Epidemiological investigation of viral hepatitis E outbreak in two colocated training centers

Background: A high number of jaundice cases were reported from two colocated training centers in North India. This outbreak was investigated to describe the epidemiology, identify risk factors, and recommend preventive and control measures.

Methods: Initial line list was prepared, and case definition was defined as "the presence of icterus or passage of yellow-colored urine with fever/anorexia/vomiting/abdominal pain in a resident of Military Station A between 03/04/2016 to 06/06/2016". Case search was conducted through surveillance. An unmatched 1:1 case-control study was conducted to evaluate the associated risk factors. All cases were tested for hepatitis markers. Environmental investigation of food and water sources was conducted to identify the source of infection.

Results: Of 172 cases, all were males from two co-located military training centers (attack rate, 4.7%). Clinical features included icterus (100%), yellowish discoloration of urine (98.9%), anorexia (97.22%), fever (80%), nausea/vomiting (56%), and abdominal pain (52.77%). Only one case (0.6%) had complication of fulminant hepatitis, and there were no deaths (CFR = 0%). Consumption of juice with ice from juice shops was significantly associated with illness (Odds Ratio-14.3 [95%CI 7.4-27.6]). Of 172 cases, 167 (97.1%) tested anti-HEV-IgM positive. Juice shops in training centers were using ice made from contaminated water with positive coliform test. All other water samples tested satisfactory. No cross-contamination of water pipelines with sewage was observed.

Conclusion: Epidemiological evidence concludes that a large viral hepatitis E outbreak was likely caused by consumption of juice with contaminated ice. Early stoppage of contaminated ice usage led to timely control of the outbreak.