Quarantine Alone or in Combination with Other Public Health Measures to Control COVID-19: A Rapid Review

Background COVID-19 (coronavirus disease 2019) is a new, rapidly emerging zoonotic infectious disease, that was reported to the World Health Organization for the first time on 31 December 2019. Currently, no effective pharmacological interventions or vaccines are available to treat or prevent COVID-19, therefore nonpharmacological public health measures are more in focus. Objectives The aim was to assess the effects of quarantine alone or in combination with other measures - during coronavirus outbreaks. Methods Because of the current COVID-19 pandemic, WHO commissioned a rapid review. To save time, the method of systematic reviews was slightly and with caution modified. This publication is a summary of the most important aspects of the rapid review, translated into German by members of the WHO Collaborating Centre at the Danube University Krems (Austria). Results Overall, 29 studies were included. Ten modeling studies focused on COVID-19, 4 observational studies and 15 modeling studies focused on SARS and MERS. The modeling studies consistently reported a benefit of the simulated quarantine measures. For example, the models estimated that quarantine of people exposed to confirmed or suspected cases of COVID-19 prevented between 44 and 81 % of the cases that would otherwise have happened and 31 to 63 % of the deaths, when compared to no such measures. In regard to costs, the earlier the quarantine measures are implemented, the greater the cost savings will be. Conclusion Our confidence in the evidence is very limited. This is mainly because the COVID-19 studies based their models on the limited data that have been available in the early weeks of the pandemic and made different assumptions about the virus. The studies of SARS and MERS are not completely generalizable to COVID-19. Despite only having limited evidence, all the studies found quarantine to be important for controlling the spread of severe coronavirus diseases. Looking to the coming months, in order to maintain the best possible balance of measures, decision makers must continue to constantly monitor the outbreak situation and the impact of the measures they implement.