Infectious have plagued humans since ancient era. Infection is often the direct cause of mortality especially in elderly population. Management of infectious diseases is very important for physicians in Japan, which rate of elderly has become higher than other countries rapidly. There are some clues to manage infectious diseases in the elderly. 1) Afebrile does not mean non-infectious cause. 2) Have to check the difference from everyday life. 3) Perform a physical examination carefully. 4) Do not use broad spectrum antibiotics just because of the patients’ age. 5) Do not forget tuberculosis. 6) Prevent infectious diseases as much as possible. These clues must be helpful for physicians when they manage infectious diseases in the elderly.
