Prevalence of cockroaches (Periplanata americana) in households in Calabar: Public health implications

Abstract

The study was carried out in Anantigha area of Calabar, Nigeria and involved the trapping and examination of cockroaches from toilets, kitchens, living rooms and bedrooms of houses to determine the parasites in and on the cockroaches and also to assess the possible role of the cockroaches in the dissemination of medically important parasites. A total of 322 cockroaches were trapped from the different sites within the households and all identified as Periplananta americana species. Out of the 322 cockroaches examined, 58.6% were infected with one or several species of gastrointestinal parasites. Parasites isolated and identified include Balantidium coli (8.8%), Hookworms (9.6%), Entameba coli(10.4%), Enterobius vermicularis (12. 9%), Entameba histolytica (13.7%), Trichuris trichuira(16.9%) and Ascaris lumbricoides (24.4%). Cockroaches collected from the toilets had the highest parasite load of 4 to 54 parasites/ml followed by those from the kitchen with 1 to 24 parasites/ml, and those from the living room 1 to 12 parasites/ml while 1 to 10 parasites/ml was observed from cockroaches from the bedroom. No cestodes were encountered in this study. More parasites were recovered from the external than in the gastro-intestinal tract with prevalence rates of 65.3 and 34. 6%, respectively. The presence of gastro-intestinal parasites was significant since these parasites can easily be transferred by the cockroaches to humans. This study has shown that cockroaches represent an important reservoir of important parasites which can cause disease in man. It also highlights the potential of cockroaches as mechanical transmitters of parasite ova and cysts which they pick up from faeces and transfer to food by crawling. There is need to control cockroaches indoors and outside. Key words: Cockroaches, parasites, mechanical transmission, Calabar, Nigeria.