Japanese encephalitis laboratory network - overview
Japanese encephalitis (JE) is an important cause of death and disability and is a pressing public health problem for many countries in Asia. Substantial advances have been made in recent years in the development of improved JE vaccines and in the availability of high-quality commercial diagnostics that can be used for surveillance. Subsequently, many countries in the Region have established laboratory-supported JE surveillance. Several countries have introduced JE vaccine into their routine vaccination programmes and enhanced surveillance activities are needed to determine the disease burden and to monitor vaccination programmes.
In 2008-2009, the JE laboratory network was established to improve the capability for JE case confirmation among countries either known or suspected to be endemic for JE in the Western Pacific Region, as recommended by the 17th TAG meeting in 2008. These countries are Cambodia, China, the Lao People's Democratic Republic, Malaysia, Papua New Guinea, the Philippines and Viet Nam.
The newly established JE laboratory network was formed based on the WHO polio and measles/rubella laboratory network models. Some WHO measles/rubella laboratories have also been designated as WHO JE laboratories. The purpose of this network is to improve and standardize the capability of JE diagnosis in countries where the disease is endemic. The network consists of one global specialized laboratory (GSL) in Japan, two regional reference laboratories (RRLs) in China and the Republic of Korea, and seven national laboratories (NLs) in Cambodia, the Lao People’s Democratic Republic, Malaysia, Papua New Guinea, the Philippines and Viet Nam (north and south).
The second JE laboratory network meeting was held on 24 February 2010 during the second Meeting on Vaccine Preventable Diseases Laboratory Networks in the Western Pacific Region and the third meeting was organized from 30 May to 1 June 2011 jointly with the 5th bi-regional meeting on JE prevention and control in Vientiane Laos. To build regional laboratory capacity for JE testing, three regional hands-on training workshops were organized in 2009, 2010 and 2011. The Papua New Guinea laboratory, which was the last of 10 laboratories to join the regional network, participated in the second hands-on training workshop in 2010.
Three JE network laboratories in the Region use their own in-house assays, China CDC uses locally produced JE kits, and the six remaining network laboratories use the Panbio JE/Dengue IgM Combo ELISA kits. For quality assurance of the JE laboratory network, annual proficiency tests for JE were successfully conducted in 2009, 2010 and 2011, and a confirmatory testing mechanism was also established in the Region. The WHO accreditation programme, which uses the WHO JE laboratory checklist, was initiated in 2010. Eight out of 10 laboratories have been accredited as of September 2012.