1/ This is important & has been discussed extensively among many ID docs, aerosol scientists & epi colleagues — #covid19 is spread through both droplets AND aerosols - the latter which don’t follow a “6 feet” rule, esp indoors/poor ventilation/cloth masks

https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/how-covid-spreads.html

2/ The question remains to what extent and in what situations #covid19 is spread via droplets vs aerosols; also has big implications for what scenarios especially need better masks than solely cloth.

In May and in June, @RanuDhillon @sri_srikrishna and I wrote about this issue.

3/ Especially in settings like workplaces & schools, & in the fall/winter when more activity moves indoors, & crowding becomes less avoidable, a combination of better ventilation, better masks, & rapid tests will most likely additively help reduce the risk of transmission.

4/ There is back/ forth on Twitter now about whether this is a change or isn’t a change— I personally had not seen CDC acknowledge small particle transmission in writing as a common route of spread.

Many questions, incl relative role of short range v. long range aerosols etc

5/ But, I do think this is relevant in terms of the strategies & communication around transmission.

Because many states have indoor dining, indoor gatherings, still saying “6 feet” w/o more details, no rapid testing strategy, & still tell people to fold up cloth t-shirts.