Breakthrough AIDS : Helps prevent infection by Gel

AIDS (Acquired Immune Deficiency Syndrome)

Breakthrough AIDS : Helps prevent infection by Gel

For the first time, a vaginal gel has proved capable of blocking the AIDS virus : It cut in half a woman's chances of getting HIV from an infected partner in a study in South Africa. Scientists called it a breakthrough in the long quest for a tool to help women whose partners won't use condoms. The results need to be confirmed in another study, and that level of protection is probably not enough to win approval of the microbicide gel in countries like the United States, researchers say. But they are optimistic it can be improved. "We are giving hope to women," who account for most new HIV infections, said Michel Sidibe in a statement. He is executive director of the World Health Organization's UNAIDS program. A gel could "help us break the trajectory of the AIDS epidemic," he said. And Dr. Anthony Fauci of the U. S. National Institutes of Health said, "It's the first time we've ever seen any microbicide give a positive result" that scientists agree is true evidence of protection. The gel, spiked with the AIDS drug tenofovir, cut the risk of HIV infection by 50 percent after one year of use and 39 percent after 2 1/2 years, compared to a gel that contained no medicine.To be licensed in the U. S., a gel or cream to prevent HIV infection may need to be at least 80 percent effective, Fauci said. That might be achieved by adding more tenofovir or getting women to use it more consistently. In the study, women used the gel only 60 percent of the time; those who used it more often had higher rates of protection. The gel also cut in half the chances of getting HSV-2, the virus that causes genital herpes. That's important because other sexually spread diseases raise the risk of catching HIV. Even partial protection is a huge victory that could be a boon not just in poor countries but for couples anywhere when one partner has HIV and the other does not, said Dr. Salim Abdool Karim, the South African researcher who led the study. In the U. S., nearly a third of new infections each year are among heterosexuals, he noted. Countries may come to different decisions about whether a gel that offers this amount of protection should be licensed. In South Africa, where one in three girls is infected with HIV by age 20, this gel could prevent 1.3 million infections and 826,000 deaths over the next two decades, he calculated. He will present results of the study Tuesday at the International AIDS Conference in Vienna. The research was published online Monday by the journal Science. "We now have a product that potentially can alter the epidemic trends ... and save millions of lives," said Dr. Quarraisha Abdool Karim, the lead researcher's wife and associate director of the South African program that led the testing. It's the second big advance in less than a year on the prevention front. Last fall, scientists reported that an experimental vaccine cut the risk of HIV infection by about 30 percent. Research is under way to try to improve it.If further study shows the gel to be safe and effective, WHO will work to speed access to it, said its director-general, Dr. Margaret Chan. The gel is in limited supply; it's not a commercial product, and was made for this and another ongoing study from drug donated by California-based Gilead Sciences Inc., which sells tenofovir in pill form as Viread. If further study proves the gel effective, a full-scale production system would need to be geared up to make it. The study tested the gel in 889 heterosexual women in and near Durban, South Africa. Researchers had no information on the women's partners, but the women were heterosexual and, in general, not in a high-risk group, such as prostitutes.Half of the women were given the microbicide and the others, a dummy gel. Women were told to use it 12 hours before sex and as soon as possible within 12 hours afterward. At the study's end, there were 38 HIV infections among the microbicide group versus 60 in the others.The gel seemed safe — only mild diarrhea was slightly more common among those using it. Surveys showed that the vast majority of women found it easy to use and said their partners didn't mind it. And 99 percent of the women said they would use the gel if they knew for sure that it prevented HIV. This shows that new studies testing the gel's effectiveness without a placebo group should immediately be launched, said Salim Abdool Karim. The only other study testing the gel now compares it to placebo and will take a couple more years to complete. The study was sponsored by the Centre for the AIDS Programme of Research in South Africa, or CAPRISA; Family Health International; CONRAD, an AIDS research effort based at Eastern Virginia Medical School; and the U. S. Agency for International Development, or USAID. Gilead has licensed the rights to produce the gel, royalty-free, to CONRAD and the International Partnership on Microbicides for the 95 poorest countries in the world, said Dr. Howard Jaffe, president of the Gilead Foundation, the company's philanthropic arm. The biggest cost of the gel is the plastic applicator — about 32 cents, which hopefully would be lower when mass-produced, researchers said. Mitchell Warren, head of the AIDS Vaccine Advocacy Coalition, a nonprofit group that works on HIV prevention tools, said the study shows a preventive gel is possible."We can now say with great certainty that the concept has been proved. And that in itself is a day for celebration," he said.

IDS (Acquired Immune Deficiency Syndrome)

IDS (Acquired Immune Deficiency Syndrome) is the final and most serious stage of HIV disease, which causes severe damage to the immune system. AIDS is the fifth leading cause of death among persons between ages 25 and 44 in the United States. About 47 million people worldwide have been infected with HIV since the start of the epidemic. The Human Immunodeficiency Virus (HIV) causes AIDS. The virus attacks the immune system and leaves the body vulnerable to a variety of life-threatening illnesses and cancers.Common bacteria, parasites, and viruses that ordinarily do not cause serious disease in people with fully functional immune systems can cause fatal illnesses in people with AIDS. HIV has been found in tears, nervous system tissue, blood, semen, vaginal fluid, and breast milk. However, only blood, semen, vaginal secretions, and breast milk have been proven to transmit infection to others.

Transmission of the virus occurs :

1. through sexual contact -- including oral, vaginal, and anal sex

2. through blood -- via blood transfusions or needle sharing

3. from mother to child -- a pregnant woman can passively transmit the virus to her fetus, or a nursing mother can transmit it to her baby


Other transmission methods are rare and include accidental needle injury, artificial insemination with donated semen, and through a donated organ.HIV infection is not spread by casual contact (such as hugging and touching), by touching dishes, doorknobs, or toilet seats previously touched by a person infected with the virus, during participation in sports, or by mosquitoes.It is not transmitted to a person who DONTATES blood or organs, because hospitals do not re-use syringes and sterilize all devices involved in such procedures. However, HIV can be transmitted to the person RECEIVING blood or organs from an infected donor.Those at highest risk include homosexual or bisexual men engaging in unprotected sex, intravenous drug users who share needles, the sexual partners of those who participate in high-risk activities, infants born to mothers with HIV, and people who received blood transfusions or clotting products between 1977 and 1985 .AIDS begins with HIV infection. People infected with HIV may have no symptoms for ten years or longer, but they can still transmit the infection to others during this symptom-free period. Meanwhile, their immune system gradually weakens until they develop AIDS.Acute HIV infection progresses over time to asymptomatic HIV infection and then to early symptomatic HIV infection. Later, it progresses to AIDS. Most individuals infected with HIV will progress to AIDS, if not treated. However, there is a tiny group of patients who develop AIDS very slowly or never at all. These patients are called non-progressors and many seem to have a genetic difference which prevents the virus from attaching to certain immune receptors.

Symptoms : The symptoms of AIDS are primarily the result of infections that do not normally develop in individuals with healthy immune systems.Patients with AIDS have had their immune system depleted by HIV and are very susceptible to such opportunistic infections. Common symptoms are fevers, sweats, swollen glands, chills, weakness, and weight loss. Initial infection may produce no symptoms. Some people with HIV infection remain without symptoms for years between the time of exposure and development of AIDS. However, some people develop what feels like a "flu" about two weeks after contracting the virus.

Treatment : There is no cure for AIDS at this time. However, several treatments are available that can delay the progression of disease for many years and improve the quality of life of those who have developed symptoms. Antiviral therapy suppresses the replication of the HIV virus in the body. A combination of several antiretroviral agents, termed Highly Active Anti-Retroviral Therapy (HAART), has been highly effective in reducing the number of HIV particles in the blood stream (as measured by a blood test called the viral load). This can help the immune system bounce back for a while and improve T-cell counts.