Emergence of fluoroquinolone resistance in Salmonella enterica serovar Typhi in Andaman and Nicobar Islands, India

According to a recent report, re-emergence of chloramphenicol susceptible Salmonella enterica serovar Typhi and Paratyphi A was observed in Chennai [12] . Blood and stool samples were collected from suspected patients (both adult and children) of typhoid fever attending the outpatient departments or admitted to two referral hospitals viz., G.B. Pant Hospital and INHS Dhanwantari, in Port Blair, prior to the administration of antimicrobial drugs. The antibiotic susceptibility tests were done by Kirby-Bauer disk diffusion method [15] according to Clinical and Laboratory Standards Institute (CLSI) guidelines [16] using commercially available disks (Hi-media Laboratories, Mumbai) of ampicillin (10 μg, AMP), carbenicillin (100 μg, CAR), imipenem (10 μg, IMP), amikacin (30 μg, AMK), chloramphenicol (30 μg, CHL), co-trimoxazole (25 μg, CoT), nalidixic acid (30 μg, NAL), norfloxacin (10 μg, NOR), ciprofloxacin (5 μg, CIP), ofloxacin (5 μg, OFX), gatifloxacin (5 μg, GAT), gentamycin (10 μg, GEN), nitrofurantoin (300 μg, NIT), and tetracycline (30 μg, TET), azithromycin (30 μg, AZT), cephalothin (30 μg, CEF), cefuroxime (5 μg, CXM), cefixime (30 μg, CFM), ceftriaxone (30 μg, CRO).