Antimicrobial and Genomic Characterization of Salmonella Nigeria from Pigs and Poultry in Ilorin, North-central, Nigeria.

INTRODUCTION: Non-typhoidal Salmonella are major foodborne pathogens causing serious challenges to public health and food safety worldwide. This study aimed to determine the resistance, virulence genes, sequence type, using multi-locus sequence typing, plasmids and Single Nucleotide Polymorphisms (SNPs) of Salmonella enterica subsp. enterica serovar Nigeria (S. Nigeria) from livestock in Ilorin, North central Nigeria. METHODOLOGY: A total of 1,500 samples from pig (feces; n = 600) and poultry (feces, postmortem samples; n = 900) were collected and analyzed between 2014 to 2017. Presumptive Salmonella isolates were characterized by Whole Genome Sequencing (WGS). RESULTS: We recovered nine S. Nigeria serovars. All the isolates harbored a single point mutation parC(T57S) in addition to qnrB19 and the tetA gene. Furthermore, two plasmids, Col(pHAD28) and IncQ1 predicted to encode qnrB19 and tetA genes, respectively, were detected in all the strains. All the isolates belonged to a single sequence type (ST) 4911, the SNP-based phylogeny showed all the isolates to be highly related, in addition two clinical isolates from the United Kingdom (UK) and Canada, collected outside of this study, also fell into this cluster. Twenty virulence genes were identified from Salmonella Pathogenicity Islands (SPI), chromosomal and fimbriae loci. CONCLUSIONS: This study highlights the roles of pig and poultry in the emergence and spread of S. Nigeria serovar in Nigeria, sub-Sahara Africa. It also highlighted the importance of WGS in clinical and epidemiological surveillance. There is the need for collaborative research studies to investigate the public health importance of Salmonella enterica serovar Nigeria.

Investigating Salmonella Eko from Various Sources in Nigeria by Whole Genome Sequencing to Identify the Source of Human Infections.

Twenty-six Salmonella enterica serovar Eko isolated from various sources in Nigeria were investigated by whole genome sequencing to identify the source of human infections. Diversity among the isolates was observed and camel and cattle were identified as the primary reservoirs and the most likely source of the human infections.

Serotypes, antimicrobial profiles, and public health significance of Salmonella from camels slaughtered in Maiduguri central abattoir, Nigeria.

AIM: This study aimed at determining the serotypes, antimicrobial profiles, and public health importance of Salmonella strains from camels slaughtered at Maiduguri central abattoir, Nigeria. MATERIALS AND METHODS: Two hundred samples were obtained from camel comprising of intestines, feces, liver, and spleen (n=50 each). Non-lactose fermenting dark center Salmonella colonies were identified using standard biochemical techniques, serotyped and subjected to antimicrobial susceptibility test using minimum inhibition concentration method. RESULTS: Out of the 200 samples collected, 17 were Salmonella positive (spleen=7, intestine=6, feces=3, and liver=1) with a prevalence of 8.5%. Five serotypes comprising Salmonella Eko, 7 (3.5%), Salmonella Uganda, 4 (2.0%), Salmonella Amager, 2 (1.0%), Salmonella Westhampton, 2 (1.0%), and Salmonella Give, 2 (1.0%) were incriminated. Majority of the serotypes were sensitive to the antimicrobials, but one Salmonella Amager exhibited resistance to streptomycin, and one each of Salmonella Uganda and Salmonella Eko were resistant to sulfamethoxazole. CONCLUSION: This study revealed the prevalence and the antibiotic resistance profile of newly emerging Salmonella from camels in the northeast of Nigeria, which can serve as a means for the transmission of Salmonella to human. Therefore, there is a need for the establishment of national Salmonella surveillance and control programs.

Persistence of fluoroquinolone-resistant Salmonella enterica serovar Kentucky from poultry and poultry sources in Nigeria.

INTRODUCTION: This study investigated the antimicrobial resistance and clonality of Salmonella enterica serotype Kentucky in poultry and poultry sources in Nigeria, and compared the isolates with the clone of S. Kentucky STI98-X1 CIPR using (PFGE) and (MIC). METHODOLOGY: Fecal samples from chickens and poultry sources (litter, water, rodent and lizard fecal samples) were collected from  fourteen (14) poultry farms in 2007, 2010 and 2011 and were analyzed for S. Kentucky. RESULTS AND CONCLUSIONS: Six percent of the samples were positive for S. Kentucky - all resistant to nalidixic acid and ciprofloxacin. The isolates are grouped within the PFGE cluster X1 of S. Kentucky STI98 CIPR, indicating the association to the emerging and widely spread CIPR S. Kentucky clone with poultry and poultry sources.