Molecular characterization and antibiotic resistance profiles of Salmonella isolated from fecal matter of domestic animals and animal products in Nairobi

Abstract

Background Salmonella has significant public health implications causing food borne and zoonotic diseases in humans. Treatment of infections due to Salmonella is becoming difficult due to emergence of drug resistant strains. There is therefore need to characterize the circulating non-typhoidal Salmonella (NTS) serovars in domestic animals and animal products in Kenya as well as determine their antibiotic resistance profiles.MethodsA total of 740 fecal samples were collected from cows (n = 150), pigs (n = 182), chicken (n = 191) and chicken eggs (n = 217) from various markets and abattoirs in Nairobi. The prevalence of NTS serovars using culture techniques and biochemical tests, antimicrobial sensitivity testing using disc diffusion method of the commonly prescribed antibiotics and phylogenetic relationships using 16S rRNA were determined.ResultsThe results showed that the overall prevalence of Salmonella was 3.8, 3.6, 5.9 and 2.6% for pigs, chicken, eggs and cows respectively. Two serovars were isolated S. Typhimurium (85%) and S. Enteritidis (15%) and these two serovars formed distinct clades on the phylogenetic tree. Forty percent of the isolates were resistant to one or more antibiotics.ConclusionThe isolation of Salmonella Typhimurium and Salmonella Enteritidis that are resistant to commonly used antibiotics from seemingly healthy animals and animal products poses a significant public health threat. This points to the need for regular surveillance to be carried out and the chain of transmission should be viewed to ascertain sources of contamination.

Phenotype and Molecular Characterization of Antibiotic Resistance of Salmonella spp. from Cattle in Abidjan District, Côte d'Ivoire

“…Lower rates compared to those obtained in our study (less than 1%) were reported by Smith et al [36]. In addition, high rates of resistance to nalidixic acid have been reported in Kenya (12%) [37], India (17.9% and 24.5%) [38], Romania (65.1%) [39]. However, the low rate observed in our study could be explained by the fact that fluoroquinolones are not widely used in cattle breeding in Côte d'Ivoire.…”

“…This prevalence of 20% of Salmonella strains determined in our study is higher than that determined by Alemayehu et al [21] who reported a prevalence of 7.1%. Studies in Ethiopia (2.3%) and Nairobi (2.6%) reported lower prevalences than those obtained in this study [22,23]. Significantly lower carriage of Salmonella has been reported in cattle in Japan and Great Britain with prevalence of 0.5% and 1.4% respectively [24,25].…”

Antimicrobial resistance genes in Salmonella and Escherichia coli isolates from chicken droppings in Nairobi, Kenya

“…The chicken are often administered antibiotics for prevention and treatment of diseases [12, 13]. Previous studies on antimicrobial resistance have revealed high resistance levels in bacterial isolates from rectal swabs of Kenyan chicken [14, 15]. However, much less has been investigated on the associated antimicrobial resistance genes.…”

Isolation and characterization of antibiotic susceptibility profile of <i>Salmonella</i> species isolated from abattoir environment

“…Salmonellae have been reported from abattoir settings in different parts of Nigeria such as Osun State, (Omololu-Aso et al, 2017); Port Harcourt, (Ire et al, 2017); Benue State, (Nseabasi-Maina et al, 2017); Sokoto, (Bagudo et al, 2014;Faleke et al, 2017). Also from other Africa regions in Nairobi, Kenya (Nyabundi et al, 2017); Kampala, Uganda (Tinega et al, 2016); Mansoura, Egypt (Sallam et al, 2014) and Modjo and Bishoftu, Ethiopia (Kuma et al, 2017). Salmonella are among organisms currently under public health surveillance for antimicrobial resistance (NARMS, 2013).…”