Updates on #COVID19 Serology

Antibody survey data is increasing [All have limitations: hotspots are not representative, some tests may have false positives]

However, LA, Boston, NYC, Santa Clara, Netherlands, ..., now evidence potential transmissibility of the virus...

1/6

Seroprevalence in LA, Santa Clara, Netherlands have ~3+%. and suggest wide transmission

(Recognizing that these may not all be accurate)

These %s are early April & antibodies form ~10+ days post virus exposure. So most exposures measured happened before March ~25.

2/6

Since March ~25, >3x more cases have occurred in these places. Today these populations may have >10% cumulative incidence.

More recently, area of MA had ~30% positivity and one area of NYC, 15% of a pop were positive for virus - antibody results would be higher...

3/6

All these places are densely populated "hotspots"

However the pattern that emerges is that we underestimate the transmissibility of this virus

This has implications for everything from how to contain it, how it affects us biologically, how and when we get back to work…

4/6

However, as @BillHanage points out well – priority number 1 is getting this virus under control. Only then should we worry about the absolute individual-level risk associated with infection because what we do know now is that population risk is very high.

5/6

Only after transmission is well controlled, then we can start plotting the path of the future.

And this will incorporate serological studies now underway, individual and population-level risk, testing availability, and of course major societal/economic considerations

6/6

And here's the tweet thread from @BillHanage I referenced above: https://twitter.com/BillHanage/status/1252415652393971718?s=20