3rd Bi-Regional Meeting on Control of Japanese Encephalitis (26-27 April 2007) - Meeting Report
The Third Biregional Meeting on Control of Japanese Encephalitis (JE) was held in Ho Chi Minh City, Viet Nam from 26 to 27 April 2007. Efforts to control JE through immunization have grown significantly since the second biregional meeting in 2005, which was also hosted by the World Health Organization (WHO) and Program for Appropriate Technology in Health (PATH). Despite significant advances, the burden of JE is still great in many countries of the Western Pacific and South-East Asia regions.
The objectives of the workshop were:
(1) to review progress made by countries in JE control through immunization;
(2) to share, update and develop a consensus on the latest developments in surveillance standards, laboratory diagnostics and immunization strategies; and
(3) to reach an agreement on activities over the next two years towards JE control in individual countries.
Defining the burden of JE illness through routine surveillance is the first step towards informing country-level decisions about JE vaccine introduction. Several countries have initiated or enhanced JE surveillance by integrating it in routine reporting systems, and WHO’s standards for acute encephalitis surveillance have facilitated this process. Participants offered valuable input towards the further refinement of these surveillance standards. Challenges still remain, however, in particular with regard to the collection and testing of samples and the complexities of laboratory diagnostics. The recent development of the JE laboratory network will assist in providing support and guidance to countries. The impact of long-term disability on those that survive JE infection was recognized as very important in regard to understanding overall JE disease burden. Methods for evaluating disability were discussed, and a related tool developed by the University of Liverpool is currently being refined through field evaluation.
The response to a significant JE outbreak in 2005 in Nepal and India helped lay groundwork for planning and implementation of new JE immunization programmes in these two countries. Responding with unprecedented speed, the national governments of both countries introduced the SA 14-14-2 vaccine through campaigns before the onset of the monsoon season. More than 11 million children were vaccinated in 2006. These experiences—coupled with the affordability of the SA 14-14-2 vaccine—are encouraging other endemic countries throughout the two regions to introduce JE vaccine. Lessons learnt and continued implementation of long-term strategies, in which campaigns are followed by inclusion of JE vaccine in the country’s routine EPI, were among several important presentations made to the group.
Investigators presented data that are expanding the safety and efficacy profiles of available JE vaccines and providing information on how JE vaccine can best be included in routine immunization programmes. Recent studies have yielded crucial information on the SA 14-14-2 vaccine, including the acceptability of co-administration with measles vaccine, demonstrating that the SA 14-14-2 vaccine can be given at a routine EPI visit; long-term efficacy; and extended safety, reactogenicity, and immunogenicity data following introduction in new areas. Information was presented on several other JE vaccines in development, including tentative timelines for their availability in the global market.
Identifying financial support for JE vaccine introduction is an important element of developing control plans. Representatives from several countries presented their individual strategies. Countries considering the introduction of JE vaccine felt their national governments could support the costs of a routine programme given the affordable price of the SA 14-14-2 vaccine, but initial campaigns would require external financial support. Donor support will be key to advancing the agenda. As such, options for identifying external resources and fostering partnerships were central elements of discussion.