Current problems of measles control in Japan and Western Pacific Region.

Measles is still the leading cause of childhood death and is a vaccine-preventable disease globally. Even countries in which measles had been eradicated still remain at risk of importation from countries that have not yet eliminated the disease. Although two dose of immunization program with combined measles and rubella (MR) vaccine has been started since April 2006, there are still estimated 5-10 thousands measles cases annually in Japan. We introduced the Vero/hSLAM cell line for routine isolation of wild measles viruses in the WHO laboratory network. Vero/hSLAM cells express both CD46 and SLAM receptors and are highly sensitive to both vaccine and wild measles virus strains. Although Vero/hSLAM cell lines require an expensive antibiotics (G418) to maintain the transfection necessary for expression of the human SLAM receptor, we are trying to establish more simple, rapid and reliable diagnostic assays for measles virus infection.