Cholera Outbreak Linked with Lack of Safe Water Supply Following a Tropical Cyclone in Pondicherry, India, 2012

Journal of Health, Population and Nutrition (JHPN)

K. David, Joseph¹  Jayaraman, Yuvaraj¹  Ponnaiah, Manickam¹  Vadivoo, Selvaraj¹  V. Murhekar, Manoj¹  Joshua, Vasna¹  Fredrick, Tony¹ 

关键词: Cholera;    Outbreak;    Post-cyclone;    India;   

DOI  :  10.3329/jhpn.v33i1.3192

来源: International Centre for Diarrheal Disease Research, Bangladesh (ICDDR,B)

【 摘 要 】

In the aftermath of a severe cyclonic storm on 7 January 2012, a cluster of acute diarrhoea cases was reportedfrom two localities in Pondicherry, Southern India. We investigated the outbreak to identify causesand recommend control measures. We defined a case as occurrence of diarrhoea of more than three loosestools per day with or without vomiting in a resident of affected areas during 6-18 January 2012. Weused active (door-to-door survey) and stimulated passive (healthy facility-based) surveillance to identifycases. We described the outbreak by time, place, and person. We compared the case-patients with up tothree controls without any apparent signs and symptoms of diarrhoea and matched for age, gender, andneighbourhood. We calculated matched odds ratio (MOR), 95% confidence intervals (CI), and populationattributable fractions (PAF). We collected rectal swabs and water samples for laboratory diagnosis and testedwater samples for microbiological quality. We identified 921 cases and one death among 8,367 residents(attack rate: 11%, case-fatality: 0.1%). The attack rate was the highest among persons of 50 years and above(14%) and females (12%). The outbreak started on 6 January and peaked on the 9th and lasted till 14 January.Cases were clustered around two major leakages in water supply system. Nine of the 16 stool samplesyielded V. cholerae O1 Ogawa. We identified that consumption of water from the public distribution system(MOR=37, 95% CI 4.9-285, PAF: 97%), drinking unboiled water (MOR=35, 95% CI 4.5-269, PAF: 97%), anda common latrine used by two or more households (MOR=2.7, 95% CI 1.3-5.6) were independently associatedwith cholera. Epidemiological evidence suggested that this outbreak was due to ingestion of watercontaminated by drainage following rains during cyclone. We recommended repair of the water supplylines, cleaning-up of the drains, handwashing, and drinking of boiled water. Key words: Cholera; Outbreak; Post-cyclone; India

【 授权许可】

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