A significant association between deltamethrin resistance, Plasmodium falciparum infection and the Vgsc-1014S resistance mutation in Anopheles gambiae highlights the epidemiological importance of resistance markers

Table 1 Associations between Vgsc-L1014S genotype and three phenotypes in Anopheles gambiae s.s. from Tanzania

Phenotype	N	Vgsc-L1014S genotype			Test statistic	p value
Phenotype	N	Leu/Leu	Ser/Leu	Ser/Ser	Test statistic	p value
Deltamethrin resistant	127	31	55	41	O.R = 1.65^a	p < 0.001
Deltamethrin susceptible	399	138	190	71	χ² = 13.0^b	p = 0.002
Percentage resistant		18.1 %	22.4 %	36.6 %	χ² = 11.2^c	P < 0.001
P. falciparum positive	22	4	9	9	O.R = 2.03^a	p = 0.029
P. falciparum negative	504	165	236	103	Exact^d	p = 0.072
Percentage Pf. positive		2.4 %	3.7 %	8.0 %	χ² = 4.94^c	p = 0.026
Human positive	355	94	189	72	O.R = 1.26^a	p = 0.599
Bovine positive	17	6	8	3	Exact^d	p = 0.756
Percentage human positive		94 %	95.9 %	96.0 %	χ² = 1.60^c	p = 0.205

Leucine (Leu) is the wildtype allele and Serine (Ser) the mutated resistance associated allele
^aOdds ratio effect size was calculated based upon allelic data
^bTest statistic and p value from a χ² based on genotype frequencies
^cTest statistic and p value from a χ² test of trend
^dA Fisher’s exact test was applied as one or more expected values <5

ISSN: 1475-2875