The Japanese encephalitis vaccine: An affordable answer to Asia’s “brain fever”

April 30, 2014 by Emeline Cokelet Meneken

This vaccine is the first vaccine manufactured in China to receive World Health Organization prequalification.

JE vaccine

Since achieving WHO prequalification, the JE vaccine from the Chengdu Institute of Biological Products provides JE immunity to hundreds of millions of children in the majority of JE-endemic countries. Photo: PATH/Aaron Joel Santos.

Each year, more than 2 million children die from just four illnesses: malaria, pneumonia, diarrhea caused by rotavirus, and Japanese encephalitis (JE). Today, we look at a vaccine against JE, the first vaccine manufactured in China to receive World Health Organization (WHO) prequalification.

The challenge

Often called “brain fever,” Japanese encephalitis (JE) begins like the flu but quickly progresses to a brain infection that kills nearly one in three people with the virus. Among its survivors, up to half suffer permanent neurological damage, such as paralysis, recurrent seizures, or the inability to speak.

The disease mainly strikes children in poor, rural communities in Southeast Asia and the Western Pacific, where four billion people live at risk of JE. Up to 70,000 cases are reported annually. The fate of those who become infected is a guessing game—there is no treatment for JE. The only viable solution is prevention through vaccination.

“Often called “brain fever,” Japanese encephalitis (JE) begins like the flu but quickly progresses to a brain infection that kills nearly one in three people with the virus.”

The vaccine

In October 2013, WHO gave its critical stamp of approval to an affordable JE vaccine to protect children from the virus. Through an innovative partnership with China’s Chengdu Institute of Biological Products, PATH helped to scale up the vaccine—which had been used successfully to protect more than 200 million of China’s children—and prepare it for WHO approval so that it could reach the roughly two dozen countries at risk of JE.

The vaccine is the first produced in China to receive WHO prequalification, marking the country’s foray in the global vaccine marketplace. And WHO’s approval means the vaccine qualifies for critical international support, making it affordable for the countries where it can make the most impact.

The future

Even before WHO prequalification, PATH helped 11 countries outside of China license or use the vaccine. In India alone, 88 million children have been vaccinated against JE since 2006.

Last month, another country, Laos, launched its first immunization campaign against JE in two districts with the goal of reaching 170,000 children in two weeks.

The GAVI Alliance has added the vaccine to its portfolio to provide financing for low-income countries at highest risk for JE, an important step in expanding the vaccine’s reach. And China’s arrival as a WHO-recognized vaccine manufacturer could fundamentally shift how vaccines for other diseases are made, delivered, and priced for the developing world in the future.