Abstract:

Objective To analyze the progress of malaria elimination and epidemiological characteristics of malaria in China in 2017, in order to provide evidence-based reference for implementation of malaria elimination program. Methods The malaria epidemic data in 31 provinces/municipalities/autonomous regions(Taiwan, Hongkong and Macao regions not included) were collected through the Malaria Annual Reporting System in 2017. The epidemic situation, population distribution, species classification, regional distribution and infection sources were analyzed in Microsoft Excel 2010 software.  Results There were accumulative 2 861 malaria cases reported by 828 institutions in 2017, decreased by 13.9% compared with 2016 (3 321 cases), comprising 2 675 Chinese cases (93.5%) and 186 foreigner cases (6.5%). The male-to-female ratio was 11.4 ∶ 1. The cases were concentrated at the age range of 20-49 years (80.8%, 2 311/2 861). Nine were clinically diagnosed patients (0.3%, 9/2 861). There were 537 Plasmodium vivax cases (20.2%, 537/2 861), 1 822 P. falciparum cases(63.7%, 1 822/2 861), 67 P. malariae cases (2.3%, 64/2 861), 352 P. ovale cases (12.3%, 352/2 861), 37 cases of mixed-infection (1.3%, 37/2 861) and one P. knowlesi case. None was indigenously infected, 2 858 (99.9%, 2 858/2 861) were imported from other countries, and 3 (0.1%, 3/2 861) were infected due to transfusion. The top 5 provinces with regard to the number of malaria cases were Guangxi (13.4%, 382/2 861), Yunnan (11.4%, 325/2 861), Jiangsu (8.4%, 239/2 861), Shandong (7.3%, 209/2 861) and Sichuan (7.3%, 209/2 861). Furthermore, 136 cases(4.8%, 136/2 861) with severe clinical symptoms were reported in 18 provinces/municipalities/autonomous regions, and 7 deaths (0.2%, 7/2 861) were reported in 6 provinces/municipalities/autonomous regions. Case reportings were done within 24 h for all the cases, 83.7% (2 396/2 861) had completed case investigations within three days.  Conclusion This is the first time that no indigenous cases were reported in China in 2017. Continued efforts are needed to strengthen the monitoring and management of imported cases from abroad in some key regions to prevent malaria retransmission.

Key words:  Malaria, Epidemic status, China