Japanese Encephalitis (JE) vaccination programme

17DEC 2011

Japanese Encephalitis (JE) vaccination programme has made progress in the country. JE vaccination campaign was launched initially during 2006-07 in 11 high endemic districts of Uttar Pradesh, Karnataka, Assam and West Bengal achieving an overall coverage rate of 88.39%.

• Due to intensified efforts by Government of India, JE vaccination has significantly contributed to the decline of JE positive cases from 35.88% 
•  State of Uttar Pradesh which contributes more than 80% of cases and deaths respectively in the country.

Japanese encephalitis (Japanese: 日本脳炎, Nihon-nōen)—previously known as Japanese B encephalitis

• —is a disease caused by the mosquito-borne Japanese encephalitis virus.
• The Japanese encephalitis virus is a virus from the family Flaviviridae.
• Domestic pigs and wild birds (herons) are reservoirs of the virus;
• transmission to humans may cause severe symptoms. Amongst the most important vectors of this disease are the mosquitoes Culex tritaeniorhynchus and Culex vishnui.
• This disease is most prevalent in Southeast Asia and the Far East.

SYMPTOMS

• Japanese encephalitis has an incubation period of 5 to 15 days and the vast majority of infections are asymptomatic( An asymptomatic carrier (healthy carrier or just carrier) is a person or other organism that has contracted an infectious disease, but who displays no symptoms. ):
• only 1 in 250 infections develop into encephalitis.
• Severe rigors mark the onset of this disease in humans.
• Fever, headache and malaise are other non-specific symptoms of this disease which may last for a period of between 1 and 6 days.
• Signs which develop during the acute encephalitic stage include neck rigidity, cachexia, hemiparesis,
•  convulsions and a raised body temperature between 38 and 41 degrees Celsius.
• Mental retardation developed from this disease usually leads to coma.
• Mortality of this disease varies but is generally much higher in children.
• Transplacental spread has been noted.
• Life-long neurological defects such as deafness, emotional lability and hemiparesis may occur in those who have had central nervous system involvement. In known cases some effects also include nausea, headache, fever, vomiting and sometimes swelling of the testicles.