Whole genome sequencing of non-typhoidal Salmonellae serovars isolated from humans and poultry in Manipal India

Non-typhoidal Salmonellosis, a zoonotic infection associated with acute gastroenteritis is caused by non-typhoidal salmonellae (NTS). The NTS strains were isolated from poultry and patients using standard bacteriological methods. DNA was extracted using the Invitrogen Easy-DNATM Kit and then shipped to the Technical University of Denmark, Denmark (DTU) for whole genome sequencing. The genomic DNA were sequenced using the MiSeq Illumina platform. All the assembled sequences were examined using bioinformatics tools available at the Center for Genomic Epidemiology (CGE) to investigate phylogenetic relationships and to identify the sequence type (ST). The common NTS serovars found both among human and poultry were Salmonella Kentucky, Salmonella Weltevreden, and Salmonella Agona. Among the common NTS serovars between human and poultry, 18.19% (4/22) of the poultry NTS serovars shared identical sequences with 8.69% (2/23) of the NTS human serovars. 40.9% (9/22) of the poultry NTS serovars were closely related with 18.2% (4/22) of the human NTS serovars. This indicates that poultry could be an important receptacle for human non-typhoidal salmonellosis. Thus, a systematic and organized surveillance and supervision of the contamination sources and transmission route of the bacterial enteric pathogens especially in the food production chain is very much required to target the control measures to the critical points in the spread of the pathogens to the public. The WGS study in a developing country like India highlights the importance of the widespread introduction of this technology, which enables the understanding of epidemiology and microbiology of infectious diseases