to a nurse practitioner instead. She did ask if I have had a sore throat since the back of my throat was red but I haven't had any sore throat.

Anyway, she said that they would test me for covid if I wanted and I replied that I really didn't see the point in it at that time. My reasoning is that since I had been having those problems for a week and a half, if it was due to covid I would likely be out of isolation before we ever got the test results. She sounded rather irritated at that and claimed that if I was tested and it came back positive, I would be in isolation for at least the next ten days. My symptoms (if they were of covid rather than a simple allergy) began on Monday and Tuesday of the week before. By the CDC guidelines, it's ten days from the start of symptoms, not the test, and at least one day after the fever ends (which I never had) and a significant improvement in symptoms (my allergy symptoms I was having have pretty much gone now). And, of course, if it wasn't covid, then it didn't matter anyway.

tldr: I don't think I had covid again, but can't rule it out.

GAC06 said:

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You didn't get it again

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I doubt that I had it, but there were definite similarities between the last two weeks and when I had it in May. The only real difference was that I didn't have any disturbances in my sense of smell.

GAC06 said:

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That's a whole lot of typing and nothing about getting it twice

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Unless covid is magical, it shows that the idea that getting twice has the same odds as getting struck by lightning twice is completely insane.

Oh ok, then show me all the people that have gotten it twice. Since it's one in 25 in your county, and people like you have no antibodies, there should be lots of people getting it a second or third time. So show them to me.

GAC06 said:

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Oh ok, then show me all the people that have gotten it twice. Since it's one in 25 in your county, and people like you have no antibodies, there should be lots of people getting it a second or third time. So show them to me.

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Once again, covid is not distributed randomly.

A large majority of the cases in my county are from the last month and a half or so. If someone is going to get it twice, they are almost surely from the much smaller number who had it more than three or four months ago. Furthermore, many of those who had it likely developed antibodies to it. At least some of the estimates are that 20% or so don't develop antibodies.

If covid is distributed randomly as you seem to believe, the odds make it unlikely that anyone in the county has yet to have it twice. With the actual clumping of cases, those odds could be higher if those who got it early one are more likely to deal with others who have it or lower if those who got it early are more careful to avoid being exposed again.

For most of those who have had it in the county, look to see what is happening several months from now.

There's also the question of t-cell immunity. I get the impression that nobody really knows what to expect for t-cell immunity.

I think traceable antibodies can wear off but it doesn't mean your body won't create them if you were to get covid again.

Meaning I think you might not even know you had it the second time.

I realize it's still very early days since the advent of Covid 19 and the scientific/medical community is learning something new about the virus almost every day.

With that in mind, articles like the one I just posted above formed the basis for my OP and the wide variety of responses since only confirm that no one has a definitive answer about durable immunity just yet.

It's likely that you won't get re-infection for 1-2 years. Some will be outliers on that, which we'll see a handful of. People will catch and die of CV19 just like they do a number of other respiratory diseases for a long, long time.

Quote:

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"Our study shows that over time there is a reduction in the proportion of people testing positive for antibodies," Paul Elliott, study author and professor at Imperial College London, said in a university news release. "It remains unclear what level of immunity antibodies provide, or for how long this immunity lasts."

The study and university release included suggestions over declining immunity.

"These findings suggest that there may be a decline in the level of immunity in the population in the months following the first wave of the epidemic," per the university release. Likewise, the study says: "These data suggest the possibility of decreasing population immunity and increasing risk of reinfection as detectable antibodies decline in the population."

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https://www.foxnews.com/health/study-suggests-coronavirus-immunity-drops-after-3-months

LawHall88 said:

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Quote:

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"Our study shows that over time there is a reduction in the proportion of people testing positive for antibodies," Paul Elliott, study author and professor at Imperial College London, said in a university news release. "It remains unclear what level of immunity antibodies provide, or for how long this immunity lasts."

The study and university release included suggestions over declining immunity.

"These findings suggest that there may be a decline in the level of immunity in the population in the months following the first wave of the epidemic," per the university release. Likewise, the study says: "These data suggest the possibility of decreasing population immunity and increasing risk of reinfection as detectable antibodies decline in the population."

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https://www.foxnews.com/health/study-suggests-coronavirus-immunity-drops-after-3-months

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This is the third study cited so far here suggesting that immunity may fade quite quickly. Hence my OP.

Did some searching a while back about this and read a few articles that went over my head. Funny quote from one of the immunology doctors/researchers in the comments was that we really don't understand how the immune system and all it's moving parts work at it's deepest levels and this is all very complicated. He explained it this way.

"An immunology board game would have a rulebook that's 600 pages long and is written only in acronyms; there's a cupboard's worth of tokens; and every so often, the board spontaneously catches fire."

BTW Epidemiologists don't really study or understand immunology. There is more to it than antibodies and antibody testing.

ShinerDunk93 said:

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Did some searching a while back about this and read a few articles that went over my head. Funny quote from one of the immunology doctors/researchers in the comments was that we really don't understand how the immune system and all it's moving parts work at it's deepest levels and this is all very complicated. He explained it this way.

"An immunology board game would have a rulebook that's 600 pages long and is written only in acronyms; there's a cupboard's worth of tokens; and every so often, the board spontaneously catches fire."

BTW Epidemiologists don't really study or understand immunology. There is more to it than antibodies and antibody testing.

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Much of medicine is still equal parts science and art.

Varying studies continue to leave durable immunity open to question. How Long?

Has Pfizer said if its new 90%-effective vaccine will provide durable immunity or if annual boosters will be necessary?

The original SARS COV-1 patients retained immunity for 3+ years. I expect SARS COV-2 antibodies will remain at least that long due to similarities between the two viruses.

You might need a second dose at some point in your life, likely long after the virus disappears

You can get the flu even if you had a flu shot.

You can get the flu more than once in a flu season.

You need a flu vaccine once per season.

Not sure why covid as a respiratory illness or immune trigger would behave differently. The flu has multiple strains and Covid will too, which allows multiple infections in a season. Unlikely, but not impossible. I'd also assume immunity will vary widely person to person due to health, genetics, on and on.

ShinerDunk93 said:

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Did some searching a while back about this and read a few articles that went over my head. Funny quote from one of the immunology doctors/researchers in the comments was that we really don't understand how the immune system and all it's moving parts work at it's deepest levels and this is all very complicated. He explained it this way.

"An immunology board game would have a rulebook that's 600 pages long and is written only in acronyms; there's a cupboard's worth of tokens; and every so often, the board spontaneously catches fire."

BTW Epidemiologists don't really study or understand immunology. There is more to it than antibodies and antibody testing.

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Definitely like the quote. Google suggests this is the source

One observation after spending lots of time trying to develop the most basic grasp of Virology and Immunology is while people may use the same words, the intuition and mental models they are working with are quite different. Some of this is the standard layman vs expert problem. Yet, I suspect there is more going on.

Take as an example the thread title "Immunity." People have an idea what they believe the word means. However, a little poking around shows that people aren't using the word to convey the same ideas. Add to that the dearth of actual data and you get a weird mix of certainty and uncertainty all on some seemingly shaky ground.

As an example, take the common knowledge that "immunity" for the common cold coronaviruses disappears within a year. Shane Crotty a seemingly distinguished virologist/immunologists disagrees with that accepted truth. You can hear his short discussion of this at 26:30 on a This Week in Virology Podcast

https://www.microbe.tv/twiv/twiv-657/

The paper he cites as the basis for the commonly accepted idea that immunity for common cold coronaviruses disappears with a year is this

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2271881/pdf/epidinfect00023-0213.pdf

Abstract

After preliminary trials, the detailed changes in the concentration of specific circulating and local antibodies were followed in 15 volunteers inoculated with coronavirus 229E. Ten of them, who had significantly lower concentrations of pre-existing antibody than the rest, became infected and eight of these developed colds. A limited investigation of circulating lymphocyte populations showed some lymphocytopenia in infected volunteers. In this group, antibody concentrations started to increase 1 week after inoculation and reached a maximum about 1 week later. Thereafter antibody titres slowly declined. Although concentrations were still slightly raised 1 year later, this did not always prevent reinfection when volunteers were then challenged with the homologous virus. However, the period of virus shedding was shorter than before and none developed a cold. All of the uninfected group were infected on re-challenge although they also appeared to show some resistance to disease and in the extent of infection. These results are discussed with reference to natural infections with coronavirus and with other infections, such as rhinovirus infections.

If you read the Abstract closely you will see Crotty's point.

So does "immunity" mean avoiding infection or avoiding disease or avoiding being contagious or something else? And how much do we really know about most virus/diseases?