Microbiological studies of cockroaches from three localities in Gaborone, Botswana

Abstract

Cockroaches have become the most common pests in a majority of households in Gaborone, the capital city of Botswana Their presence has always raised safety concerns, especially as carriers of food-borne pathogens and food-spoilage organisms. To address the safety issues, bacteriological investigations were carried out on cockroaches trapped from the kitchens and toilets of three localities in Gaborone, households in Botswana. The bacterial, total spore forming, Bacillus cereus, coliforms and E. coli counts from the surfaces of cockroaches were estimated using bacteriological media. Aerobic and facultatively anaerobic bacteria from the fecal pellets were isolated and characterized. Specialized media were used for culturing pathogens. 67 %, 22.2 % and 28.6 % of the cockroaches trapped in the kitchen from Central/Broadhurst, Old Naledi and Tlokweng, respectively, had aerobic plate counts of > 10 6 CFU/cockroach. The cockroaches trapped from the toilets had higher counts than kitchens. Sporeformers were present in most samples though in lower numbers. However, Bacillus cereus was only found in some of the cockroaches at much lower numbers. As much as 70-98.3% of the cockroaches had coliforms; but, E. coli was only found in 5-6.5% of the cockroaches at > 10 3 CFU/cockroach. 70 species of bacteria representing 37 genera were isolated from the surface and fecal pellets. Even though the majority of the bacteria that were isolated from the surfaces were Gram negative those from the pellets were mostly Gram positive. The most common and abundant species belonged to Pseudomonas and Serratia, with members of the Enterobacteriaceae following. In the pellets, species of Bacillus were predominant, but, there were some members of Enterobacteriaceae. Pathogens like Salmonella, Shigella and B. cereus were isolated. Opportunistic pathogens like species of Pseudomonas, Klebsiella and Vibrio and food spoilage bacteria such as species of Enterobacter, Citrobacter, Escherichia, Erwinia, and Pseudomonas were also found. Proper care in disposal of food remnants and overall cleanliness at the households prevents cockroaches from foraging in the kitchen and toilet. Une attention particulière devra être prêtée à la disposition des restes alimentaires ainsi qu'à la propreté générale des ménages afin de prévenir la fouille des cancrelats dans les cuisines et toilettes.

Vector Potential ofBlattella germanica(L.) (Dictyoptera: Blattidae) for Medically Important Bacteria at Food Handling Establishments in Jimma Town, Southwest Ethiopia

“…The S. flexneri isolate detected from cockroaches body substantiated the previous report made in Ghana [ 26 ], Botswana [ 12 ], Iran [ 30 ], and Ethiopia [ 14 ]. The isolation of S. flexneri from the gut of cockroaches in the FHEs might be a reflection of recent infected source as dose feeding experiments demonstrated that maximum survival shedding duration of cockroaches for Shigella was less than four days after they fed with standard inoculums via contaminated food [ 31 ].…”

“…Accordingly, a total of 1140 adult cockroaches, 730 from restaurants and 410 from cafeterias, were included for microbiological investigation. Since the cockroach infestation is high and cockroaches may probably carry the same amount of bacteria cockroaches were taken as a pool of 10 cockroaches as one batch [ 8 , 12 – 14 ].…”

Cockroaches as a Source of High Bacterial Pathogens with Multidrug Resistant Strains in Gondar Town, Ethiopia

“…It is known that isolates are the main causes of diverse types of nosocomial and community acquired infections, notably pneumonia, urinary tract infection, respiratory tract infection, skin infections, septicemia, and gastroenteritis [ 18 ]. Likewise previous reports have also indicated that the above-mentioned bacteria pathogens were the common isolates from cockroaches [ 10 , 19 – 21 ].…”

Antimicrobial susceptibility patterns of escherichia coli isolates from cockroaches in southwestern Iran

“…More than 33.3% of cockroach isolates have shown resistance to antimicrobials (Mpuchane et al, 2006). There are also many different virulence factors, which are usually encoded by plasmids, chromosomes, or bacteriophages (Tham, 2012).…”