Effects of Chinese Strategies for Controlling the Growth Speed of the Cumulative Confirmed Cases of Novel Coronavirus–Infected Pneumonia in China

Background: In December 2019, an outbreak of new type of coronavirus named COVID-19 occurred in Wuhan, Hubei Province, China. In a very short time, this virus spread rapidly over China, greatly threatening public health and economic development. The Chinese government acted quickly and implemented a series of strategies to prevent diffusion of this disease. We therefore sought to evaluate the effects of these Chinese strategies for controlling the spread of COVID-19. Methods: From the data of cumulative confirmed cases from provincial Health Commission websites of China, we performed the phenomenological model to estimate known data by nonlinear least squares regression and calculated the growth speed of cumulative confirmed patients. We further analyzed the time when this growth speed, the rate of the number of new cases, reached its maximum (Speedmax). Comparing different times to Speedmax of different areas in China, we calculated the dates at which the growth speed began to decline in different areas. Also, the number of plateaus were analyzed. Results: The quartic model showed the best fit. For almost all areas in mainland China, the speed of infections reached Speedmax and began to decline within 14 days; exceptions were Hebei, Heilongjiang, Hainan, Guizhou, and Hubei. The number of plateaus was significantly correlated with the emigration index. However, the distance from other areas to Hubei and the number of plateaus had little influence on when a province or area arrived at Speedmax. Once strict intervention strategies were implemented, diffusion and deterioration of COVID-19 were inhibited quickly and effectively over China. Conclusion: Our study suggests that Chinese strategies are highly effective on controlling the diffusion and deterioration of the novel coronavirus–infected pneumonia. These strategies supply experience and guidelines for other countries to control the COVID-19 epidemic. Funding Statement: None. Declaration of Interests: The authors declare no conflicts of interest. Ethics Approval Statement: Publicly available data.