Seroprevalence of Toxocara canis and the parasitic effect on plasma cytokines in children aged 6 to 11 years in Saki-East local government area in Nigeria

Study Background: Toxocara canis is a helminths parasite known as dog worm but infects human through infected dog feces or contaminated dirt. It is a neglected disease in economically less privileged areas. The parasitic infection can generate inflammatory process. Aim and Objective: This work was designed to determine the seroprevalence of T. canis and the parasitic effect on plasma cytokines in children aged 6–11 years in Saki-East local government area in Nigeria. Materials and Methods: Two hundred children aged 6–11 years (female – 100 and male – 100) were recruited across Saki-East local government area. One hundred and sixty-one of them not infected with any of the infectious agents were studied as control. Sputum, blood, stool, skin snip, and urine samples were obtained for microscopic identification of parasites. Sputum sample was also used for Ziehl–Neelsen staining to demonstrate acid-fast bacilli, while ELISA technique was used for determination of T. canis, anti-hepatitis C virus (HCV), HBsAg, HIV1-p24 antigen, tumor necrosis factor-alpha (TNFα), and interleukin (IL)-10. Results: The results obtained showed overall seroprevalence of T. canis among the children as 9.5% (19) including 6% (12) male and 3.5% (7) female children. This included 5.5% (11) monoinfected with T. canis; 1% (2) were T. canis coinfected with Ascaris lumbricoides; 1% (2) were T. canis coinfected with hepatitis B virus; 1% (2) were T. canis coinfected with Plasmodium spp.; 0.5% (1) were T. canis coinfected with hookworm; and 0.5% (1) were T. canis coinfected with Schistosoma haematobium. There is no coinfection with either HIV or HCV among the children. 10% (20) were infected with infectious agents but seronegative to T. canis. There was a significant increase in the plasma values of cytokines TNFα and IL-10 in T. canis monoinfected children compared with the control (P < 0.05). Conclusion: The work revealed an overall seroprevalence of T. canis as 9.5% including 5.5% monoinfection and a significant increase in plasma TNFα and IL-10 in T. canis monoinfection.