Abstract:
Objective To investigate the epidemiological characteristics and the interval betweenonset and diagnosis of the imported Chikungunya fever cases in China from 2010 to 2019, and provide evidence for the prevention and control of Chikungunya fever.
Methods In this study, we collected the surveillance data of imported Chikungunya fever in China from 2010 to 2019, and analyze the source countries, detection ways and epidemiological characteristics of the imported cases.
Results A total of 94 imported cases of Chikungunya fever were reported in China from 2010 to 2019, in which 68 cases were reported in 2019, and 83.0% of the cases occurred during July - November. The average age of the cases was (36.4±14.2) years with a median of 35.0 years, and male to female ratio of the cases was 1.5∶1. In the imported cases, 67 (71.3%) were Chinese and 27 (28.7%) were foreigners. Yunnan, Guangdong and Zhejiang were top 3 provinces where the imported cases accounted for 37.2%, 30.0% and 10.6% of the total imported cases. Cambodia, Thailand, Bangladesh, India and Philippines were the top 5 source countries, from which 53.2%, 11.7%, 9.6%, 7.4% and 5.3% of the imported cases were reported, respectively. Thirty-eight cases (40.4%) were detected by entry quarantine, while 56 cases (59.6%) were diagnosed in medical care services after entry. The interval between onset and diagnosis was longer in the cases detected in medical care services than in the cases detected by entry quarantine (5.0±6.5) d vs. (2.8±2.5) d, t=5.090, P=0.026. There were 4 secondary outbreaks of Chikungunya fever caused by the imported cases during this period.
Conclusion The incidence of imported cases of Chikungunya fever showed increasing trend in China. It is suggested to conduct health education in international travelers, especially in Yunnan, Guangdong and Zhejiang provinces, improve the training in fever clinic staff, and strengthen entry quarantine screening in travelers from South East Asian countries in summer and autumn.