An Epidemiological Study of AES (Acute Encephalitis Syndrome) Outbreak 2019 in Muzaffarpur District, Bihar, India

Acute encephalitis syndrome (AES) is a major public health concern in India, especially in Muzaffarpur, Bihar, as outbreaks of this neurological disorder have brought on significant morbidity and mortality. It is usually characterized by sudden fever, seizures, confusion, and altered mental status in children along with infectious agents, environmental factors, and malnutrition. It is evident during litchi harvest (April-June), affecting malnourished children from poor families. Among 622 AES cases from May till July 2019; a significant majority were found to have higher mortality and morbidity indices among female Scheduled Caste children. Access barriers in the social and cultural context delayed health care in the event of morbidity. Earlier speculation about associating litchi intake was set aside as most of affected children stayed far from orchards. Clinically, it manifests with fever starting suddenly associated with seizures, altered sensorium, hypoglycemia, hyponatremia, and elevated biomarkers CPK, LDH, and ammonia. High humidity and inadequate mosquito net use are linked. However, these observational studies could not show laboratory evidence of vectors of Japanese encephalitis. Priorities in action include strengthening surveillance, nutrition, education, and better health care access.