Since 1983, war in Nicaragua has slowed improvements in health which had developed rapidly from 1979-82. The rate of war-related deaths among Nicaraguans now exceeds that of the United States citizens in either the Vietnam War or World War II. Forty-two of the 84 documented war-related casualties among Nicaraguan health workers have been deaths. This high case fatality rate reflects the targeting of health workers by contra troops. The number of staff and services of the public medical system decreased by approximately 10 per cent from 1983 to 1985. Population movements, the establishment of new settlements, and war-related destruction of the primary health infrastructure are associated with recent epidemics of malaria, dengue, measles, and leishmaniasis. The estimated rate of infant mortality in Nicaragua, which had declined from 120 per 1,000 in 1978 to 76/1,000 live births in 1983, has since shown no further decline. Internationally mandated protections enjoyed by civilians and health workers during times of war do not appear to operate in this so-called "low intensity" conflict. Further declines in infant mortality, prevention of epidemics, and improvement in other health indicators will likely await the cessation of military hostilities.