Recent progress and concerns regarding the Japanese immunization program: addressing the "vaccine gap".

Recent progress in the Japanese immunization program has partially closed the "vaccine gap," i.e., the deficiencies in that program relative to immunization programs in other developed countries. During the last several years, seven new vaccines (12 new products, excluding influenza vaccines) have been introduced in Japan. Five of these new vaccines are produced outside Japan and four are now included as routine vaccines in the National Immunization Program, which is a new development in the licensing and financial support of imported vaccines. However, along with this progress, important concerns have arisen regarding the Japanese immunization program. A rubella epidemic among adults, in 2012-2013, resulted in more than 40 cases of congenital rubella syndrome as of March 2014. In addition, the temporary withdrawal of the active governmental recommendation for human papilloma virus vaccines, in 2013-2014, highlighted challenges in the current Japanese immunization system. Furthermore, some important vaccines - including vaccines for hepatitis B virus, mumps, varicella, and rotavirus - are still not included in the National Immunization Program and have been categorized as voluntary vaccines since their introduction. The possibility of their inclusion in the National Immunization Program remains a matter for discussion. We hope that future initiatives will further address the vaccine gap and protect Japanese children from vaccine-preventable diseases.