Women who are fed up with their partners not wearing condoms during sex may soon
have a new tool to protect themselves against HIV infection.
Scientists at the University of Utah have created a gel that women can apply
internally that works as a “molecular condom” to block the virus from entering
the vagina. Their findings were published online yesterday in the journal
Advanced Functional Materials.
The distribution of this gel could greatly reduce the transmission of HIV in
both developing and developed countries, while offering women a discreet way to
take control of their sexual health.
Patrick Kiser, an assistant professor of bioengineering at the University of
Utah, worked with a team of scientists to develop a gel that has a slightly
acidic pH level, similar to that of the vagina. When the gel comes in contact
with semen – which has a more neutral pH level, much like water – it is
“activated,” Dr. Kiser said. “The gel changes its structure and it becomes more
difficult for the virus to move through [it],” he said.
At Toronto's Hassle Free Clinic, the first site in Canada to offer anonymous
testing for HIV, sexual-health counsellor Jane Greer has high hopes for this
HIV-blocking gel. “We've been talking about microbicides in our line of work as
the holy grail for years,” she said.
Research into developing a microbicide (gels, rings and films to kill
micro-organisms that are inserted in the vagina or the rectum) took off in the
mid-1990s, but scientists have stumbled over funding clinical trials or just
coming up with a product that works effectively. Some prototypes increased the
risk of HIV transmission, Dr. Kiser said.
At
this point, the gel's effectiveness has been studied only under a microscope,
but Dr. Kiser's team hopes to complete a clinical trial in the next three to
five years. He said the gel could also probably be used to protect against
herpes and human papillomavirus (HPV) as well as to prevent pregnancy, though it
has yet to be tested for its effectiveness in those areas.
For now, the only way women can protect themselves against HIV transmission is
by using a female condom. Tests suggest that it is at least as effective as the
male condom – the use of which reduces the risk of HIV transmission by 80 per
cent – but because part of it sits outside the vagina, Ms. Greer said, it's not
popular with women. “I've heard it described as having sex with a plastic bag in
you, so it's not ideal,” she said.
Another problem is accessibility. Public-health units invest far more in male
condoms than female ones for distribution at sexual-health clinics, Ms. Greer
said.
In 2005, the United Nations reported that the cost to produce a male condom was
three cents (U.S.), while a female condom was 60 cents. Dr. Kiser said the
“molecular condom” should cost no more than five cents to produce each dose,
with a shelf price comparable to male condoms.
“If you're talking about impacting the HIV/AIDS pandemic, you're really
concerned about engineering technologies that are … extremely inexpensive and
simple that can be used in the developing world,” he said.
While developing countries – particularly those in sub-Saharan Africa – have the
world's highest rates of HIV/AIDS, Ms. Greer said the gel has the potential to
dramatically cut the rates of infection in Canada.
In 2006, the Public Health Agency of Canada estimated that 20 per cent of people
living with HIV were women. The primary way the virus is transmitted to this
population is through heterosexual sex.
Ms. Greer said a microbicide would be particularly useful for women from the
aboriginal, African and Caribbean communities, who experience higher rates of
HIV than the rest of the population. Women could protect themselves without
their partner even knowing, she said, though she recommends that women always
have conversations with their partners about protection before sex.
