Early Epidemiological Features and Trends of the COVID-19 Outbreak in Southeast Asia: a Population-Level Observational Study

Background: The global outbreak of coronavirus disease 2019 (COVID-19) has been ongoing in Southeast Asia since 13 January 2020. To guide intervention strategies and summarize beneficial experience, we describe the early epidemiological features and evaluate the trends of the COVID-19 outbreak in Southeast Asia. Methods: In this population-level observational study, we compiled a list of individual patients with COVID-19 and daily country-level case counts between 13 January 2020 and 16 March 2020 in Southeast Asia. Relevant spatiotemporal distributions, demographic characteristics and short-term trends were assessed. Results: A total of 1,346 confirmed cases of COVID-19 with 217 (16.1%) recoveries and 18 (1.3%) deaths were reported in Southeast Asia as of 16 March 2020. The early transmission dynamics was fit with an exponential regression model: y=0.30e0.13x (p<0·01, adjusted R2 = 0.96). Using this model, we predicted that the cumulative number of reported COVID-19 cases in Southeast Asia would exceed 10,000 by early April 2020. A total of 74 cities across 8 countries in Southeast Asia were affected by COVID-19 and most of the confirmed cases were located in 5 international metropolitan areas. Demographic analysis conducted on 925 confirmed cases indicated a median age of 44 years and a sex ratio of 1.25. Median age of local patient population was significantly higher than that of general population in corresponding country (p<0·01), whereas sex ratio did not significantly differ. Conclusions: The situation of COVID-19 endemic in Southeast Asia is intricate and not optimistic in the short-term. Dynamic disease surveillance and targeted intervention strategies are urgent.