Effectiveness of the Viet Nam produced, mouse brain-derived, inactivated Japanese encephalitis vaccine in Northern Viet Nam.

<h4>Background</h4>Japanese encephalitis (JE) is a flaviviral disease of public health concern in many parts of Asia. JE often occurs in large epidemics, has a high case-fatality ratio and, among survivors, frequently causes persistent neurological sequelae and mental disabilities. In 19...

Full description

Saved in:
Bibliographic Details
Main Authors: Florian Marks, Thi Thu Yen Nguyen, Nhu Duong Tran, Minh Hong Nguyen, Hai Ha Vu, Christian G Meyer, Young Ae You, Frank Konings, Wei Liu, Thomas F Wierzba, Zhi-Yi Xu
Format: article
Language:EN
Published: Public Library of Science (PLoS) 2012
Subjects:
Online Access:https://doaj.org/article/52013100c3f242fba3c69c7e7caf7bb6
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:<h4>Background</h4>Japanese encephalitis (JE) is a flaviviral disease of public health concern in many parts of Asia. JE often occurs in large epidemics, has a high case-fatality ratio and, among survivors, frequently causes persistent neurological sequelae and mental disabilities. In 1997, the Vietnamese government initiated immunization campaigns targeting all children aged 1-5 years. Three doses of a locally-produced, mouse brain-derived, inactivated JE vaccine (MBV) were given. This study aims at evaluating the effectiveness of Viet Nam's MBV.<h4>Methodology</h4>A matched case-control study was conducted in Northern Viet Nam. Cases were identified through an ongoing hospital-based surveillance. Each case was matched to four healthy controls for age, gender, and neighborhood. The vaccination history was ascertained through JE immunization logbooks maintained at local health centers.<h4>Principal findings</h4>Thirty cases and 120 controls were enrolled. The effectiveness of the JE vaccine was 92.9% [95% CI: 66.6-98.5]. Confounding effects of other risk variables were not observed.<h4>Conclusions</h4>Our results strongly suggest that the locally-produced JE-MBV given to 1-5 years old Vietnamese children was efficacious.