A Survey of External and Gut Bacterial Isolates of American Cockroach (Periplanetaamericana) Collectedfrom University of Lagos, Akoka Campus, Lagos State, Nigeria

Document Type : Original Article

Authors

1 Applied Entomology Unit, Zoology Department, University of Lagos Nigeria.

2 Vector Control Laboratory, Public Health Department, Nigerian Institute of Medical Research, Yaba Lagos Nigeria.

Abstract

The American cockroach, Periplaneta americana (Linnaeus, 1758; Blattoidea; Blattidae) has become synonymous with human dwellings, as inevitable pest organisms constituting nuisance and transmitting disease organisms of public health significance. This study investigated the morphometric analysis of cockroaches within the University of Lagos, Akoka campus as well as the array of pathogenic bacterial organisms they harbour. A total of one hundred and fifty cockroach individuals were collected from within and around Faculty of Science, Faculty of Engineering, and DLI. They were transported to the laboratory for morphometric analysis using standard measurements. Microbial isolation/identification was carried out through swabs on external surfaces and dissection for gut isolates. Morphometric analysis showed that cockroaches from Faculty of Science had the highest mean total length (9.95±0.14 cm), and those of DLI had the lowest mean total length (9.50±0.14 cm), although no significant difference was observed for the three locations (p>0.05). A total of eleven pathogenic bacteria species were isolated and identified. They include Staphylococcus aureus (16.6%), Bacillus cereus (16.6%), Salmonella typhimurium (13.3%), Escherichia coli (13.3%), Proteus mirabilis (8.3%), Enterobacter aerogenes (6.6%), Pseudomonas aeruginosa (3.3%), Pseudomonas putida (3.3%), Klebsiella spp.(3.3%), Citrobacter spp (3.3%) and Bacillus megaterium (3.3%). The presence of these pathogens on the surfaces and in the gut of the sampled cockroach populations suggested their implication in the transmission of diseases among the human residents. Hence, a careful consideration of cockroach distribution, microbial load and attendant public health concerns should be routinely conducted in order to determine and implement sustainable control strategies within the campus environment.

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