Routine immunization data management need assessment survey of selected health facilities and local government areas in Enugu State, June, 2015

Background: Japanese Encephalitis (JE) is a mosquito-borne disease caused by JE virus belongs to the family Flaviviridae. In Asia approximately 68,000 clinical cases among 10,000 deaths occurs every year. Although symptomatic JE is rare, the case-fatality rate among those with encephalitis can be as high as 30%. Permanent neurologic or psychiatric sequelae can occur in 30%–50% of those with encephalitis. The risk is highest in children aged 1-15 years, in rural areas and in the monsoon/post monsoon season. JE vaccine (JENVACR) development is a collaborative project between Bharat Biotech International Ltd, Hyderabad, India and National Institute of Virology, Pune, India. Methods & Materials: Virus strain (821564-XY) used in vaccine development which is isolated from the endemic region of Kolar, Karnataka, India. The world’s first fully-integrated, single use bioreactor used for the production of JE vaccine using Vero cell line. Purification is performed using chromatography techniques. Formulation has been carried out with alluminium hydroxide gel. Results: Non-clinical toxicology studies were conducted in lab animals and the vaccine has no toxic effects. The safety of this vaccine was established in a Phase-I study on healthy adult volunteers and the results further confirmed in phase II/III study. The efficacy of this vaccine was studied in endemic and non-endemic areas. The sero-protection of the RS.JEV (Chinese vaccine, SA 14-14-2) is 77.56% at 28th day and has a decrease of 5% after 6 months, whereas JENVACR showing sero-protection of 98.67% at 28th day of single dose vaccination and 99.78% after 56 days with a second dose vaccination. The Immunogenicity study has given 91% at 12 months, 67% at 18 months, 61% sero-protection even after 24 months. Conclusion: The other vaccines available against JE virus are live attenuated which is derived from the primary hamster kidney cell culture whereas vaccine JENVACR manufactured by Bharat Biotech is the first VERO cell derived inactivated indigenous vaccine which induces high immunity against JE virus in adults and children above one year and JENVACR is found stable for 2 years at 2-8◦C is commercially available. Based on the results it is concluded that JENVACR gives long-term protection against Japanese encephalitis infection.