Epidemiological Report on Outbreak Investigation of Chicken Pox in Muzaffarpur District, Bihar, India

Chicken pox or varicella is an acute infectious disease of childhood caused by varicella-zoster virus (VZV), belonging to the family Herpesviridae. Outbreaks of Chicken Pox were reported in 10 blocks in Muzaffarpur district in Bihar from 16 Jan 2016 till 7 Feb 2016. Outbreak investigation was done in 3 blocks in the district to identify the reasons of outbreak and to suggest remedial measures for its control. Discussion with the District authorities and medical and paramedical staff was done to know the background information of the affected areas, genesis of outbreak, investigations carried out so far and control measures undertaken, visit to the affected areas was done and environmental investigation, knowledge, attitude & practices of the community were also analyzed as per pre-planned questionnaire. Total 263 cases and 2 deaths due to Chicken Pox have been reported in Muzaffarpur from 10 blocks from Jan 2016 till Feb 7 2016. The disease afflicted almost all the age group but the incidence was more in the age group 1-14 years. Males were more affected than females in Block Mushahri and Meenapur while males and females are equally affected in Block Kurhani. The most common clinical manifestations observed were rash (100%), fever (88%) and headache (24%). The rash was generalized in all of the cases, and the first site was the trunk in the majority (60%) followed by face (20%) of the patients. Majority (54%) of the patients presented 51–100 lesions followed by 25-50 lesions (52%). The history of contact with a case of chickenpox was available in all the patients while none of them gave a history of vaccination against VZV. Majority of the cases recovered spontaneously without any major complications. The area was overpopulated with residents living in poorly structured houses. Majority were living in a hut with entire family with poor ventilation facilities, which led to the spread of the virus. Majority of the affected population were illiterate (54%) and unaware of the cause of the disease. The Health Workers viz: ASHAs and ANMs could play an important role in prevention of outbreak.