Molecular Detection of Benzimidazole Resistance Genes and Associated Risk Factors in Hookworms from HIV-positive and HIV-negative Patients in Plateau State, Nigeria

An individual may be predisposed to infection with hookworms through various activities that bring them into contact with filariform larvae in soil. Parasite control programs that rely on mass drug administration (MDA) over prolonged periods using the same antihelmintic drugs would exert selection pressure on hookworm populations and favour the development of drug resistance. This cross-sectional study was conducted to detect benzimidazole resistance genes and assess risk factors of hookworm infection among HIV-positive and HIV-negative patients in Plateau State, Nigeria. A total of 526 stool samples were collected and analysed for hookworm eggs using wet mount and formol-ether concentration techniques. Specimens confirmed to be hookworm-positive by microscopy were further subjected to molecular analyses on Real-Time qPCR. A well-structured questionnaire was administered to each participant to obtain information on risk factors. The result showed an overall prevalence of 6.46%; with 3.62% and 10.36% for HIV-positive and HIV-negative patients, respectively. Subjects who arrived at their farms before sunrise recorded higher hookworm prevalence (9.63%) compared to those who arrived at their farms after sunrise (2.30%). Also, subjects who conduct farm activities barefoot had a higher hookworm prevalence (7.99%), while those who wear footwear had a lower prevalence (3.07%). Again, subjects who had never been dewormed had a higher hookworm prevalence (20.93%); while those who were dewormed less than 6 months ago had a lower prevalence (1.85%). A statistically significant association was found to exist between hookworm infection and these risk factors at P ≤ 0.05. Out of the 34 samples positive by microscopy for hookworms, 16 were confirmed to be Necator americanus on qPCR. However, 5 out of the 16 samples were from HIV-positive patients, while 11 were from HIV-negative patients. Single-nucleotide polymorphisms (SNPs) were detected in 2 samples on codons 167 and 200. The occurrence of these SNPs was found only among HIV-negative patients. In conclusion, the detection of SNPs suggests that mutant genes associated with benzimidazole resistance are circulating in hookworms in Plateau State, Nigeria.