From 1998 to 2001, using questionnaires, we surveyed the use of travel vaccines among Japanese expatriates in developing countries. The percentage of those using more than one type of travel vaccine before departure increased significantly (45.6% in 1998 to 53.4% in 2001 (p<0.001)). In regions such as tropical Africa and South Asia, vaccination rates were high. But the increase was most noticeable in East Asia, the Middle East, and Latin America. Vaccinations against hepatitis A, hepatitis B, and tetanus were high throughout the developing countries. Vaccinations against yellow fever and Japanese encephalitis were high in endemic regions. Vaccination rates were slightly higher for typhoid fever in South Asia and tropical Africa than that in other areas. Vaccination rates for cholera, however, showed yearly declines. These trends seem to reflect a growing awareness among expatriates of the benefits of travel vaccines. Even so, nearly half of those living the countries have not received sufficient vaccination, indicating a need for further education.

We gathered and analyzed date on respiratory diseases suffered by Japanese adults treated in Ram Hospital in Chiang Mai and Subang Jaya Medical Center in Kuala Lumpur. In both hospitals, the percentages of patients undergoing treatment for respiratory diseases was the greatest. Of these, relatively mild symptoms such as upper respiratory tract infection account for the majority of the diseases, but also included are instances of lower respiratory tract infection or chronic respiratory diseases such as chronic sinusitis and COPD⁄bronchial asthma. In Kuala Lumpur, we conducted a questionnaire-based survey targeted on Japanese people living there, in order to detemine the currnt status of respiratory deseases. The date showed that many Japanese had symptoms of respiratory diseases and felt that air pollution was serious.
It is important for Japanese people living in Asia to be aware of preventative measures to prevent respiratory diseases, such as those caused by air pollution and infection.