Key Points
Question
What is the household secondary attack rate for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)?
Findings
In this meta-analysis of 54 studies with 77 758 participants, the estimated overall household secondary attack rate was 16.6%, higher than observed secondary attack rates for SARS-CoV and Middle East respiratory syndrome coronavirus. Controlling for differences across studies, secondary attack rates were higher in households from symptomatic index cases than asymptomatic index cases, to adult contacts than to child contacts, to spouses than to other family contacts, and in households with 1 contact than households with 3 or more contacts.
Meaning
These findings suggest that households are and will continue to be important venues for transmission, even in areas where community transmission is reduced.