Epidemiological Characteristics of COVID-19 under Government-mandated Control Measures in Inner Mongolia, China

Abstract BackgroundThere were 75 local confirmed cases during the COVID-19 epidemic followed by an outbreak of Wuhan in Inner Mongolia. The aims of our study were to provide reference to control measures of COVID-19 and scientific information for supporting government decision-making for serious infectious disease, in remote regions with relatively insufficient medical resources like Inner Mongolia.MethodsThe data published by Internet were summarized in order to describe the epidemiological and clinical characteristics of patients with COVID-19. The basic reproductive number (R 0 ), incubation period, time from illness onset to confirmed and the duration of hospitalization were analyzed. The composition of imported and local secondary cases and the mild/common and severe/critical cases among different ages, genders and major clinical symptoms were compared.ResultsIn 2020, from January 23 to February 19 (less than 1 month), 75 local cases of COVID-19 were confirmed in Inner Mongolia. Among them, the median age was 45 years old (34.0, 57.0), and 61.1% were male and 33 were imported (44.0%). 29 (38.7%) were detected through close contact tracking, more than 80.0% were mild/common cases. The fatality rate was 1.3% and the basic reproductive number (R 0 ) was estimated to be 2.3. The median incubation period was 8.5 days (6.0~12.0) and the maximum incubation period reached 28 days. There was a statistically difference in the incubation period between imported and local secondary cases ( P <0.001). The duration of hospitalization of patients with incubation period <8.5 days was higher than that of patients with incubation period ≥8.5 days (30.0 vs. 24.0 days).ConclusionIn Inner Mongolia, an early and mandatory control strategy by government associated with the rapidly reduced incidence of COVID-19, by which the epidemic growth was controlled completely. And the fatality rate of COVID-19 was relatively low.