In 1995, an estimated 500,000–800,000 Rwandan refugees fled to neighboring Zaire (now the Democratic Republic of the Congo). Almost 50,000 died during the first month after the exodus, many of diarrheal diseases. In normal times, malnutrition is the greatest health problem in Rwanda. Animal proteins and fats are scarce. Kwashiorkor, a protein-calorie deficiency, is common, contributing to the death of many children and to liver trouble in older individuals; it also increases the severity of other prevalent diseases, among them pneumonia, tuberculosis, measles, whooping cough, and dysentery. Malaria and trypanosomiasis (sleeping sickness) are endemic. In a 1987 study, Kigali was reported to have one of the world's highest rates of infection with the AIDS virus; Rwandan Red Cross figures showed that between 10% and 15% of blood collected was contaminated with the virus. There were 10,706 AIDS cases reported in Rwanda during 1996. At the end of 2001, the number of people living with HIV/AIDS was estimated at 500,000 (including 9% of the adult population), and deaths from AIDS that year were estimated at 49,000. HIV prevalence in 1999 was 11.2 per 100 adults.
Poor sanitation measures and water pollution also cause serious health problems; in 2000, 41% of the population had access to safe drinking water and only 8% had adequate sanitation. In 1999, there were about 381 cases of tuberculosis per 100,000 people. Immunization rates for 1997 for children up to one year of age included diphtheria, pertussis, and tetanus, 77% and measles, 66%. There were 5,999 cases of measles in 1994.
As of 1999, it was estimated that there were fewer than 0.05 physicians and 1.7 hospital beds per 1,000 people. As of 1999, total health care expenditure was estimated at 4.1% of GDP. The World Health Organization, the UN Food and Agriculture Organization, and UNICEF provide aid in public health services. Since the late 1960s, the UN, Belgium, France, and the United States have been assisting Rwanda in specific health-related projects.
As of 2002, the crude birth rate and overall mortality rate were estimated at, respectively, 33.3 and 21.4 per 1,000 people. Average life expectancy in 2000 was 40 years with the infant mortality rate estimated at 123 per 1,000 live births. Maternal mortality was 210 per 100,000 live births in 1991–93. These rates do not include about 2,000 war-related deaths between 1991 and 1992 (Tutsi and Hutu conflict) and over 500,000 deaths in 1994 (mostly of Tutsi civilians by Hutu militias).