Every January, at the Washington, DC Convention Center, 15,000 people gather to exchange memes and viruses. I have attended most of the events held over the past 30 years. It seems like I get sick from most of those.

This year, I conducted a Twitter Poll to see if I was alone. The results below

Are you sick of TRB? A poll about the 2020 Washington DC Conference. Did you go this year, or not? And did you get cold or flu symptoms, or not, in the past six weeks?

16.9% TRB, ill

33.1% TRB, not ill

7.7%   Not TRB, ill

42.3% Not TRB, not ill

142 votes · Final results

The evidence from this poll of more than 142 people (coincidentally evenly split between TRB and non-TRB goers) is that you are more than twice as likely to report having gotten sick if you attended TRB (33.8%) than otherwise (15.4%). There were 71 attendees and non-attendees each in the sample, you can decide if that is sufficiently large to draw this conclusion. Obviously correlation is not causation, and there can be other causes:

• Twitter users are hypochondriacs, easily suggestable and are faking illnesses after this was raised,
• TRB attendees are world travelers (compared to non-attendees) and may have gotten sick elsewhere as well (which mitigates but does not absolve the Annual Meeting, as TRB is part of world travel they engage greater than the general population)
• TRB attendees got sick from air and train travel, rather than the conference itself.

Nevertheless, I tend to believe these findings, they align with my priors and have an underlying mechanism. We can validate next year and with other conferences.

If it turns out we had coronavirus all along (for months prior to being aware of it), (people who are not dropping over dead or feeling the need to be hospitalized are not being tested in most of the world, indicating the death rate given the virus is probably much lower than reported, deaths are mostly known (though perhaps some are misclassified), cases are not) this might have been a major vector of transmission.

So in addition to the other known negative externalities of attending conferences, such as the pollution generated, we can add health effects. Do these outweigh the benefits from in-person exchange of knowledge?