News (Updated October 17, 2004)
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WASHINGTON (Reuters) - A souped-up version of a naturally occurring immune system protein can protect female monkeys from the AIDS virus, scientists have reported in a finding they say may lead to a new way to prevent infection in people.
They hope to eventually use their discovery to develop a microbicide -- a cream or gel that women and men could use to protect themselves from sexual transmission of the deadly virus.
With 43 million people infected and more than 25 million already dead from the incurable virus, a microbicide would be a valuable way to help fight the epidemic.
"The vast majority of HIV infections in the world are sexually transmitted, most commonly through heterosexual sex," said Dr. Michael Lederman of Case Western Reserve University in Cleveland, Ohio, who helped lead the international study.
"But there has been substantial debate as to how the virus actually gets into cells at these sites of transmission, called mucosal sites."
The human immunodeficiency virus that causes AIDS uses molecular doorways called receptors to get into CD4 T-cells, the immune system cells that HIV infects. One of these receptors is called CCR5.
"We knew that people with a mutation whose CD4 cells' surface lack CCR5 are almost completely protected from acquiring HIV infection," Lederman said.
It was also known that an immune system messenger chemical or chemokine called RANTES can attach to CCR5 and keep HIV from getting in.
'A PRETTY HEFTY DOSE'
Robin Offord and Olivier Hartley of the University of Geneva in Switzerland developed a special form of RANTES that did this especially well. The team worked to dissolve their new chemical in saline solution and then tested it to see if it would protect monkeys.
It did, they report in this week's issue of the journal Science.
They put the solution into the vaginas of female rhesus monkeys and 15 minutes later put in a solution containing SHIV, a hybrid of the human HIV and the simian version of the virus that infects monkeys.
The highest dose of PSC-RANTES protected all five monkeys that got it. The second-highest concentration protected four out of five monkeys treated, while a slightly lower concentration protected three of five animals.
"It took a pretty hefty dose to get protection in the rhesus monkeys," Lederman said in an interview. "In reality this is pretty pricey."
But in laboratory tests, the chemical prevented the virus from infecting cells for a full day. That could mean a woman could use a gel or cream 24 hours before having sex and still be protected, in theory at least.
The Swiss team is now working on a cheaper and easier way to make the RANTES molecule.
Lederman said his team wants to test the compound in people. He said it appeared to be safe and did not cause irritation in the monkeys -- something important for a microbicide used in the vagina or anus.
AIDS experts agree that women and some men need an alternative to condoms to protect themselves from the AIDS virus. In many instances women are unable to refuse sex from husbands or other men and, even more commonly, men refuse to use condoms.
Several groups are working to develop microbicides but advocacy groups complain the field is not funded as well as it could be.
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Sat Oct 16, 6:11 PM ET
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ASMARA (AFP) - The AIDS situation in Eritrea is
worrying, but there are reasons to be hopeful, UNAIDS has said.
"The last figures show that the national HIV prevalence rate is 2.4
percent," UNAIDS country programme adviser Dominique Mathiot told AFP
during an interview in Asmara.
"We are worried by this rate because above 1 percent means the epidemic
is generalized. The rate for pregnant women here is above 5 percent and in any
country the HIV prevalence rate can within three years increase from 2% to
12%," he insisted.
But currently, "there seems to be a stabilization of the prevalence,
thanks notably to the government's efforts."
"Free and anonymous AIDS screening has highly increased, and we are
doing prevention campaigns with the armed forces and the UN peacekeeping
soldiers," present in Eritrea, UNAIDS said.
Military service is compulsory in Eritrea.
"What makes me optimistic is that the government's commitment is clear
and precise, and that the work accomplished these last years can continue,"
Mathiot added.
Limited cross-border mobility has also helped to control the spread of HIV
and AIDS. Eritrea's two main borders, with Ethiopia and Sudan, are currently
closed.
"The limited mobility helps control the epidemic's expansion. Some
regions of Ethiopia have prevalence rates which are five to six times higher
than the Eritrean one," Mathiot said.
But "the current isolation will not last forever". If tourism in
Eritrea develops, the epidemic could expand, he said.
Eritrea, a small country in the Horn of Africa, has a population of nearly 4
million people, according to Asmara.
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Tue Oct 12, 1:04 PM ET
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JOHANNESBURG (AFP) - A global online sex survey showed almost 60 percent of South Africans engaged in unprotected sex despite the fact that the country has one of the highest AIDS rates in the world.
The results of the 2004 Durex global sex survey concluded that South Africans were amongst those most likely to have unsafe sex without checking their partner's sexual history.
"According to the survey, 58 percent of South Africans have had unprotected sex without knowing their partner's sexual history, which means that South Africans are taking serious risks," said a statement released by Durex South Africa.
The figure is much higher than the worldwide average of 35 percent of people who admitted to having had unprotected sex.
But South Africans did express serious concern about AIDS, with 77 percent saying it is the most important sexual health issue today.
The country grapples with a sky-high AIDS rate with UNAIDS estimating that 5.3 million people, or one in every nine, are HIV-infected.
"Forty-nine percent of South Africans believe the government should be investing more heavily in sex education programmes in schools as the best way to help prevent HIV/AIDS and other sexually transmitted infections.
"Perhaps this is because 21 percent of South Africans have never received any formal sex education," the statement said.
More than 350,000 people from 41 countries participated in the survey.
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Tue Oct 12, 8:46 AM ET
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ADDIS ABABA (AFP) - Africa's farmers and rural communities have become the forgotten victims of HIV/AIDS, health experts and political leaders from the across the continent were told at a conference in Addis Ababa.
Rural communities are being torn apart while the bulk of AIDS prevention and support work focusses on the continent's cities, according to speakers at the UN's Commission on HIV/AIDS and Governance in Africa (CHGA).
Development workers, researchers and politicians, including Kenneth Kaunda, the former president of Zambia, were in the Ethiopian capital for the commission's third session of open discussions and debates.
The discussions will feed into CHGA's final report on the long-term impact of the pandemic in Africa, which is due to be submitted to the UN Secretary General Kofi Annan in June 2005.
"Earlier in the pandemic, HIV/AIDS was viewed merely as an urban phenomenon, and most of the response is still focussed there," said K.Y. Amoako, Executive Secretary of the UN's Economic Commission for Africa, as he opened the session.
"Now, however, we can see that the epidemic has spread to our rural areas where the vast majority of Africans live," he added.
"Households are losing key productive members in their prime and communities are losing the main producers of food. Crucial knowledge is lost and the fabric of rural communities is being torn apart," he said.
The Commission includes prominent international figures among its members, including Joy Phumaphi, the World Health Organisation's assistant Director General, Peter Piot, head of UNAIDS, and Richard Feachem, head of the Global Fund for AIDS, Tuberculosis and Malaria.
Africa accounts for 25 million out of the estimated 38 million people across the world infected with HIV. The vast majority of infected Africans are women, according to UNAIDS estimates.
The conference was also addressed by Ethiopian President Girma W. Giogis, who told delegates that Africa's families were taking the brunt of the epidemic.
"Our cemeteries are filled beyond capacity. Parents are dying from HIV/AIDS or burying their children; a generation of fathers and mothers is being lost leaving the grandparents to grieve and raise the next generation," he said.
"The resulting social decay and community breakdown is threatening the socio-economic fabric of our continent, particularly in southern and eastern Africa," he added.
Joseph Tumushabe, of Uganda's Makerere University, told the conference that 70 percent of the world's HIV/AIDS sufferers were from Africa, and that two-thirds of the populations of the continent's 25 most affected countries were based in rural areas.
"We are now coming to the point where we are going to get information and statistics and data with regard to what is happening to the population, particularly in rural areas. If we are going to going to confront HIV/AIDS, we have got to look at rural areas and communities," he said.
The problems of AIDS are exacerbated outside cities, he added, because such communities are more vulnerable to a range of social and economic ills, including famine, floods and conflict.
As key workers and family members succumb to AIDS, more children are taken out of school, oral knowledge and traditional farming practices die out and the range of crops grown contracts, he explained.
Later this year, the commission will meet in Ghana to discuss the impact of AIDS on the world of work and again in Cameroon to discuss gender and AIDS orphans.