Molecular Characterization of Hookworm Detected among Peasant Farmers and their Haemoglobin Profile in selected Local Government Areas of Kaduna State, Nigeria.

Abstract

This study aimed at determining the prevalence of hookworm infection among peasant farmers in selected Local Government Areas (LGAs) of Kaduna State, Nigeria. A cross-sectional, descriptive study was carried out between November 2014 and October 2015. One thousand two hundred eligible peasant farmers were enrolled in the study. One LGAwas selected from each of the three Senatorial Zones of Kaduna State by simple random sampling method. Samples were analysed for the presence of hookworm ova using direct wet mount and formal-ether concentration technique as well as determine the haemoglobin profile and characterize the hookworm species. The haemoglobin profile of the peasant farmers in relation to hookworm infection was determined using Mission Haemoglometer Stirps Test Kits. The stool samples that were highly positive microscopically for hookworm ova were selected for molecular analysis, 5 from each LGA, making a total of 15 samples. The stool samples were subjected to DNAextraction, DNAconcentration/Purity estimation, PCR, Agarose gel electrophoresis, Sequencing, BLAST and Phylogenetic analysis of the isolates were carried out. The results obtained showed the overall prevalence of hookworm infection in the study population to be 18.7%. In respect to LGA, the prevalence of hookworm infection was 24.0% in Jema'a, 17.3% in Chikun and 14.8% in Zaria LGA. The prevalence of hookworm infection was found to be significantly associated in the studied LGAs (P< 0.002). The distribution of hookworm infection in relation to Haemoglobin (Hb) level revealed that, the farmers with the Hb/PCV level of 6-10/18-30% had the highest prevalence of 43.0% (128/298) while farmers with Hb/PCV of 16-20/48- 60% had the lowest prevalence of 3.7% (1/27) and a statistically significant difference of P=0.000. The electrophoresis of 15 amplicons obtained from 15 positive stool samples from the three selected LGAs showed a corresponding base pair band of 310bp which corresponds with the base pair of the N. americanus positive control. The sequencing and basic local alignment search tool (BLAST) revealed that Sequence of Sample No. 5 from Zaria LGA had 95% identity with that of N. americanus, sequence of Sample No. 10 from Chikun LGAhad 99% identity with that of N. americanus and finally sequence of Sample No.15 from Jema'a LGAalso gave a similar correlation of 97% as that of N. americanus. The result of the species-specific identification of the two human hookworm species (i.e. N. americanus and A. duodenale) obtained shows that N. americanus was predominant in the study area (Kaduna State, Nigeria) during the study. The results of this study indicated an overall prevalence rate of hookworm infection of 18.7% among peasant farmers in Kaduna State. This indicates a potential risk of severe anaemia among individuals particularly the vulnerable groups such as pregnant women and children of school age who participate in farming. In conclusion, this study revealed the transmission of human hookworm among peasant farmers in Kaduna State to be at an alarming rate. Thus, major prevention and control measures should be adopted to avoid further spread of the infection; and more so, there is a need for prompt treatment of the infected persons as well as creating a law that will prohibit indiscriminate defeacation on farmlands.