Age and Immunity Immunity to disease declines in the elderly. Each bout of disease lowers it further. Much care must be exercised in disease prevention, specially respiratory infections. AIDS AIDS symptoms take about 15 years to appear after infection. Within eight weeks of infection, a positive response to HIV is detected.
Death comes from loss of body's defence against infections, primarily respiratory.
By the end of 1994, there were about four million cases of AIDS world-wide. Air Conditioning Air conditioning removes moisture and dust from air and can be very helpful in many diseases, particularly of respiratory tract. Airconditioning Diseases Air-conditioning can cause diseases. Allow for some fresh air to dilute air-conditioned air. Keep air-conditioner filters clean.