Investigation of plague foci in Cangyuan County, Yunnan Province, China-Myanmar border region in 2023
- Author:
LI Siyu
;
SHAO Zongti
;
LIU Zhengxiang
- Publication Type:Journal Article
- Keywords:
Plague;
focus investigation;
China-Myanmar border region;
Cangyuan County
- From:
China Tropical Medicine
2025;25(2):136-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To understand the situation of plague host vectors, indicator animals and residents infected with plague bacteria in Cangyuan County, Yunnan Province, China-Myanmar border region, and to explore the risk of plague epidemic, so as to provide reference basis for supplementary plague data and prevention and control in this area. Methods A plague survey was carried out in three townships in Cangyuan County in 2023. The collected host animals organs and body surface parasitic fleas were bacterial cultured. Serum collected from border residents, indicator animals, and host animals was tested for plague F1 antibodies using indirect hemagglutination assay (IHA). The positive samples were rejudged by IHA, immune colloidal gold assay(GICA) and up-converting phosphor technology(UPT). Results Totally 294 serum samples were collected from border residents, with an average age of (48.48±14.27) years old, with more females than males. Three were positive for F1 antibody against Yersinia pestis, with a positive rate of 1.02%. And 65 samples of indicator animal serum and 31 samples of Rattus tanezumi serum were collected, and the detection of plague F1 antibody was negative. And 198 rodents belonging to 3 orders, 5 families, 11 genus and 14 species were captured, with a total capture rate of 7.93%, with Rattus tanezumi (46.97%) and Rattus andamanensis (19.19%) as the dominant species. The capture rate in residential indoor areas was 3.72%, and Rattus tanezumi was the absolutely dominant species (100.00%). The capture rate in farming areas was 10.26%, the dominant species were Rattus tanezumi (36.36%), Rattus andamanensis (23.03%), Mus pahari (10.30%) and Hylomys suillus (10.30%). And 60 fleas belonging to 3 families, 5 genera and 6 species were seized, the average infection rate of fleas was 11.62%, and the total flea index was 0.30. The dominant species were Xenopsylla cheopis (28.34%), Palaeopsylla remota (23.33%), Ctenophthalmus quadratus (18.33%), Stivalius aporus (15.00%) and Palaeopsylla incurua (11.67%). A total of 198 murine organ samples were isolated and cultured, and 24 groups of flea samples were obtained, no Yersinia pestis was isolated. Conclusion The investigation has not found any recent infection with Yersinia pestis in rodents, body surface parasitic fleas and indicator animals; however, it is found that there is still a certain proportion of positive population of plague F1 antibody in the serum of residents. Rattus tanezumi and Xenopsylla cheopis are the first dominant species of host and vector in the county, the indoor density of Rattus flavipectus exceeds 3%, reaching the animal pestis IV early warning, and there is a risk of recurrence in the plague foci.
- Full text:20251114102256023982.Investigation of plague foci in Cangyuan County, Yunnan Province, China-Myanmar border region in 2023.pdf