关键词: 疟疾, 疟原虫, 输入性, 成都口岸

Abstract:

Malaria surveillance data were collected from individuals entering China via Chengdu Port of Entry from 2024 to 2025, and the temporal, regional and population distributions of malaria were analyzed using a descriptive epidemiological method. A total of 11 144 traveler received malaria tests during the study period from 2024 to 2025, and the overall prevalence of malaria parasite infections was 1.55% (173/11 144). Among the confirmed infections, Plasmodium falciparum accounted for 94.22% (163/173), followed by P. malariae 3.68% (6/173), P. ovale 1.16% (2/173) and P. vivax 1.16% (2/173). The detection of malaria parasites was higher in 2025 (2.86%, 139/4 865) than in 2024 (0.54%, 34/6 279) (χ² = 96.78, P < 0.01). In terms of temporal distribution, the highest number of Plasmodium infections (87 cases, 50.29%) was reported during the period from October to December, followed by between July and September (56 cases, 32.37%). In terms of country of origin, most cases entered China from Ethiopia (87.86%, 152/173), followed by Qatar (5.20%, 9/173). In terms of case identification, most cases (70.52%, 122/173) were detected via on-site medical inspection, followed by high fever alerts (21.39%, 37/173). Of the 173 Plasmodium-positive cases, 166 were male (95.95%) and 7 were female (4.05%), with a male-to-female ratio of 23.71: 1. The majority of infected individuals were aged 31 to 60 years (85.55%, 148/173), with the largest number of cases detected at ages of 31 to 40 years (32.37%, 56/173). In terms of occupation, migrant labors constituted the largest proportion (89.02%, 154/173), followed by business (4.62%, 8/173). Among Plasmodium-positive individuals, 5 cases (14.70%, 5/34) in 2024 and 80 cases (57.55%, 80/139) in 2025 had a previous history of malaria. There were 71 cases (41.04%, 71/173) with fever upon entry. Laboratory screening under the multi-disease prevention strategy revealed 13 cases (7.51%, 13/173) co-infected with malaria and sexually transmitted diseases, and 29 cases (16.76%, 29/173) co-infected with respiratory infectious diseases. Malaria infections present distinct temporal, population and geographical characteristics among individuals entering China via Chengdu Port of Entry, and the risk of malaria infections rose markedly in 2025.

Key words: Malaria, Plasmodium, Imported, Chengdu Port