New evidence that drugs prevent HIV infection after rape
New research provides direct evidence that anti-retroviral drugs can prevent HIV infection after sexual intercourse. This research comes amid a series of controversial decisions regarding the provision of AZT to rape victims in South Africa. The new national guidelines for HIV care launched on Tuesday (24th October) deny the use of anti-retroviral drugs to rape survivors but the Western Cape will provide AZT to rape survivors nonetheless. Jo Stein reports.
Trials conducted on laboratory animals in the United States have found that the provision of anti-AIDS drugs soon after sexual intercourse can prevent HIV infection.
This latest evidence could strengthen the Western Cape Health Department’s case for providing AZT to rape survivors, a move that has been slammed by the African National Congress.
The research, published in the Journal of Virology, a highly regarded international publication, was conducted on pig-tailed macaques.
Not one of the monkeys that were vaginally exposed to the HI virus and treated with an anti-retroviral drug within 36 hours, became infected.
But 75 percent of the monkeys who were not given drugs were infected with the HI virus.
Until this study, there was no direct scientific proof that anti-retroviral drugs such as AZT could prevent HIV transmission after sexual intercourse, including rape.
The decision to provide AZT to rape survivors in the Western Cape was based on the fact that anti-retrovirals reduced HIV infection by two-thirds in babies and by more than 80 percent in needle-stick injuries, according to Dr Jane Yeats, a specialist at the University of Cape Town’s Department of Virology.
“So one would logically expect that anti-retrovirals after rape would reduce infection by a similar amount,” says Yeats, who is also a member of the Western Cape health department’s task team on supplying AZT to rape survivors.
Although only 16 monkeys were vaginally infected with HIV in the US trials, the results of the study are still considered to be scientifically valid.
“75% versus 0% is a big enough difference despite the small numbers. There is no need to use more monkeys. These are primates we are injecting with HIV, not mice,” says Yeats.
The USA research was conducted by a team of scientists from the Centres for Disease Control and Prevention in Atlanta.
President Thabo Mbeki justified the refusal to give AZT to rape victims on the grounds that “AZT is not registered by Glaxo-Wellcome for use as prophylaxis in rape” in parliament earlier this year.
Manufacturers of AZT, Glaxo Wellcome, said the new research would not make it possible for the company to register AZT for use with rape survivors because the study was not conducted on humans for ethical reasons.
Medical ethics dictate that it is unethical to give a drug that one presumes is effective to certain women who have been raped, but to deny it to others in the interests of medical research.
But the fact that AZT cannot yet be registered for use with rape survivors does not prevent doctors from legitimately using it for this purpose, said Glaxo Wellcome spokesperson, Vicki Ehrich. In clinical practice, many drugs are used for indications for which they are not technically registered.
Professor Gary Maartens from the Infectious Diseases Unit at UCT said the lack of registration of the drug for use in rape is also not a valid reason for the national Department of Health to delay the provision of AZT to rape victims.
“AZT was in widespread use on a national level for needle-stick injuries for at least five years before we had enough scientific evidence for it to be registered,” says Maartens, who also heads the Western Cape task team on supplying AZT to rape survivors.
The drug misoprostol is also not registered for use in abortion by Searle, but is used for this purpose in state hospitals.
Special advisor to the Minister of Health, Ray Mabope, said that the Department of Health “will consider any new work showing that post-exposure prophylaxis is useful in issues of rape, within the context of other literature on the subject.”
The latest research findings come amid a series of controversial decisions regarding the provision of AZT to rape victims.
The new national guidelines for HIV care issued on Tuesday (24th October) by national health minister Manto Tshabalala-Msimang denies the use of anti-retroviral drugs such as AZT to both pregnant women and rape survivors on the grounds that they are both toxic and expensive.
The Mpumalanga Health Department, in line with national government policy, recently ordered the Greater Nelspruit Rape Intervention Project (Grip), a non-governmental organisation, to stop supplying AZT to rape survivors.
But the Western Cape health department has budgeted for between 3 000 and 4 000 AZT treatments at public health facilities for rape survivors annually. About R2- million a year has been earmarked for this purpose.
It is expected that rape survivors are at greater risk of HIV infection than other women because there is a higher incidence of vaginal tearing and bleeding during rape than during consensual intercourse. ‘ Health-e news service.