An epidemiological investigation of a multisource outbreak of Crimean-Congo hemorrhagic fever in Gujarat.

It all started with the report from Shalby Hospital, Ahmedabad of two deaths with unusual presentation on Jan 18, 2011. Immediately investigations were carried out; to identify the etiological agent, source of outbreak, and mode of transmission, as well as, to propose a control measure based on the findings of the investigation. Extensive literature search, discussion with various scientific institutions, scientists and laboratory diagnosis suggested it to be case of Crimean-Congo Hemorrhagic Fever (CCHF). Accordingly a Case definition was worked out to further investigate the episode/outbreak. Door-to-door survey was carried out and hospital records were scrutinized. Collected data was analyzed in terms of time, place, and person. Laboratory investigation reports of case patients were also collated. We conducted environment investigation to find out the source of Infection. A total 13 case patients of CCHF were identified out of which 9 are positive for CCHF virus, 2 were negative for CCHF virus and in 2 instances, samples could not be taken because of early deaths of the cases. Among these 13 cases, 30.76% mortality rate was noted. Cases were reported in middle age group only. Environmental investigation also confirmed the presence of CCHF virus in Ticks. The outbreak was due to CCHF virus. State wide sero surveillance in animals is needed to identify prevalence of disease in Gujarat.