Outbreak Of Ceftriaxone-Resistant Salmonella Enterica Serotype Typhi Attributed To Eating Chicken At Hotel X, Tiruchirappalli, India, 2018

Background: Third-generation cephalosporin is widely used for typhoid treatment. In May 2018, India's National Centre for Disease Control based Antimicrobial resistance surveillance network notified through Tamil Nadu State Surveillance Unit about clustering of ceftriaxone-resistant Salmonella enterica serotype Typhi cases in Tiruchirappalli city, Central Tamil Nadu. Team led by State public health department investigated to identify risk factors. Methods and materials: We defined case as occurrence of culture positive Salmonella Typhi with ceftriaxone-resistance in a resident of Tiruchirappalli city, during January-June 2018. We identified cases by reviewing records of hospitals and laboratories. We drew epidemic curve, plotted spot map, calculated incidence by age and gender. Based on descriptive epidemiology and few case-patients interview, we hypothesized that eating at hotel X could be potential exposure. We tested hypothesis with case-control study. We defined case as ceftriaxone-resistant typhoid case-patient and control as ceftriaxone-susceptible typhoid case-patient. We conducted second case-control study to identify the food item caused the outbreak. We defined case as ceftriaxone-resistant typhoid case-patient who ate at hotel x and control as companion who accompanied case to hotel X. We computed odds ratios (OR) and 95% confidence interval (CI). We screened food handlers of hotel X for typhoid carrier status by stool culture and widal test. Results: We identified that 7 (14%) of 51 typhoid case-patients with ceftriaxone-resistant. Their median age was 23 years (Range: 12–42) and 5 were men. All the seven had fever and hospitalized (Median stay: 9 days; Range: 4–23) and three reported abdominal pain. We identified clustering of cases around hotel X. Five of the 7 cases reported history of consumption at hotel X prior to illness. Incidence of ceftriaxone-resistant typhoid were higher among the cases who ate at hotel X than controls (OR = 37.7; 95% CI: 2.7–3173.0). Incidence of ceftriaxone-resistant typhoid were higher among the cases who ate chicken gravy at hotel X than controls (OR = 16.0; 95% CI: 1.1–234.2). Food handlers did not have typhoid carrier status. Conclusion: The cluster of ceftriaxone-resistant Salmonella Typhi was due to eating chicken gravy at hotel X in central Tamil Nadu. We recommended proper processing of chicken and continuing surveillance for ceftriaxone-resistant.