To determine the genomic profile of Salmonella Typhi causing typhoid fever, a detailed genomic level analysis was performed on whole genome sequences to identify mutations associated with the emergence of Extensively Drug Resistant (XDR) strains by comparative analysis of isolates from Pakistan, Bangladesh and India. The Pakistani isolates exhibited a significantly higher mutation rate, along with a higher proportion of modifiers and silent mutations as compared to others. The distinct genomic characteristics of Lahore isolates emphasizes the increasing prevalence of XDR Salmonella Typhi in Asian countries and underscore the significance of analyzing and comparing its genome with relevant strains. It also suggests a potential regional difference in selective pressure causing the mutations in the genome.

Index Terms- Enterobacteriaceae, Salmonella Typhi, Typhoid Fever, Whole Genome Sequencing