Emergency Medical Services Systems and Health Information and Promotion Extensions of 1979 - Amends the Public Health Service Act to extend through fiscal year 1982 the authorization of appropriations for: (1) emergency medical services systems; (2) health information and promotion; and (3) immunization programs. Authorizes the Secretary of Health, Education, and Welfare to defer for an additional year (beyond the current three-year limit for such deferment) the date used with respect to service requirements for National Health Service Corps scholarships for students of medicine, osteopathy, or dentistry. Eliminates the grant set-aside for dentistry training. Repeals: (1) the comprehensive health planning program (which was superseded by title XV, the National Health Planning and Development Act); (2) the provision of title XV which gives priority for designation of health service areas which formerly had an area wide Comprehensive Health Planning Agency; and (3) title IX of the Public Health Service Act (Education, Research, Training, and Demonstrations in the Fields of Heart Disease, Cancer, Stroke, Kidney Disease, and Other Related Diseases). Amends title XIII of such Act (Health Maintenance Organizations) to eliminate the provision which allows an entity which provides prepaid health services and has members eligible for service under Medicare, Medicaid, and the Federal employees' health insurance program to be treated as HMOs for purposes of receiving assistance under such title.