We have seen promising non-human primate studies on lack of re-infection in antibody monkeys.

This is an apolitical thread dedicated to links, discussion, or any info on studies that have been done on humans (I can't find any). Ultimately looking for some type of quantitative/statistical findings that show reinfection does or does not occur at some rate.

*If there is info on enrolling in any antibody studies that is also welcomed.

This was a super easy straight forward study on monkeys below. In a world were people donate marrow, organs, etc, I would hope we could gather groups of people who had mild flu like symptoms or less, to be subjects in similar studies. I get the red tape/liability and such, but if there was ever an exceptional need to adjust rules, now would be time.

https://pubmed.ncbi.nlm.nih.gov/32616673/

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Comparing the humoral and cellular immunity between primary infection and rechallenge revealed notably enhanced neutralizing antibody and immune responses. Our results suggest that primary SARS-CoV-2 exposure protects against subsequent reinfection in rhesus macaques.

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Thanks KD, great recent video. Interesting discussion on T cells vs antibodies, and other general coronavirus mechanisms working in children building an immune system. Also, great point on herd immunity threshold being lower than thought, due to cross coronavirus exposure and t cells.

I would just think at this stage, we would be further along and experts would not be glossing over re-infection as merely "anecdotal stories". If there was NOT a dominant t-cell or antibody response, I think we would have much more than "anecdotal stories". The final step would be testing some humans at some point...

thirdcoast said:

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Thanks KD, great recent video. Interesting discussion on T cells vs antibodies, and other general coronavirus mechanisms working in children building an immune system. Also, great point on herd immunity threshold being lower than thought, due to cross coronavirus exposure and t cells.

I would just think at this stage, we would be further along and experts would not be glossing over re-infection as merely "anecdotal stories". If there was NOT a dominant t-cell or antibody response, I think we would have much more than "anecdotal stories". The final step would be testing some humans at some point...

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Like this article from June?

https://jamanetwork.com/journals/jama/fullarticle/2767024

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espite the potential risks, more than 25 000 volunteers from 102 countries had signed up to participate in a challenge trial less than 6 weeks after the 1 Day Sooner website launched on April 17.
"I just want this to be solved already," a volunteer from Romania commented online.
Morrison and other proponents of challenge trials argue that exposing young, healthy people, a population that appears to have the lowest risk of dying from COVID-19, is no more dangerous than the accepted practice of allowing them to donate a kidney or liver lobe.
"It's not every day that doctors intentionally give a pathogen to study participants," acknowledged Rutgers University bioethicist Nir Eyal, DPhil. Eyal is part of an informal working group advocating for human challenge trials involving volunteers aged 20 to 29 years. Based on COVID-19 cases from February, a recent study estimated that 0.03% of people in that age group who were infected with SARS-CoV-2 died, and 1.1% were hospitalized. Rates were substantially higher in older age groups.
Eyal and 2 of his working group colleagues first raised the subject of human challenge studies for COVID-19 vaccine candidates in the article that sparked Morrison's interest. In it, they suggested that a global pandemic changes the ground rules for clinical trials. Given the circumstances, they wrote, challenge studies might be an acceptable way to bypass phase 3 trials, the final stage of assessing safety and effectiveness before the US Food and Drug Administration (FDA) considers whether to approve a vaccine or drug. Phase 3 trials typically enroll several thousand people who must be observed long enough in the field to determine whether people in the vaccine group developed fewer infections than those in the control group, Eyal and his coauthors noted.

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I'm less interested in vaccine trials and more interested in re-infection studies like what they did with monkeys.

Anyway, I'll check back in and let y'all know if anything comes of my submission below. My screenshot was the Gulf Coast blood center result showing I was indeed positive with antibodies since mid-late June.

https://www.centexstudies.com/read-more-trial/RMg2JemG8Q

Nice, thanks

So if I read this correctly the study shows a 1% reinfection rate (3 out of 285) or a 0.4% reinfection rate (3 out of 790)?

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For the 285 re-positive cases investigated, 790 contacts were found in total. Minimum 14-day monitoring found 27 of the contacts to be positive, 24 of which were cases that were previously confirmed.

There were 3 newly confirmed cases from the 790 contacts of re-positive cases.

- Other than their exposure to the re-positive cases during their respective re-positive period, all of the 3 newly confirmed cases had history of contact with Shincheonji religious group or a confirmed case in their family.

- Virus isolation cell culture result was negative for 2 of the newly confirmed cases. (Viral cell culture test was not possible for 1 case as the PCR result was indeterminate.)

- In all re-positive cases and newly confirmed cases, neutralizing antibody production was found from the first serum.

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My interpretation was the only 3 of the 790 people who were in contact with "re-positive" patient were infected. So this is an indication that perhaps these re-positive cases are not transmitting to other people much at all.

I think that there have been 447 "re-positive" cases out of South Korea's 14,092 cases. I think it is hard to know how many of these are re-infections vs a persistent infection that might be at a low level (leading to some false negatives). I think that is why they are calling them "re-positive" instead of "reinfected."

It's also hard to know their ability to detect reinfection. But South Korea is performing a large number of tests per every positive test, and being very aggressive about contact tracing. So, I think they should have pretty good ability to detect reinfection (though they have a low # of primary cases...).

CompEvoBio94 said:

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My interpretation was the only 3 of the 790 people who were in contact with "re-positive" patient were infected. So this is an indication that perhaps these re-positive cases are not transmitting to other people much at all.

I think that there have been 447 "re-positive" cases out of South Korea's 14,092 cases. I think it is hard to know how many of these are re-infections vs a persistent infection that might be at a low level (leading to some false negatives). I think that is why they are calling them "re-positive" instead of "reinfected."

It's also hard to know their ability to detect reinfection. But South Korea is performing a large number of tests per every positive test, and being very aggressive about contact tracing. So, I think they should have pretty good ability to detect reinfection (though they have a low # of primary cases...).

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Nice....guess we will keep seeing what the Koreans put out. Wish math was valued at the same level here.

FYI, got a call back from my submission and they said they are now only taking healthcare workers for studies on re-infection. They took my info and told me I would be added to call back list for future studies.

I guess they aren't doing controlled studies, but instead just seeing if those people likely exposed naturally are getting re-infected. I would assume if healthcare workers were getting re-infected they would be all over CNN and MSNBC every night primetime.

Yes, anything negative gets run by them non stop