[Epidemiological characteristics of imported malaria cases in Guangxi Zhuang Autonomous Region from 2017 to 2024]

To analyze the epidemiological characteristics of imported malaria cases in Guangxi Zhuang Autonomous Region from 2017 to 2024, so as to formulate the targeted control strategies for imported malaria.

The demographic and epidemiological data of malaria cases reported in Guangxi Zhuang Autonomous Region from 2017 to 2024 were collected through the China Disease Prevention and Control Information System. The source of malaria cases acquiring infections, composition of malaria parasite species, regional distribution of malaria cases, population characteristics of malaria cases, temporal distribution of malaria cases, time of diagnosis, deaths and institutions reporting malaria cases were statistically analyzed with a descriptive statistical method.

A total of 1 308 malaria cases were reported in Guangxi Zhuang Autonomous Region from 2017 to 2024, and all cases were overseas imported cases, with no secondary cases identified. Plasmodium falciparum malaria (57.11%, 747/1 308) and P. ovale malaria (27.68%, 362/1 308) were two most common forms of malaria, and three deaths occurred among P. falciparum malaria cases. The number of malaria cases appeared an overall tendency towards a decline from 2017 to 2022, followed by a rise after 2023. The malaria cases predominantly acquired infections from Africa (1 284 cases, accounting for 98.17%), with Ghana (432 cases, accounting for 33.03%) and Cameroon (145 cases, accounting for 11.09%) as two most frequent origin countries, and P. falciparum malaria (58.02%, 745/1 284) was the predominant form of malaria among African imported malaria cases; however, P. vivax malaria cases comprised 89.58% (86/96) of all malaria cases derived from Ethiopia. In terms of regional distribution, malaria cases were highly concentrated in Nanning City (1 075 cases, accounting for 82.19%), with the most prominent situated in Shanglin County (903 cases, accounting for 69.04%), and these cases were predominantly found among individuals at ages of 20 to 59 years (1 280 cases, accounting for 97.86%), males (1 265 cases, accounting for 96.71%), and gold/coal mining workers (1 042 cases, accounting for 79.66%). In terms of temporal distribution, malaria cases were reported throughout the year, with the peak incidence in April (146 cases, accounting for 11.16%). The median duration from onset of disease to initial diagnosis was 1 (interquartile range, 2) day, and the median duration from initial diagnosis to definitive diagnosis was 1 (interquartile range, 1) day. Malaria cases were predominantly reported by medical institutions (1 075 cases, accounting for 82.19%), and the proportion of malaria cases reported by medical institutions increased from 75.92% in 2017 to 96.27% in 2024, while the proportion of malaria cases reported by disease control and prevention institutions reduced from 24.08% in 2017 to 3.73% in 2024. There was a significant difference in the proportion of malaria cases reported by medical institutions and disease control and prevention institutions from 2017 to 2024 (both P < 0.001). The 3 dead imported P. falciparum malaria cases predominantly received initial diagnosis at townshipand lower-level institutions (66.67%, 2/3), with 1 (interquartile range, 2) day median duration from onset of disease to initial diagnosis, 2 (interquartile range, 4) days median duration from initial diagnosis to definitive diagnosis, and 1 (interquartile range, 19) day median duration from definitive diagnosis to death.

Imported P. falciparum malaria from Africa is predominant among malaria cases in Guangxi Zhuang Autonomous Region, and malaria cases are highly concentrated in specific regions and among specific occupational groups. It is recommended to strengthen inter-departmental collaboration, implement refined management among labors going to Africa, improve the integration of medical treatment and disease prevention, and enhance the diagnosis and treatment of severe malaria cases.