🦠JUST IN: You May Have Antibodies After Coronavirus Infection. But Not for Long. Antibodies to the virus faded quickly in asymptomatic people, scientists reported. That does not mean immunity disappears. 🧵 nytimes.com/2020/06/18/hea…
2) There’s actually 2 studies. One found that 20% of cases asymptomatic and 1/3 of the asymptomatic had “ground glass opacities” in lung scans (damage). And asymptomatic have lower concentration of antibody, but longer to shed... 
3) Also “even low levels of certain antibodies have potent neutralizing capability”, and “might suggest that these asymptomatic patients are indeed capable of transmitting virus”
4) Also keep in mind that your memory B cells, which is a library archive of past infections that your body can make antibodies for, can rapidly ramp up antibody production when needed.
“If they find the virus again, they remember and start to make antibodies very, very quickly”
“If they find the virus again, they remember and start to make antibodies very, very quickly”
5) antibodies to one viral protein dropped below detectable levels. But a second set of antibodies targeting the spike protein of the 🦠— needed to neutralize & prevent reinfection — were still present. Neutralizing antibodies seemed to show a smaller decline in asymptomatica.
6) as for virus shedding, “It is important to know if they are shedding infectious virus, or just remnants of the virus,” said Akiko Iwasaki, a viral immunologist at Yale University.
But, Dr. Iwasaki was more concerned than the other experts about the two new studies...
But, Dr. Iwasaki was more concerned than the other experts about the two new studies...
7) “These reports highlight the need to develop strong vaccines, because immunity that develops naturally during infection is suboptimal and short-lived in most people,” she said.
➡️ “We cannot rely on natural infection to achieve herd immunity.”
➡️ “We cannot rely on natural infection to achieve herd immunity.”
8) Reading these, it seems there is still disagreement between some virologists and immunologists about virus shedding, whether truly infectious, and if antibody offers long term protection or not. But neutralizing antibody being more longer lasting in asymptomatic is hopeful.
9) However, many experts think “The neutralizing antibody is what matters”. And neutralizing antibody is what NIH checks for as well in phase 1 trials and in vaccine research. But this can only be tested in advanced labs like NIH or specialized virology labs.
