Report Sees HIV Rise in Hemisphere : Epidemic: The World Health Organization warns of an AIDS surge in Central and South America.

More than 3 million people in the Western Hemisphere will be infected with the AIDS virus by the mid-1990s, largely because the epidemic is spreading rapidly in Latin America, the World Health Organization said in a report to be released today.

The rate of infection appears to be slowing in North America, where about 1 million people have been stricken with the human immunodeficiency virus, or HIV. The number infected in Latin American and Caribbean countries, currently about 1 million, is expected to double in five years, the health organization said.

WHO previously estimated that HIV infections might strike 20 million people worldwide by the end of the century, with 90% of the cases developing in Third World countries.

Hiroshi Nakajima, director-general of WHO, said that efforts to contain the virus that causes acquired immune deficiency syndrome, or AIDS, must be started immediately in the Western Hemisphere.

“Judging from the explosive spread of HIV infection in sub-Saharan Africa, now is the time to marshal all available resources to curb the AIDS epidemic in Latin America and the Caribbean,” Nakajima said in a statement.

Of the estimated 2 million people in the Western Hemisphere already infected with HIV, about 500,000 have developed AIDS. HIV infects and severely weakens the human immune system. When symptoms appear, the HIV infection is considered to have advanced into AIDS.

In the Western Hemisphere, infections from the deadly virus are found mainly in and around cities. The incidence of infection remains low in rural areas, according to the report.

Dr. Ann Marie Kimball of the Pan American Health Organization, a branch of WHO, said that even in Latin America, where infection rates are climbing, the per-capita incidence of the AIDS virus is “quite a bit lower” than in the United States, where 0.4 % of the population is believed to be affected.

She expressed optimism that efforts to promote “safe sex” practices, to reduce intravenous use of drugs and protect blood supplies could slow the spiraling infection rate in Latin America. But many nations need financial assistance to support such efforts, she said.

HIV usually is spread via sexual or blood-to-blood contact, such as by drug users sharing contaminated needles. The deadly virus also can be transmitted from a pregnant woman to her unborn child.

WHO said that in some U.S. and Canadian cities, as well as parts of the Caribbean, AIDS is the leading cause of death among males ages 25 to 34. And, although official figures indicate that about 113,000 people have died of AIDS in this hemisphere, the actual number may be twice that, the study said.

In the United States, the Centers for Disease Control estimates that 164,129 people have developed AIDS and 102,803 of them have died.

One in 10 pregnant women in Haiti is believed to be infected, and HIV in pregnant women is on the rise elsewhere in the Caribbean and in Brazil, WHO said.