A good collection of links to information on respiratory tract diseases, such as asthma, infections, lung diseases and nose and throat problems. Site is an Australian government initiative, so some references may not be totally relevant.
"Medscape offers specialists, primary care physicians, and other health professionals integrated medical information and educational tools. After free registration, Medscape delivers the specialty site that best fits your profile."
The National Institute of Allergy and Infectious Diseases (NIAID) conducts and supports basic and applied research to better understand, treat, and ultimately prevent infectious, immunologic, and allergic diseases.
"An award-winning Federal Web site for consumers, developed by the U.S. Department of Health and Human Services together with other Federal agencies. It links to carefully selected information and Web sites from over 1,500 health-related organizations."