关键词: 黑箱法, 人工小时法, 蚊虫, 监测

Abstract:

Objective To compare the black box method with the labor hour method in terms of their differences in the surveillance of mosquito density and explore the possibility of substituting black box method for the labor hour method for the surveillance. Methods The differences between the black box method and the labor hour method in terms of their performance in the surveillance of mosquito density and species were compared based on the data from three independent surveillance sites, with the correlation of the two Methods in the surveillance of the species composition ratio, sex ratio and seasonal fluctuation trends examined. Results The Results showed that the density of mosquito by black box method was 1.51 mosquitoes per site, lower than that by labor hour method (3.13 mosquito per box), with a significant difference between them (t＝4.985, P＝0.0025). In terms of the seasonal fluctuation tendency of mosquitoes, similar findings from the two Methods were obtained with good correlation and significant statistical difference (r＝0.8833, P＝0.0084). It was found that the density of female mosquitoes by the labor hour method was 1.88 mosquitoes per site, higher than that by black box method (0.50 mosquito per box) with a significant difference between them (t＝5.043, P＝0.0023). There was no correlation between the fluctuation curves of the two methods(r＝0.4812, P＝0.2743). The species and composition of mosquitoes were also different with the two different methods. The main species collected by the black box method was Culex pipiens pallens(90.6%), followed by Cx.tritaeniorhynchus(4.1%), Aedes albopictus (2.4%) and Armigeres subalbatus(2.9%), with no Anopheles sinensis found. As far as the labor hour method was concerned, Cx. pipiens pallens(42.8%) and Ar. subalbatus (40.3%) were the main species collected, with Cx. tritaeriorhynchus, Ae. albopictus and An. sinensis accounting for 11.7%, 4.7% and 0.5% respectively. In addition, there was a different sex ratio of the mosquitoes collected with the two different methods, with the number of male mosquitoes larger than that of female ones in the surveillance with the black box method, and the opposite being true for the labor hour method. The quantity of female mosquitoes collected by the black box method was close to that by labor hour method, but there was a statistically significant difference (χ²＝146.18, P＜0.001). The quantity of male mosquitoes collected by the black box method was larger than that by the labor hour method with a statistically significant difference (χ²＝513.01, P＜0.0001). Conclusion The black box method, capable of capturing more female than male mosqitoes, is applicable to the surveillance of a variety of mosquito species , but the regularity and standard operating procedure (SOP) of the method as a surveillance tool remains to be studied.

Key words: Black box method, Labor hour method, Mosquito, Surveillance