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Objective: To understand the control status of malaria at hotspots in Yingjiang County and provide measures for malaria elimination in the China-Myanmar border areas of Yunnan Province., Methods: A survey was made in 4 villages with indigenous malaria cases or imported cases in Nabang and Tongbiguan of Yingjiang County in Yunnan Province in June and July 2015. Peripheral blood samples were collected from the neighboring residents around patients and examined by malaria rapid diagnostic test （RDT）. The results were further verified by nested-PCR. Mosquitoes were collected by overnight trapping with light traps in Jingpo, Lilisu, Jiema, and Mengxiangyang villages or by human landing catches in Jingpo and Lisu villages. Nested-PCR was performed on part of the captured Anopheles minimus to detect the malaria parasites., Results: One hundred and ninety-four filter blood samples were collected from 11 malaria cases in two sites. All were detected to be negative for Plasmodium by RDT. In contrast, two samples originated from Jingpo and Lisu villages with indigenous cases were detected to be positive for Plasmodium vivax by nested-PCR. A total of 2 374 mosquitoes were captured, belonging to 22 species of 4 genera: Anopheles, Culex, Aedes and Armigeres. The mosquitoes were predominated by genus Culex, followed by genus Anopheles（11.33%, 269/2 374） which was dominated by A. minimus（49.07%, 132/269）, then was A. sinensis（4.09%, 11/269）, A. maculatus（2.23%, 6/269）, A. jeyporiensis（0.74%, 2/269）and so on. The mean indoor man-biting rate of mosquitoes was 5.78 and 3.20 per person per hour for Jingpo and Lisu villages, and the mean outdoor man-biting rate of mosquitoes was 2.30 per person per hour for Lisu Village. The 14 A. minimus were negative for sporozoite infection as detected by nested-PCR., Conclusion: Nested-PCR showed that there are asymptomatic Plasmodium carriers in Yingjiang’s border area of Yunnan Province. Four major mosquito species as malaria vectors exist with A. minimus as the dominant one.

The malaria epidemics in Laza city of Myanmar and Yingjiang county in Yunnan province of China in 2012 and 2013 was reviewed retrospectively, and a survey on malaria infection was conducted in residents in the border areas. A total of 179 malaria cases were reported in Yingjiang county from 2012 to 2013, with an average annual incidence of 2.9 per 10,000. Of the 179 cases, 77.7% were imported cases and 22.3% were local cases; 79.3% were infected with Plasmodium vivax, 20.1% with P. falciparum, and 0.6% unidentified. In Laza city of Myanmar, 2,069 malaria cases were reported, with an average annual incidence of 322.5 per 10,000. Of them, 73.4% cases were infected with P. vivax, 20.1% with P. falciparum and 6.5% unidentified. In addition, the microscopic results revealed that the malaria parasite rate in the residents in Yingjiang county was 0%, while that in Laza city was 1.5%.