Antibiotic Profile and Molecular Characterization of Typhoidal Salmonellosis among Abattoir Workers in the Southern Region of Nigeria

Abstract

Typhoid fever remains endemic in most developing countries with large scale transmission through contaminated food and drinking water. Since 2000s, animal and their products have been found to be a common food source for Typhoidal infections. A total of 90 blood specimens, 45 samples each were collected from abattoir and non-abattoir workers in Akwa Ibom State and were screened for Salmonella species using standard cultural and serological techniques. The overall prevalence rate was 12 (13.3%). Salmonella species were distributed in all the three senatorial districts of the State. Percentage distribution of Salmonella isolates was 3 (3.3%) for Uyo, 4 (4.4%) for Eket and 5 (5.6%) were isolated from Ikot Ekpene districts. Out of 90 human subjects screened, 12 (13.3%) were positive and 5 (5.6%) were isolated from non-abattoir while 7 (7.7%) were isolated from abattoir workers. In this study, serological significant titre of ≥160 of Typhoid fever cases was confirmed by blood culture. According to sero-grouping and source of sample collection 4.4% S. typhi was isolated from abattoir workers followed by S. paratyphi A (3.3%) while S. typhimurium and S. gallinarum (2.2%) and S. enteritidis (1.1%). Increase prevalence of Salmonella serovars such as S. gallinarium, S. typhi, S. Typhimurium and S. enteritidis with regular consumption of slaughter meat and other product without proper disinfection and appropriate boiling, represent a serious public health risk in Akwa Ibom State. Demographic data obtained in this study showed that majority of the abattoir workers across the three districts were within the ages of 21 to 30 (33%), 39% were none graduate while 30.4% were secondary school leavers. Fever was recorded as the highest clinical signs and symptoms followed by headache, abdominal cramps, diarrhoea and vomiting. Generally, all the isolates identified as Salmonella were tested for their susceptibility to antimicrobial agents. The results showed that Chloramphenicol, Ciprofloxacin and Cefuroxine were 100% sensitive to S. gallinarum, S. paratyphi A, 93% susceptible to S. typhi and 80% to S. typhimurium and S. enteritidis. Whereas all isolates were 100% resistant to Septrin, Tetracycline and Ampicillin antibacterial agents used. The emergence of multiple drugs resistant Salmonella from abattoir workers shows that the continuous use of drugs in animal husbandry as growth promoters should be re-examined. Other factors as sources of Salmonella contamination in slaughter markets can be minimized by good hygienic practices and biosecurity measures.