Influenza vaccination coverage in Japan

Sir

Vaccination is the main method used to prevent influenza. In the USA, 33% of the population aged older than 65 years were vaccinated in 1989 compared with 64% in 2000–01.¹ One of the objectives of Healthy People 2010 is to achieve a vaccination coverage in the USA of 90% in this age-group.

From 1976 to 1994, influenza was listed in the Japanese Preventive Vaccination Law, which stated that all children aged 7–15 years had to be vaccinated against the disease. The law was, hence, meant to control influenza epidemics in entire communities via suppression of transmission in schools. However, in 1979, a 7-year-old child fell ill after receipt of the vaccine. This event along with adverse data reported with respect to the preventive effects of vaccination, made many people suspicious of the vaccine's effectiveness.² Vaccination became voluntary after a 1994 amendment to the Preventive Vaccination Law.

However, in 1998–99, an influenza epidemic in Japan resulted in the deaths of about 250 elderly residents of nursing homes, resulting in recognition by the government of the need to vaccinate at least the frail elderly population. The Law was, therefore, amended again in November, 2001. Under the new Preventive Vaccination Law, primary target groups are defined as those aged older than 65 years and those with certain chronic medical conditions who are aged 60–65 years. The degree of subsidy for the cost of vaccination is worked out independently by each local government.

The number of influenza vaccines produced in Japan rose greatly from 300 000 in 1994 to more than 10 million in 2001, but only 27% of the target population in Japan were vaccinated in 2001–02.³ The amount of vaccines produced continued to increase to 13 million in 2002 and 14·5 million in 2003. Because the Ministry of Health, Labor, and Welfare predicts demand to be 12.4–14 million in 2003–04, little effort is being made to raise the vaccination rate in target populations. However, we believe this increase in the production of vaccines and rate of coverage of target populations is insufficient, bearing in mind the rapid growth rate of the elderly population. Moreover, individuals who live with or care for people at high risk, and children, should be vaccinated—the total number of patients with influenza rose from 306 000 in 2000–01 to 675 000 in 2001–02; 58% of all patients were children aged 0–9 years.

In the USA, increasing the number of people vaccinated against influenza depends on greater acceptance of preventive medical services by practitioners, increased delivery and administration of the vaccine by health-care providers and sources other than doctors, and provision of new information with respect to the effectiveness, cost-effectiveness, and safety of the vaccine. Since Japan lags behind the USA and other countries with respect to vaccination coverage, a national policy to increase uptake should be developed.

In 2003, severe acute respiratory syndrome (SARS) was pandemic, and in the coming winter, people, including providers, will seek influenza vaccination to avoid any confusion with SARS. There could be a panic if influenza becomes epidemic and the amount of vaccine is inadequate. Now is the time to reconsider a comprehensive strategy to promote influenza vaccination in Japan.