quote:
Upon infection, most viruses trigger a vigorous immune response from both arms of the immune system: a lymphoid response and a myeloid response. Interferons released from infected cells trigger the lymphoid response, resulting in antivirus antibodies which bind to and eliminate the virus from the body. T cells are also activated that can recognize and eliminate infected cells.

The myeloid pathway works differently. Myeloid cells attack the virus and the infected cells directly. Some myeloid cells engulf and destroy virus particles, others kill the infected cells directly, and others still induce a protective inflammatory response by release of compounds called cytokines.

The way SARS-2 affects both arms of the immune response is different from other viruses. The lymphoid pathway is muted and the myeloid pathway hyperactive. This helps explain why some people who recover from Covid-19 have very low, sometimes undetectable levels of anti-SARS-2 antibodies, and others have undetectable levels of “neutralizing” antibodies capable of the inactivating virus in laboratory experiments.

quote:
In dampening the antibody response to infection and ramping up production of chemokines, SARS-2 is amplifying what happens to us naturally as our immune systems age. While our ability to mount an effective antibody and T cell response to new infections declines, the myeloid arm of the immune system becomes overactive. These features of the aging immune system account for both the decline in our response to new vaccines and to an increase in inflammatory auto-immune disease such as rheumatoid arthritis.

https://www.forbes.com/sites/williamhaseltine/2020/05/27/a-nasty-trick-in-the-covid-repertoire/#696d181c69e6

Nevada case may be similar as well as just being a false positive first time around for the guy reinfected (weeks after first infection retested twice with negative results probably to clear him but article wasn’t clear if he had multiple positive tests before negatives or why 2 negative tests needed & not sure about him having antibody tests). Even if truly infected and virus caused muted antibody response first time around Given worldwide numbers of infections situations are rare. Biggest take I had was just because someone confirmed with a positive virus result versus just considered likely and stayed home for 10 days they shouldn’t automatically assume they have antibodies (because official positive test results)and should get tested antibodies.

This post was edited on 10/13/20 at 5:54 pm