- Early quarantine combined with other preventative public health measures (e.g., physical distancing, community closures) forms the optimal strategy for reducing COVID-19 morbidity and mortality.
- Evidence grade is low-very low in this Cochrane rapid analysis.
Why this matters
- Quarantine alone might be insufficient to contain SARS-CoV-2 transmission and acquisition.
- Especially those with suspected exposure should practice physical distancing, avoid community gatherings, and quarantine as much as possible.
- 29 studies (10 on COVID-19, 15 SARS, 2 SARS/other infectious diseases, 2 MERS).
- With quarantine only:
- Case reductions (4 studies) from 44% (COVID-19) to 81% (SARS).
- Mortality reductions (2 studies) from 31%-34% (COVID-19) to 63% (SARS).
- Quarantine + other measures (4 studies):
- +case isolation, social distancing: 67% case reduction (ages ≥70, 1 study).
- +closures, mass gathering cancellations, travel restrictions: R 0 reduced from 2.9 to 2.3 in 2 weeks (1 study).
- +closures: peak of onward transmission reduced by 29.9%.
- +restricting travelers from ongoing outbreak countries: small effect.
- Cochrane rapid review evaluating effects (transmission, mortality, resource utilization) of quarantine alone or in combination with other measures in:
- Contacts of confirmed/suspected COVID-19 or persons living in high transmission areas;
- Returning travelers from countries with declared outbreaks.
- Funding: Cochrane Collaboration.
- Time constraints.
- Titles limited to English, Chinese languages.
- Confounding likely.