关键词: 疟原虫, 来华留学生, 检测, 无症状感染者

Abstract:

Whole blood samples were collected from international students studied in China for the first time from malaria-hyperendemic regions who underwent health examinations at the Hangzhou International Travel Healthcare Center in summer and autumn during the period from 2024 to 2025, and were tested for Plasmodium using a Plasmodium antigen colloidal gold assay, blood smear microscopy, and fluorescent quantitative PCR assay (qPCR). Basic demographics and epidemiological history were collected from students tested positive for Plasmodium. A total of 530 international students from 20 countries were tested, and Plasmodium antigen colloidal gold assay tested 22 positives, with a positive rate of 4.2% (22/530), including 16 positives from Nigeria, 2 from Tanzania, 2 from Guinea, one from Democratic Republic of Congo, and one from the Republic of Congo. Among the 22 positive cases, 11 cases were positive for P. falciparum detected by qPCR, and 1 case was positive by blood smear microscopy. Epidemiological surveys revealed that all positive individuals were afebrile and asymptomatic during healthy examinations. One microscopically positive case was hospitalized for treatment, and one case was hospitalized for treatment due to fever following healthy examinations. These data indicate asymptomatic cases among international students studied in China from malaria-endemic regions. Enhanced malaria surveillance and health education is required among international students studied in China to facilitate early detection and treatment, so as to reduce the risk of overseas importation of malaria.

Key words: Plasmodium, International students in China, Detection, Asymptomatic case