Background: To fight against COVID-19, many policymakers are wavering on stricter public health interventions. However, relying on these measures but different strategies, both in and out of China’s Hubei province basically contained the epidemic in late February 2020. This study aimed to assess the response process and estimate time-varying effect of Hubei control strategy to provide insights for intervention design and implementation.
Methods: We retrospectively compared the spread and control of COVID-19 between China’s Hubei (excluding Wuhan) and non-Hubei areas using data that includes case reports, human mobility, and public health interventions from 1 January to 29 February, 2020. The static and dynamic risk assessment models were developed to statistically investigate the effect trends of Hubei control strategy on case growth after adjusting importation risk and response timing with non-Hubei strategy as a contrast.
Results: The analysis detected much higher but differential importation risk in Hubei. The response timing largely coincided with the importation risk in non-Hubei areas, but Hubei areas showed an opposite pattern. A careful and comprehensive comparison showed that Hubei control strategy implemented interventions characterized by unprecedentedly strict and ‘monitored’ self-quarantine at home, while non-Hubei strategy included physical distancing measures to reduce contact among individuals within or between populations. In contrast with non-Hubei control strategy, Hubei strategy showed a much higher, non-linear and gradually diminishing protective effect with at least 3 times fewer cases.
Conclusions: A risk-based control strategy is crucial to design an effective response for COVID-19 control. Our study demonstrates that the stricter Hubei strategy can achieve much better control effectiveness. These findings highlight the health benefits of precise and differentiated strategies informed by constant monitoring of outbreak risk and policy impacts.