Abstract:

Objective To analyze the epidemiological characteristics of imported malaria cases in Fuzhou, so as to provide scientific basis for formulating prevention and control measures. Methods The data on malaria, together with the case investigation data, were collected from the Infectious Diseases Surveillance System and the Parasitic Disease Prevention and Control Information Management System under the China Disease Prevention and Control Information System reported in Fuzhou area from 2012 to 2021, and then analyzed regarding the prevalence situation, distribution in time, region and population, diagnosis of the infection at the medical institution and the time to confirm the diagnosis. Results A total of 627 overseas imported malaria cases and 2 cases imported from another province were reported in Fuzhou from 2012 to 2021. Plasmodium falciparum malaria was predominant, accounting for (n=463 cases, 73.61%), followed by Plasmodium vivax malaria (n=103 cases, 16.38%). Five hundred and fifty-six were males, and 73 females, with a male to female ratio of 7.62:1. The median age was 39 (30, 46) years, and the infection was most seen in patients aged 40-49 years (32.59%, 205/629). The imported cases occurred every month, yet were most reported in January (n=80 cases). The source of import was mainly from African countries, accounting for 89.79% (563/627), as primarily involved in Nigeria (n=80 cases), Cameroon (n=68 cases) and the Democratic Republic of the Congo (n=62 cases). The median time interval between onset and diagnosis was 3.00 (1.00, 6.00) days, and there was no statistical difference in the time interval between onset and diagnosis among years (χ²=14.047, P=0.121). The first visit at the medical institution for the reported cases mainly occurred at municipal medical institutions, which accounted for 58.03% (365/629) of the total. 73.93% (465/629) of the cases were diagnosed as malaria upon first visit, and 31.00% (195/629) of cases in re-diagnosis were inconsistent with the original diagnosis. Conclusion The population returned from the key areas in foreign countries should be strictly screened and provided with education on malaria prevention and control. In addition, the diagnosis and treatment level at grassroots medical institutions should be strengthened in order to reduce the risks of local transmission caused by imported malaria.

Key words: Malaria, Imported case, Epidemiological characteristics, Fuzhou City