As Japan faces a super-aging society, one of the urgent issues to be addressed is hearing loss, which not only reduces the quality of life and productivity in daily life but can also be a factor in the onset of dementia. Despite these dangers, the rate of hearing aid use, which is an effective countermeasure for hearing loss, is significantly lower in Japan（14％）than the EU countries and the U.S.（30 ～ 40％）. Therefore, there is much room for improvement in Japan to gain widespread use of hearing aids. Generally, a hearing aids have been recognized as one of the welfare devices for the hearing impaired, and there has been little discussion among scholars from the perspective of distribution and business. In developed countries in the EU and the U.S., the number of people who wear hearing aids is expanding due to the expectation that hearing aids will help prevent the onset of dementia in addition to the technological innovations that have improved the function of hearing aids. Therefore, the innovative trends in technology in the hearing aid business is changing the current business model. 99％ of the world's hearing aids are manufactured by European and American manufacturers and imported hearing aids account for more than 70％ of the market share in Japan, it is expected that global changes in the hearing aid business will significantly impact on the Japanese market.

This study focuses on the Japanese hearing aid business comparing with eight European Union countries and U.S., which has not been discussed so far. This study also examines the status analysis, issues, and prospects of the business model of the Japanese hearing aid industry, which is expected to expand in scale in the future.

It is probable that following hospital strategies have effects on financial conditions in hospitals: 1）strategy relating to roles of hospital in local community as emergency hospital, 2）strategy relating to roles of hospital in local community as home care support hospital, 3）strategy relating to investment on expensive medical equipment, 4）strategy relating to ward management. Therefore, it is important especially for private hospitals operated by medical corporation to have evidence relating to financial impacts by these hospital strategies. It is also important for government departments taking care of medical-fees revision and/or hospital management support to understand financial impacts by these strategies. However, in the past, financial effects by these strategies have not been verified. Therefore, this study tries to verify effects by these strategies on financial conditions in medical corporations with one hospital only. This study verifies effects on many aspects of financial conditions such as profitability, total asset turnover and return on asset. Regression model is used to verify financial effects by these strategies（explanatory variables）controlling many other variables effecting on financial conditions such as corporate economic scale（control variables）. This study verified effects by strategies for two years under two different systems of medical and nursing care fee（pre- and post- integrated revision of medial and nursing care fees）. By verifications for these two years, this study tries to confirm consistencies of financial effects by strategies.

The COVID-19 pandemic has had a major impact on the approach to global surveillance of infectious diseases. In this paper, among the currently operating surveillance systems in Japan, we focus on the national epidemiological surveillance of infectious diseases（NESID）system and the active epidemiological investigation scheme, both of which operate based the Infectious Diseases Control Law in Japan. This paper also discusses the response to the current pandemic and the future of infectious disease surveillance.