domiciliary cockroaches as carriers of human intestinal parasites in lagos metropolis, southwest nigeria: implications for public health

Background: domiciliary cockroaches are obnoxious pests of significant medical importance. we investigated the prevalence of human intestinal parasites in cockroaches and its attendant public health importance. methods: overall, 749 cockroaches (periplaneta americana, 509, blattella germanica, 240) caught by trapping from 120 households comprising 3 different housing types in somolu, lagos metropolis, southwest nigeria, in 2015 were screened for human intestinal parasites using standard parasitological techniques. results: the prevalence of human intestinal parasites in cockroaches was 96.4%. there was no statistically significant difference (p> 0.05) in parasite prevalences between p. americana (95.7%) and b. germanica (97.9%). parasite species identified and their prevalence were as follows: entamoeba histolytica/dispar (44.1%), e. coli (37.8%), giardia lamblia (18.7%), cryptosporidium sp. (13.8%), ascaris lumbricoides (61.3%), trichuris trichiura (55.8%), hookworms (11.6%), strongyloides stercoralis (11.7%), taenia/echinococcus spp. (10.5%), enterobius vermicularis (17.2%) and hymenolepis nana (11.6%). parasite prevalence and burdens varied with housing type; the prevalence was significantly higher statistically (p< 0.05) in cockroaches from low-cost bungalow, lcb (100%) and low-cost, 2-storey, lc2-s (100%) houses than in medium-cost flats, mcf (81.3%). parasite burdens were also significantly higher statistically (p< 0.05) in cockroaches from lcb or lc2-s than in cockroaches from mcf. parasite prevalences between cockroach gut and body surfaces were not statistically significant (p> 0.05) but mean parasite burdens in gut were significantly higher statistically (p< 0.05) than on body surfaces. conclusion: cockroaches types carry transmissive stages of human intestinal parasites and may act as reservoirs and potential mechanical vectors for disease transmission.