New Heterosexual AIDS Risks Suggested
Women who use birth control pills and men who are not circumcised may be at increased risk of contracting the AIDS virus through heterosexual intercourse, a leading American authority on sexually transmitted diseases reported Thursday.
The physician, Dr. King K. Holmes of Harborview Medical Center in Seattle, also said that the control of an even more important risk factor--open genital sores caused by venereal diseases--has become the key to preventing heterosexual transmission of the virus.
Calls Data ‘Significant’
Holmes said the provocative, new data on circumcision and birth control pills appears “significant” but should be interpreted “cautiously” until further studies are completed.
In a major address on the closing day of the fourth international conference on AIDS, Holmes provided a detailed summation of current knowledge on heterosexual transmission of the human immunodeficiency virus.
Public health programs that fail to focus on potential “high frequency heterosexual transmitters” are “blueprints for disaster,” Holmes said. “Control of genital ulcer disease should clearly receive the highest priority for AIDS control in all countries.”
“This is a new theme,” said Dr. Paul Volberding of San Francisco General Hospital, the president-elect of the newly formed International AIDS Society.
Data presented at the conference indicated that in some African nations, sex with prostitutes is the “single most important factor” in HIV transmission, the University of Washington researcher said.
Recent data also shows that heterosexual HIV transmission is becoming gradually more frequent in the United States, where it now accounts for about 25% of AIDS cases in women and 0.7% of cases in men, according to the U.S. Centers for Disease Control. Reports from inner city areas of Baltimore and Miami now show it may account for up to 5% of all HIV infections.
The researcher’s list of the most significant factors favoring heterosexual HIV infection included genital sores caused by such germs as syphilis, chancroid and herpes, chlamydia infections in women, anal intercourse and failure to use a condom.
Some More Infectious
Individuals with AIDS or on the verge of progressing to AIDS also appear to be more infectious than asymptomatic individuals because they tend to have more HIV in their bloodstream, according to Dr. Robert Redfield of the Walter Reed Institute of Research in Washington.
But in the absence of such risk factors, frequent sexual relations with an infected partner do not appear to increase the likelihood of HIV transmission compared to infrequent sexual relations, Holmes said.
The researcher also cited the new findings suggesting that birth control use and lack of circumcision may now need to be added to the risk factor list.
This circumcision data comes from separate studies in Nairobi, Kenya, and Miami of female-to-male transmission of the virus. Both of the studies were presented for the first time at this week’s AIDS conference.
The Miami study involved 92 couples; one member of each was infected with HIV. The University of Miami team, led by Dr. Marcaret Fischl, found that the risk of infection was significantly related to lack of circumcision. It was also related to failure to use condoms, herpes sores and the amount of HIV in the circulation.
The Nairobi study was performed by an international team including University of Washington-Harborview researchers and scientists from Belgium, Canada and Kenya.
The study involved 291 men who frequented prostitutes. Nearly all--98%--of the 23 HIV infections occurred in men who had either open sores on their penises or no circumcision.
Could Conceal Sores
Holmes said that lack of circumcision could increase a man’s risk of HIV transmission by, for example, concealing small sores or areas of inflammation.
The birth control pill data comes from a related study of 123 Nairobi prostitutes by the same international research team. Among the 83 women who developed HIV infections during the 50-month study, there was a “very significant” excess of those who had genital ulcers, chlamydia infections (the most common sexually transmitted disease in the United States, which causes inflammation of the cervix and the pelvic organs in women) or used oral contraceptives, Holmes said. The risk of infection was significantly decreased in the prostitutes who used condoms.
Holmes said the birth control pill data needed to be “interpreted with caution.”
