The burden of Vector-Borne and Soil-Transmitted Polyparasitism in a Nigerian Rural Community: A cross-sectional study

Background: Concomitant parasitic infections are common in the developing world, yet most studies focused on a single parasite in a narrow age group. This study investigated the extent of polyparasitism and co-infections in a rural community in Osun State, Nigeria. Methods: Two hundred and forty-seven consenting individuals consisting of 118 males and 129 females participated in this study. Faecal specimens, venous blood, and skin snips were collected from the participants. The Kato-Katz technique was used to screen the faecal samples for soil-transmitted helminth, while Giemsa-stained blood smears were used for Plasmodium falciparum detection. Skin snips microscopy and haematoxylin-stained blood smears were used to diagnose onchocerciasis and loiasis, respectively. Demographic information was collected from all the participants. Results: The prevalence of P. falciparum, hookworms and Ascaris lumbricoides were 55.9%, 19.4% and 26.3%, respectively. The overall prevalence of the filarial infections was 4.5% for Loa loa microfilaremia, 23.5% for Onchocerca volvulus microfilarial. Thirty-eight per cent of the population harboured at least two parasites concurrently. Females (52.2%) were generally more infected with all the helminths than males (48.8%), but the difference was not statistically significant (p=0.128). For onchocerciasis prevalence, males (29.7%) were more infected than females (17.8%), and the difference was statistically significant (p=0.035). Co-infection of malaria and loiasis was observed in 1.2% of the population (p=0.051), while 13% were co-infected with malaria and onchocerciasis (p=0.903). Co-infection of malaria and hookworm was observed in 10.5% of the population. The overall mean Packed Cell Volume (PCV) of the population was 40.03±5.84, and no significant difference (p=0.224) was observed between PCV and infection status. Also, no significant association (p=0.051) was observed between the age group and infection status. The intensity of the parasites was classified into 1-9, 10-99, 100-149, and 150 and above. Almost all the helminths except Ascaris lumbricoides had a low grade of helminths (1-9). The intensity was more pronounced in Ascaris lumbricoides than in other helminths. A. lumbricoides + P. falciparum co-infection had a higher geometric mean para-sites density (GMPD) value when compared with only P. falciparum infection. There was no significant difference in co-infection of P. falciparum + loa loa, P. falciparum + O .volvulus and P. falciparum + Hookworm with P. falciparum alone. Conclusion: This study confirmed that polyparasitism is still common in rural communities in the study area. The findings can be used to design and implement appropriate intervention strategies to alleviate morbidity and co-morbidity in rural communities.