Risks of and response to cluster outbreak of imported malaria during malaria post-elimination era in China / 中国热带医学

ABSTRACT

@#Abstract Objective　To analyze the recent cluster outbreaks of imported malaria and explore the risks, challenges and countermeasures for dealing with such events during malaria post-elimination era of malaria, and to provide reference for effectively addressing the risks and consolidating the achievements of malaria elimination. Methods　The individual malaria case data from "The Information System for Infectious Disease Surveillance" and "The Information System For Parasitic Diseases Prevention And Control" were collected，and the diagnosis classification, infection source, time and space distribution of cases were analyzed. Results　From January 1 to August 11, 2022, a total of 429 malaria cases were reported nationwide, an 18.9% decrease compared to the same period last year (529 cases), all of which were imported cases. The overall weekly trend of the outbreak remained stable, but since Week 31 (July 25-31), there has been a significant increase in the number of cases, with a peak on August 5. From July 25 to August 11, 2022, a total of 162 malaria cases were reported nationwide, up 315.4% from 39 cases in the same period last year, accounting for 37.8% of the total cases up to August 11, 2022. The main source of imported infections was Guinea (95 cases, 58.6%), with most cases reported in Longgang District, Shenzhen City, Guangdong Province (30 cases), Shilin County, Kunming City, Yunnan Province (21 cases), Chaoyang District, Beijing (11 cases), and Xiaoshan District, Hangzhou City, Zhejiang Province (7 cases). Conclusions　Due to the concentration of returnees to China, several entry port cities simultaneously experienced cluster outbreaks of imported malaria, which brought immense pressure and challenges to local medical and health institutions. Health facilities at all levels need to maintain high vigilance and sensitivity, be well prepared, and avoid death and secondary transmission caused by imported cases.