An Approach of Acute Encephalitis Syndrome in Muzaffarpur, Bihar; A Different Perspective

Acute encephalitis syndrome (AES) is a disease characterized by fever and mental confusion,
disorientation, delirium, or coma. It could be due to various causes such as viruses, bacteria, fungus,
parasites, spirochetes, chemical, and toxins. This chapter is an outcome of an Epidemiological
investigation of AES occurred in Muzaffarpur, Bihar in 2011 which was done by a team consisting of
experts from various disciplines. The team visited Muzaffarpur, from 14th to 20th July 2011 and
reviewed the situation of deaths among children due to AES, as directed by the Authorities. A total of
147 cases of fever with altered sensorium were admitted between 11th June to 18th July 2011 in a
private hospital and a Medical College Hospital of Muzaffarpur. Out of these, 54 patients died
indicating case fatality rate of 36.73%. Clinico-epidemiological and environmental evidence supports
the diagnosis of Acute Encephalitis Syndrome which has significant mortality, affecting predominantly
rural population with poor sanitation and presence of wild rats. No significant association of litchi
consumption and poor nutritional status of children with AES disease were found. Evidences suggest
that there were increased chances of contacts between cases and wild rats during the period of
occurrence of outbreak. Key observation was the sudden drop in incidence of cases with rainfall as
during and just after the rain children abandons the outdoor games in farmlands/ litchi gardens due to
accumulation of water in these areas and exposure from the rodents prevented Etiological agent
could not be identified by laboratory tests. Time, place and person distribution of cases is suggestive
of infectious disease of short incubation period (<1 day) having wider spectrum of sub clinical and
clinical phases & lifelong immunity after first infection.