title: Epidemiological investigation of the jaundice outbreak in lalkuan, nainital district, uttarakhand.
abstract: BACKGROUND
  In March 2013, cases of acute hepatitis were reported from Lalkuan, Nainital district. We investigated the outbreak to identify the source of infection and to facilitate control measures.
  
  
  OBJECTIVE
  To study the distribution of hepatitis cases, to find the source of infection, and to initiate the control measures in the affected area.
  
  
  METHODS
  WE DEFINED A CASE OF ACUTE HEPATITIS AS THOSE CASES THAT HAD JAUNDICE WITH AT LEAST ONE OF THE FOLLOWING SYMPTOMS: Dark urine, fever, pain in abdomen, vomiting, and loss of appetite in the affected area between January and March 2013. Door-to-door survey was carried out. Thirteen blood samples were randomly collected from jaundice cases for immunoglobulin M (IgM) antibody for hepatitis A virus (HAV) and hepatitis E virus (HEV). Water samples were collected to test residual chlorine.
  
  
  RESULTS
  Total 2,785 individuals were surveyed; of which 240 were suffering from acute viral hepatitis (attack rate (AR) = 8.61%). Out of 13 serum samples, 10 were found positive for HEV IgM antibodies and three cases had IgM antibodies for both HAV and HEV, which confirmed a hepatitis E outbreak. The difference in attack rate of hepatitis of both the sexes was statistically significant (P < 0.001). The attack rate was significantly higher in age groups >12 years of age (P < 0.001). Environmental investigation also confirmed the sewage contamination of drinking water in the distribution system. The attack rate was much higher (29.4%) among those who were exposed to the leaking pipeline than the nonexposed (χ(2) = 574.26, P < 0.01).
  
  
  CONCLUSIONS
  HEV was confirmed as the major etiological agent in this outbreak that was transmitted by contaminated drinking water. The recognition of early warning signals, timely investigation, and application of specific control measures can contain the outbreak.
authors: Department of Community Medicine, Government Medical College, Haldwani, Nainital, Uttarakhand, India.
authors: Sadhana
authors: S
authors: Awsathi
authors: Department of Microbiology, Government Medical College, Haldwani, Nainital, Uttarakhand, India.
authors: Vinita
authors: V
authors: Rawat
authors: Department of Community Medicine, Government Medical College, Haldwani, Nainital, Uttarakhand, India.
authors: Chandra Mohan Singh
authors: CM
authors: Rawat
authors: Department of Community Medicine, Government Medical College, Haldwani, Nainital, Uttarakhand, India.
authors: Vandana
authors: V
authors: Semwal
authors: Department of Community Medicine, Government Medical College, Haldwani, Nainital, Uttarakhand, India.
authors: Sunil Janki
authors: SJ
authors: Bartwal
keywords: Epidemiological investigation; environmental sanitation; feco-oral route; infective hepatitis E; serological examination