Thread by @AbraarKaran

THREAD

1/ New CDC report on #covid19 outbreak -55 cases in a week- among those attending an exercise facility in Chicago in August 2020...

22 people (40%) attended on or *after* the day their symptoms started

76% reported wearing masks *infrequently*
cdc.gov/mmwr/volumes/7…

2/ Right in the abstract here under "implications for public health practice", CDC says:

"To reduce SARS-CoV-2 transmission in fitness facilities, attendees should wear a mask, including during high-intensity activities when ≥6 ft apart."

So the 6 foot rule has limits...why?

3/ Because of smaller particles- aerosols- that spread farther than six feet, & hang around for more than 15 minutes.

And CDC acknowledges that; but is still hesitant to send people #BetterMasks (announced today they are sending cloth masks)? C'mon man. What is going on?

3.5/ "Although the timing of cases suggests a point-source exposure, none was identified. Most interviewees attended several exercise classes.

Some published evidence supports aerosolized transmission of SARS-CoV-2, which could have been a contributing factor in this outbreak"

4/ "Although the facility’s ventilation system was not assessed, inadequate air circulation might have exacerbated transmission in the building, which was not originally designed for exercise classes" #covid19

Better ventilation. #betterMasks. We need these in the community.

4.5/ "In addition, facilities should provide engineering & admin controls incl 1) improving ventilation; 2) enforcing consistent + correct mask use & physical distancing (maintaining ≥6 ft of distance b/w all persons & limiting physical contact, class size, & crowded spaces)"

5/ "All classes were held at ≤25% capacity (i.e., 10–15 persons). Mask use, temperature checks, and symptom screenings were required on entry; however, patrons were allowed to remove masks during exercise."

**Why would they focus on temp checks but not require masks?**

6/ Big take-aways/reminders:

-#covid19 spread happens within AND beyond 6 ft; 15 mins

-#Bettermasks and better ventilation = better protection

-Rigorous exercise--> more emission of droplets & aerosols

-Temp checks/ sx screening --> won't catch pre-symptomatic cases...