Thread by @AbraarKaran

THREAD
1/ NEW CDC report on secondary attack rate of #covid19 in the home — overall above 50% in this study; families prospectively followed out for 7 days w/ daily tests; important implications for safer isolation options/rapidity of spread right at home

cdc.gov/mmwr/volumes/6…

2/ During my time working in the #covid19 emergency room during the first Boston surge in April, the *majority* of cases that I personally saw were likely infected by someone at home who was already a known case. See op-ed here : washingtonpost.com/outlook/2020/0…

3/ issues with home based transmission—> psychologically people may feel safer at home than they actually are; less likely to mask up; bad combo if strict isolation of cases is not possible (largely isn’t for most people)

But isolating outside the home also not popular

4/ While we tried to have safer isolation options such as the Boston Hope field hospital, many patients preferred to isolate at home w/ their loved ones; and unsurprisingly this didn’t always work out as planned/ likely led to family based clustering.

massgeneral.org/news/coronavir…

5/ Authors point out that 75% of secondary infections were detected within 5 days of index case; also point out that index cases of both children & adults had high secondary transmission.

Also <50% family members reported any symptoms when their infection was detected

6/ The secondary attack rates here much higher than a number of other studies that are closer to ~15%...

Authors point out many of those studies did not have the same level of follow up monitoring and testing that this study had.

7/ In WHO Wuhan investigative report, family based clustering was noted as important for transmission of #covid19 which is why quick isolation away from the home was a key part of their strategy— that was something we *did not* do well here. Still aren’t doing it well.

8/ Again— a tough issue especially when isolation options that are provided outside the home aren’t appealing/ people don’t trust the government or being taken to a different facility away from their family. These are legitimate barriers that need to be addressed.

9/ Also hits on importance of masking *inside the home* if someone is sick or exposed to #covid19 and cannot safely quarantine or isolate. Also likely to worsen inequities as more crowded smaller households will run into this issue far more.

Cc @lisalsong @rkwadhera @edyong209 @CarolineYLChen @kakape @HelenBranswell @apoorva_nyc @zeynep @RanuDhillon @ReganHMarsh @IngridKatzMD @rajpanjabi @EpiEllie @BhadeliaMD @syramadad