Federal officials have painted an appalling vision of the spread of the virus that causes AIDS through sub-Saharan Africa, saying that by the year 2015 the disease could double the death rate among women, wipe out up to a third of able-bodied men in some ethnic groups, and create perhaps 16 million orphans.

The new projection Saturday by an arm of the U.S. Census Bureau says the ravages of AIDS are reversing hard-won victories against infant and child mortality from other causes, such as diarrhea and measles.

The U.S. predictions are based on a mathematical model projecting the spread of AIDS in Africa over the next 25 years. By 2015 the disease is projected to reduce life expectancy in urban areas of sub-Saharan Africa by 19 years, said officials at a meeting of the American Association for the Advancement of Science.

"This epidemic is going to cause many emergencies, and one of them is going to be caused by the numbers of children who don't have homes," said Linda A. Valleroy, an epidemiologist with the Census Bureau and the U.S. Agency for International Development.

Already in Tanzania, Valleroy said, children have a one-in-three chance of being infected with the virus at birth.