New studies adds fuel to circumcision debate
Does circumcision reduce the risk of HIV transmission, or is it the religious practices of individuals who are circumcised that shows its effects in lower rates of HIV in these communities?
That debate has been argued for years. Epidemiologic evidence suggests that circumcision may have something to do with transmission, and now researchers in Chicago suggest there is a biological explanation as well.
`‘We determined that the target cells that HIV infect are found in far greater numbers in the foreskin than in the cervix,’’ said Dr. Carlos Estrada, MD, a researcher at Rush-Presbyterian-St. Luke's Medical Center, Chicago. In presenting his study at the 97th American Urological Association in Orlando, Florida (May 2002)  Estrada said ‘‘We think that our findings may show that the reason populations in Africa where Islam is practiced have lower HIV infections rates than in areas where circumcision is not practiced may be biological rather than faith-based.’'
Circumcision is routinely performed after birth in the United States and is proscribed for males by Jewish and Muslim religious law. Several studies have shown that in African nations where Islam is widely practiced, rates of HIV infection can be one-tenth of some countries in southern Africa where circumcision is not generally practiced.
Some researchers have argued that the reduction in rates has nothing to due with the operation, but has everything to do with religious requirements for general cleanliness and monogamy. Social commenters, however, have suggested that even in areas when Islam is practiced, adherence to religious prohibitions against sex outside of marriage are obeyed – or not obeyed – similarly to other religions’ taboos against extramarital relationships. A symposium was dedicated to the pros and cons of circumcision at the Durban World AIDS Conference in 2000.
In the study by Estrada and colleagues CD4 T cells, macrophages and Langerhans’ cells – cells that are targets for HIV – were found in high proportion in foreskin tissue compared to human cervical cells. ‘‘The highest proportions of these cells were found in the adult foreskins,’’ Estrada said. Those tissues, he explained, contained cells that expressed predominantly a co-receptor required by HIV to infect cells.
`‘Overall, the inner, mucosal surface of the foreskin had a seven-fold greater susceptibility to HIV infection than did cells in cervical tissue infected under the same conditions’’ he said. ‘‘The issue here is that epidemiologic data strongly suggests that circumcision protects against HIV,’’ said Dr. John Krieger, MD, professor of urology at the University of Washington, Seattle. ‘‘These authors looked at pediatric and adult foreskins. What they found was that foreskins have a lot of HIV target cells. So the increased risk of HIV infection in uncircumcised men is likely caused by large numbers of target cells in the foreskin. Circumcision is biologically plausible as a way to reduce HIV infection risk.’'
However, others were not ready to accept that theory. Dr. Thomas Brady, MD, adjunct professor of urology at the University of Nevada-Reno, and chairman of the media committee of the American Urological Association said ‘‘Just because there are more of these cells doesn't mean that there is a greater transmission risk.’'
Web sites of interest
Journal of Urology: http://www.jurology.com American Urological Association: http://www.auanet.org
1 Estrada et al. Biologic mechanisms of HIV infection of human foreskin: Implications for transmission.J Urol147 (Suppl 4): 2002 [abstract 111].
Notes from the XIV International AIDS Conference in Barcelona, Spain
United Nations officials predicted that in the next 18 years 68 million people will die from AIDS in the most affected nations in the world – five times the number of people already killed by the worldwide epidemic.
Twenty years since first identified as a health threat, doctors said the epidemic – despite already having killed 22 million people worldwide and infecting an additional 40 million men, women and children – is still in its early stages. ‘‘Effective responses to this epidemic are possible,’’ said Dr. Pete Piot, executive director of the Joint United National Programme on HIV/AIDS (UNAIDS), ‘‘but only when they are politically backed and full scale, and that unless more is done today and tomorrow, the epidemic will continue to grow.’’ The report describes a litany of bad news as surveillance of infection with HIV shows that in southern Africa, about 40% of pregnant women ware infected with HIV; In Botswana, where 36% of adults were infected with HIV 2 years ago, the rate continues to rise to 39% in 2001; In West Africa, an apparent stability in the prevalence of HIV infection has turned around – in the wrong direction as rates in the single digits have leapt into double digits; belief that major Asian populations would be free of the epidemic have been shattered with rising infections in Indonesia and China; hopes that the epidemic would be confined to marginalized segments of the drug injecting populations of Eastern Europe and Central Asia have proved illusory as the epidemic is spreading into heterosexual populations.
Report on the global HIV/AIDS. Geneva: UNAIDS; 2002.
Thailand: care of children born to HIV-infected mothers
Researchers from Thailand's Ministry of Public Health and the US Centers for Disease Control and Prevention (CDC) said that more than 90% of children born to HIV-infected mothers received short-course treatment of zidovudine in a Thai-wide effort to show that developing countries can deliver antiretroviral therapy to its citizens. ‘‘The level of success achieved by this program represents a major victory in Thailand's effort to reduce the devastating impact of HIV on our children,’’ said Pornsinee Amornwichet of the Thai Ministry of Public Health, and lead author of a study in the Journal of the American Medical Association (JAMA). The report was released in a JAMA-sponsored press briefing held in conjunction with the XIV International AIDS Conference. In the program, Thai officials said that 97% of the 573 655 women who gave birth in the country from October 2000 through September 2001 received prenatal care. The health officials identified 6646 HIV-infected pregnant women among that cohort. About 69% of these women were treated with zidovudine. Of the 6475 babies born to those women, 88% – or 5682 – were treated with zidovudine.
Amornwichet P et al., Preventing Mother-to-child HIV transmission.JAMA 2002, 288: 245–248.
HIV resistant strains
About one in seven people who have recently been infected with the virus that causes AIDS have contracted a strain of the organism that is already resistant to drugs used to treat the infection, doctors said. ‘‘This research has to put into question widely-held assumptions that infection with human immunodeficiency virus can be easily treated with available drugs,’’ said Dr. Frederick Hecht, associate clinical professor of medicine at the University of California, San Francisco. He said that people who engage in high-risk unsafe sexual practices could become infected with strains of the disease that mean they would no longer be available for standard first-line treatment. ‘‘We are seeing some patients who may need to begin therapy with salvage regimens,’’ Hecht said at a press briefing discussing new research in the Journal of the American Medical Association (JAMA), held in conjunction with the opening of the 14th World AIDS Conference. In his study, Hecht analyzed the virus that infected 225 patients in San Francisco who showed signs of having been newly infected with HIV. He looked at the genetic makeup of the virus in three groups of patients – 80% of whom were men: those infected in 1996–1997; those infected in 1998–1999 and those infected in 2000–2001. While just 1 or 2% of patients were infected with strains resistant to two classes of drugs in the early time periods, 13.2% of patients in the last group had resistant viruses, Hecht said.
Grant R. Time trends in primary HIV-1 drug resistance among recently infected persons.JAMA 2002, 288: 181–188.
USA HIV infection rates
Every 3 months about 10 000 people in the USA are newly-infected with HIV — a level that has remained about constant since 1998, said government officials said at the conference. However, doctors from the Centers for Disease Control and Prevention in Atlanta, Georgia, said they are seeing troubling signs that might mean the epidemic may rise once again. Overall, an estimated 800 000–900 000 people in the USA are infected with HIV, the incurable organism that destroys a person's immune system and eventually allows development of deadly infections, researchers said. Among the signs that worry epidemiologists, said Dr. Ron Valdiserri, deputy director of the CDC's National Center for HIV, STD, and TB Prevention, include outbreaks of the STD among men who have sex with men in several cities in the USA – including Seattle, San Francisco, Los Angeles, Houston, Chicago, New York City, Washington and Miami. ‘‘While many of these men are already infected with HIV,’’ Valdiserri suggested that a rise in these infections may be a prelude to new HIV infections. ‘‘We have seen the rate of syphilis increase from about 2.2 per 100 000 in men in New York City in 1996 to 6.9 per 100 000 in 2001,’’ he said, ‘‘and most of those infections are occurring in men who have sex with men.’'
Global reduction in life expectancy
In 51 countries, life expectancy – the average number of year a person can expect to live – has decreased as much as 30 years due to the impact of AIDS, researchers reported at the International AIDS Conference. US Census Bureau researchers said their analyses found that life expectancy is less than 40 years in seven African nations – levels not seen since the 1800s. ‘‘In 2002 the life expectancy of a person living in Botswana is 39 years, when without the AIDS impact the life expectancy in that African country would be 72 years,’’ said Karen Stanecki, chief of the health Studies Branch of the Bureau of the Census, Washington DC. And, she said, the situation will get worse by the end of the decade. By 2010, she said, life expectancy will be just 27 years for a person in Botswana, compared to 74.4 years if the AIDS epidemic did not exist. In Bostwana 39% of adults are infected with HIV, the organism that causes AIDS. Stanecki said that the loss of life expectancy occurs because AIDS kills people in mid-life and it kills infants and children before they reach the age of 5 years, reducing the average years a person lives. ‘‘In 2010, 80% of the deaths of children under the age of 5 in Botswana will be due to AIDS,’’ she said. ‘‘By 2010 more children in Botswana, Swaziland, Zimbabwe, Namibia and South Africa will die from AIDS than because of any other cause.’'