Bacterial contamination of pork carcasses from Arusha, Tanzania

Abstract

Consumer demand for pork in Tanzania is driving growth of an increasing number of poorly equipped formal and informal slaugther facilities. To assess the potential public health challenges from these developments, we assessed the magnitude of microbial contamination of pork carcases from slaughterhouses in urban Arusha. Carcasses surface swabs (n = 90) from three slaughterhouses (designated A, B and C with carcass turnover of 1-30, 30-50 and 50-100 per day, respectively) were sampled and E. coli and Salmonella isolates (n = 1,632 and n = 177, respectively) were tested against a panel of 11 antibiotics using breakpoint assays. On average, E. coli and Salmonella were recovered from 71.1% and 66.7% of carcasses, respectively. Prevalence was highest (E. coli, 90.0% and Salmonella, 90.0%) for carcasses from site B, a facility where all slaughter operations, including eviscerations, were completed on the floor. The lowest prevalence (E. coli, 43.3% and Salmonella, 36.7%) was recorded for carcasses from Site C, a facility where most operations were completed with the carcasses hanging from overhead rails. Resistance to at least one antibiotic was observed in 71.2% of the E. coli isolates, most commonly to ampicillin (53.2%) followed by amoxicillin (38.8%) and sulfamethoxazole (31.0%). Approximately 45.2% of Salmonella isolates were resistant to at least one antibiotic while 23.2% were resistant to two or more of the tested antibiotics. Resistance to streptomycin (19.8%), trimethoprim (18.6%), ampicillin (16.9%) and sulfamethoxazole (13.6%) were most common. All isolates were susceptible to cefotaxime, ceftazidime, and chloramphenicol. These findings associate poor slaughter practices with bacterial carcass contamination and provide evidence for potential to contract antimicrobial resistant E. coli and Salmonella.. General Terms: Microbial load, multidrug resist