Before you read further, this is a bullshit article. I post it as a caution in reading articles of this sort.
Yes, it says antibodies fade quickly, citing a half-life of 73 days (news to me, but plausible) It then goes on to speculate that maybe that is not so bad as it looks, without citing any data or studies to back that statement. I certainly hope this speculation is correct, but for folks who don’t read critically, it reads as though this is a known thing. It is not. This kind of reporting is irresponsible at best.
If Walmart offered a 50 cent discount to anyone who wore a mask from the time they entered the store until they left, these guys would be masked up the whole time.
Maybe? The trouble is trying to project long term outcome on short term data. We have one dataset showing that asymptomatic to mildly symptomatic people generate antibodies that start to fade after about 2 months. This study funds that in mild to moderate cases (note slightly different population) antibodies seem to be stable up to 3 months. More severe infection may generate more durable immunity, or the difference in these duration data may be statistically similar. As always, WDKS and more info is needed.
The high seroprevalence at the start of the study makes me wonder about false positives in the ELISA. I didn’t see discussed any attempt to confirm ELISA with a virus neutralization test. Since the plasma in the study was collected for a (separate) convalescent plasma study, they have to have run VNT on some subset of the samples, I presume, so perhaps this information was omitted from the preprint. (Or is it even possible to do neutralization tests at this point? Do we have 2019-SARS-CoV-2 growing stably in cell culture?)
Even if the neutralizing antibody response fades, that’s not that great a surrogate for patient immunity. We use it because we can measure it. Few patients immunized against smallpox have any measurable level of circulating antibodies after a year, but the immunity (thought to be CD8+ T-cell-mediated) lasts for decades.
Of course, CD8+ T-cell-mediated immunity won’t have any effect on convalescent plasma, since the cytotoxic lymphocytes aren’t being transfused, so it’s meaningless for the real purpose of the Mount Sinai study.
Since March here, probably in other level 3 containment facilities. (Tricky times for those facilities. They don’t want anything to get out, and they don’t want anything brought in either.)
Sorry I didn’t make myself clear - emphasis was on the ‘stably’. I know we have it growing in culture; is its infection and replication rate stable enough to support quantitative neutralization studies?
I’ve worked from time to time in BSL-3 facilities. (I’m not a biologist. I’m an electronics geek with a seriously weird gig.) It’s always a tricky time. 2019-SARS-CoV-2 might be new, but strange and deadly pathogens are those labs’ stock in trade.
Here is a deeper dive into the immune response to covid, and some details of WDKS, but also some places that offer some encouragement. In the end, we are “gonna science the shit out of it.” The question is what sort of timeline are we looking at, and that, for the time being, is truly an unknown.
If there is one good thing that will come out of this it will be that. We have known about human coronaviruses since the 1930s, but as long as the death-count was low, they weren’t a priority. We will probably have discovered more in this one year than the entire last decade, if not the last five. I wish it hadn’t taken an all out deadly plague to make it happen, but that’s what you get when the pursuit of knowledge is ruled by profit.
