AIDS in the United States is rising faster among women than men, scientists say.

The U.S. Centers for Disease Control projected that by next year AIDS would be the nation's fifth leading cause of death among American women of childbearing age. It is now sixth or seventh, according to the CDC.Separately, the World Health Organization predicted a dramatic increase in the infection rate among women worldwide by the end of the century.

Both studies were released Thursday.

"I think these findings are a cause for alarm for almost everyone," said Dr. Constance Wofsy, a professor of clinical medicine and an AIDS specialist at the University of California at San Francisco.

AIDS still occurs mostly among homosexual men and intravenous drug users.

Women are most likely to become infected through sex with men who carry the virus.

Such women rarely suspect they are at risk and often fail to take precautions, Wofsy said. Symptoms that would alert doctors to test for AIDS in a homosexual do not set off the same "red light" in women, Wofsy said.

"Physicians are going to have to become detectives," she said.

The Atlanta-based CDC said in its weekly report that by the end of the year, AIDS cases among U.S. women would exceed 15,000, about 11 percent of all reported cases More than 9,000 of those women will be dead by then, it said.

In the last year, the AIDS rate rose 29 percent among women and 18 percent among men, the agency said.

Currently, cancer is the No. 1 killer of women between 15 and 44, followed by accidental deaths, heart disease, homicide and suicide, the CDC said.

Seventy-two percent of the American women stricken with AIDS are black or Hispanic.