Dataset Information

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

ABSTRACT:

Background

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.

Methodology

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.

Principal findings

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.

Conclusions

Our results strongly suggest that the locally-produced JE-MBV given to 1-5 years old Vietnamese children was efficacious.

SUBMITTER: Marks F

PROVIDER: S-EPMC3521705 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Publications

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

Marks Florian F Nguyen Thi Thu Yen TT Tran Nhu Duong ND Nguyen Minh Hong MH Vu Hai Ha HH Meyer Christian G CG You Young Ae YA Konings Frank F Liu Wei W Wierzba Thomas F TF Xu Zhi-Yi ZY

PLoS neglected tropical diseases 20121213 12

<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 ai ...[more]

PMID: 23272262

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Dataset Information

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

Background

Methodology

Principal findings

Conclusions

Publications

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

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