Aims: In view of the changing sensitivity pattern of Salmonella, this study was carried out to investigate the current antibiogram and clonal relatedness among the drug-resistant Salmonella enterica serovar Typhi in Northern India.
Results: Re-emergence in the sensitivity to chloramphenicol and cotrimoxazole with increase in the resistance to various quinolones has been observed. The efficacy of nalidixic acid resistance to be used as a marker for decrease in sensitivity to ciprofloxacin may vary. Clonal differences on the basis of amplification of repetitive elements (rep-PCR) were found in the two different areas within the same region.
Conclusions: The present study creates a paramount baseline for rationalizing the judicious use of quinolones and re-examine the use of chloramphenicol and cotrimoxazole. Molecular analysis of clinical Salmonella isolates depicts the clonal expansion of the isolates that may serve as a reference to which newer outbreak strains can be compared. rep-PCR techniques may be useful in molecular discrimination of isolates for better understanding of the Salmonella epidemiology and as a basis for development of rational control strategies.