Objective: This study aimed to calculate the transmissibility of coronavirus disease 2019 (COVID-19), and to evaluate the effectiveness of countermeasures to control the disease in Jilin Province, China.
Methods: The data of reported COVID-19 cases were collected, including imported and local cases from Jilin Province as of March 14, 2019. A Susceptible–Exposed–Infectious–Asymptomatic–Recovered (SEIAR) model was developed to fit the data, and the effective reproduction number (Reff) was calculated at different stages in the province. Finally, the effectiveness of the countermeasures was assessed.
Results: A total of 97 COVID-19 infections were reported in Jilin Province, among which 45 were imported infections (including one asymptomatic infection) and 52 were local infections (including three asymptomatic infections). The model fit well with the reported data (R2 = 0.593, P < 0.001). The Reff of COVID-19 before and after February 1, 2020 was 1.64 and 0.05, respectively. Without the intervention taken on February 1, 2020, the predicted cases would reach a peak of 177011 on October 22, 2020 (384 days from the first case), and 17129367 cases would be reported until the end of the outbreak (on October 9, 2021), with a total attack rate of 63.66%. These results revealed that the interventions implemented in Jilin Province had reduced more than 99.99% cases.
Conclusions: COVID-19 has a moderate transmissibility in Jilin Province, China. The interventions implemented in the province had great effectiveness.