Correlation between the migration scale index and the number of new confirmed Novel Coronavirus Pneumonia cases in China
Abstract Background: In late December, 2019, patients of atypical pneumonia due to an unidentified microbial agent were reported in Wuhan, Hubei Province, China. Subsequently, a novel coronavirus was identified as the causative pathogen which was named 2019 novel coronavirus (2019-nCoV). As of Feb 12, 2020, more than 44,000 cases of 2019-nCoV infection have been confirmed in China and continue to expand. Provinces, municipalities and autonomous regions of China have launched first-level response to major public health emergencies one after another from Jan 23.2020, which means restricting movement of people among provinces, municipalities and autonomous regions. The aim of this study was to explore the correlation between the migration scale index and the number of confirmed Novel Coronavirus Pneumonia (NCP) cases and to depict the effect of restricting population movement. Methods: Excel 2010 was used to demonstrate the temporal distribution at the day level and SPSS 23.0 was used to analyze the correlation between the migration scale index and the number of confirmed NCP cases. Results: Since January 23, 2020, Wuhan migration scale index has dropped significantly and since January 26, 2020, Hubei province migration scale index has dropped significantly. New confirmed NCP cases per day in China except Wuhan gradually increased since January 24, 2020, and showed a downward trend from February 6, 2020. New confirmed NCP cases per day in China except Hubei province gradually increased since January 24, 2020, and maintained at a high level from January 24, 2020 to February 4, 2020, then showed a downward trend. Wuhan emigration scale index from January 9 to January 22, January 10 to January 23 and January 11 to January 24 was correlated with the number of new confirmed NCP cases per day in China except Wuhan from January 22 to February 4. Hubei province emigration scale index from January 10 to January 23 and January 11 to January 24 was correlated with the number of new confirmed NCP cases per day in China except Hubei province from January 22 to February 4.Conclusions: People who left Wuhan from January 9 to January 22 may lead to the outbreak in China except Wuhan and people who left Hubei province from January 10 to January 24 may lead to the outbreak in China except Hubei province. “Wuhan lockdown” and Hubei province launching first-level response to major public health emergencies may have had a good effect the control NCP epidemic. Because there were still new confirmed NCP cases in China except Wuhan and in China except Hubei province and this may indicate that the occurrence of second-generation cases.