The 2010 outbreak of cholera among workers of a Jute Mill in Kolkata,West Bengal,India

On 10 march 2010,an outbreak of diarrhoeal disease was reported among workers of a jute mill in kolkata,west bengal,india. the cluster was investigated to identify the agent(s) and the source of infection and make recommendations. a suspected case of cholera was defined as having >3 loose watery stools in a 24-hour period and searched for case-patients in the workers' colony. the outbreak was described by time,place,and person,and a case-control study was conducted to identify the source of infection. rectal swabs were collected from the hospitalized case-patients,and the local water-supply system was assessed. in total,197 case-patients were identified among 5,910 residents of the workers' colony (attack rate 3.33%). fifteen of 24 stool samples were positive for vibrio cholerae o1. the outbreak started on 7 march,peaked on 11 march,and ended on 16 march 2010. compared to 120 controls,60 cases did not differ in terms of age and socioeconomic status. drinking-water from the reservoir within the mill premises was associated with an increased risk of illness [odds ratio: 26.7,95% confidence interval (ci) 11.4-62.6) and accounted for most cases (population attributable risk percentage=82%,95% ci 70.8-92.9). an outbreak of cholera occurred among workers of the jute mill due to contamination of the drinking-water reservoir. it occurred within a few days of re-opening of the mill after the workers' strike. health authorities need to enforce disinfection of drinking-water and regularly test its bacteriological quality,particularly before re-opening of the mill after the strike. © international centre for diarrhoeal disease research.