Pyrethroid resistance status and co-occurrence of V1016G, F1534C and S989P mutations in the Aedes aegypti population from two dengue outbreak counties along the China-Myanmar border

Table 1 The resistance status of Aedes aegypti from Ruili and Gengma counties to the three tested insecticides

Pesticides (concentration)	Sampling point	Number of mosquitoes tested	Number of knockdowns in 1 h (N mosquitoes)	Knockdown rate (%)	Statistical analysis	KDT₅₀, in minutes (95% CI)	Number of deaths (N mosquitoes)	24-Hour mortality rate (%)	Resistance status^a	Statistical analysis
Permethrin (3.20%)	Ruili	72	23	31.9	χ² = 0.079, df = 1, P = 3.086	70.277 (63.133–86.847)	13	18.06	R	χ² = 0.311, df = 1, P = 0.577
Permethrin (3.20%)	Gengma	64	12	18.8	χ² = 0.079, df = 1, P = 3.086	409.184 (151.079–19555.008)	14	21.88	R	χ² = 0.311, df = 1, P = 0.577
Lambda-cyhalothrin (0.08%)	Ruili	70	29	41.4	χ² = 2.385, df = 1, P = 0.122	64.950 (59.577–75.552)	8	11.43	R	χ² = 12.926, df = 1, P = 0.000*
Lambda-cyhalothrin (0.08%)	Gengma	97	29	29.9	χ² = 2.385, df = 1, P = 0.122	100.955 (79.627–149.577)	35	36.08	R	χ² = 12.926, df = 1, P = 0.000*
Deltamethrin (0.20%)	Ruili	75	51	68.0	χ² = 1.312, df = 1, P = 0.252	47.100 (43.892–51.117)	18	24.0	R	χ² = 118.402, df = 1, P = 0.000*
Deltamethrin (0.20%)	Gengma	107	81	75.7	χ² = 1.312, df = 1, P = 0.252	37.841 (34.874.-41.311)	107	100.0	S	χ² = 118.402, df = 1, P = 0.000*
Control	Ruili	25	0	0	–^b	/^c	0	0	/	–
Control	Gengma	25	0	0	–^b	/	0	0	/	–

CI Confidence interval KDT₅₀ Time (in minutes) taken for 50% of the test mosquitoes to be knocked down,
*Statistical significant difference at P < 0.05
^aS indicates susceptible, based on a mortality rate of ≥ 98%; R indicates resistant, based on a mortality rate < 90%
^b–, Not determined
^c/, No results

ISSN: 1756-3305