Booster Shots

Oddities, musings and news from the health world

Category: AIDS

Female empowerment can help fight HIV, researchers say

June 16, 2010 | 11:42 am

A team of American and South African researchers has an unconventional prescription for reducing the risk of HIV among women – female empowerment.

Hiv If young women in rural South Africa enjoyed true gender equality with their male partners, nearly 14% of the new HIV infections recorded between 2002 and 2006 could have been avoided, the researchers said. In addition, if – by some miracle – all instances of physical or sexual violence by men could have been prevented, so would 12% of the new HIV cases diagnosed during that four-year period.

Those calculations come from a study published online Wednesday in the journal Lancet. The researchers crunched data from a trial designed to test the effectiveness of an HIV-prevention program called Stepping Stones.

Of the 1,099 women included in the Lancet study, 128 acquired HIV during the course of the trial. That worked out to an overall incidence rate of 6.2 new infections per 100 person-years. But the rates weren’t uniform across all groups of women.

Among those with “low relationship power equity,” there were 8.5 new cases per 100 person-years; for women in more equal relationships, there were only 5.5 new infections per 100 person-years. The researchers also found that among women who were victims of intimate partner violence more than once during the study, the infection rate was 9.6 new cases per 100 person-years; for all other women, there were 5.2 new cases per 100 person-years.

Cultures that “celebrate male strength and toughness” tend to tolerate a higher degree of male control over women, and that makes women more vulnerable to the adverse consequences of “risky sexual behavior, predatory sexual practices, and other acts of violence against women,” the researchers wrote. Therefore, health officials should be concerned not only with the availability of HIV medications but with social programs “that address violence and gender inequity in relationships.”

It may sound pie-in-the-sky, but the Office of the U.S. Global AIDS Coordinator has already earmarked $30 million for pilot programs aimed at preventing gender-based violence in Tanzania, Mozambique and the Democratic Republic of Congo, according to Jay Silverman, director of violence-prevention programs at the Harvard School of Public Health. In an editorial that accompanies the study, Silverman wrote:  “We must hope that this initial allocation will be followed by far greater investment.”

-- Karen Kaplan

Photo: New research indicates that women like Claudia Pena (above) would be less vulnerable to HIV infection if they were on more equal footing with their partners. She got HIV from her live-in boyfriend, who was sleeping with other men. Credit: Genaro Molina / Los Angeles Times

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Catching up with riders on the AIDS/LifeCycle ride from S.F. to L.A.

June 10, 2010 |  2:59 pm

The AIDS/LifeCycle ride kicked off Sunday, as about 2,150 people started pedaling their bicycles for the seven-day, 545-mile ride from San Francisco to Los Angeles to raise money for people with HIV.

LifeCycle The official AIDS/LifeCycle site allows us armchair cyclists to experience the event, courtesy of copious photos and daily postings from several bloggers. From roadie Ken, (a roadie in this context is part of the support crew -- people who serve food, help with medical needs, provide water, load gear, etc.), we get this: "Roadie Revelation #2 -- When a rider approaches you with a sad look in their eyes and says, 'I just want to apologize in advance,' it means their bag is heavy. Like really heavy."

But the riders are pressing on in good spirits. On day four, the second-longest day of the ride (97.7 miles), blogger Jasmine posted this: "Even amidst the breathtaking land and seascapes today and the entertainment at reststops, there was a moment when I was reminded again that our participation is so much more than just riding bikes. At mile 34, on a rural road paralleling the highway, a woman sat outside her minivan, waving at passing cyclists and saying, 'thank you for riding for me.'"

The L.A. Times' Michael Owen is also taking part in the ride, and so far has posted updates from day one and day four on the Outposts blog. On Wednesday, he posted this: "But for all its danger, the bike is also an affirmation of freedom, of strength, even of recovery. Over and over this week I've heard stories of coming to this ride that combine a loss -- often the AIDS-caused death of someone loved--with a decision to reverse one's own physical decline, however mild (or potentially severe -- the Positive Pedalers, a group of HIV-positive cyclists, have a highly visible presence on the ride). For many people, the ride is no mere demonstration of commitment to 'fighting AIDS.' It’s a lever, flipping the sentiments that accompany loss and failure into a tangible dividend for the suffering. Just as the bicycle lends a new scale to our physical movement, the ride multiplies our hope."

For those who would like to greet the riders when they arrive in Los Angeles, closing ceremonies take place June 12 at the VA Center on Wilshire Boulevard.

-- Jeannine Stein

Photo: Riders from a previous AIDS/LifeCycle pedal through California. Credit: AIDS/LifeCycle


The 7-day, 545-mile AIDS/LifeCycle ride: more summer camp, less Tour de France

June 1, 2010 |  5:32 pm

Millions of people have made the trek from San Francisco to Los Angeles, but far fewer have done it on a bicycle. On Sunday, 2,150 cyclists will brave the 545-mile trip as part of the seven-day AIDS/LifeCycle ride to raise money to care for people with HIV.

LifeCycleThis is the ride's ninth year, and the fundraiser, co-produced by the L.A. Gay & Lesbian Center and the San Francisco AIDS Foundation, is part athletic feat, part camping trip, part social gathering and part celebration. This year the trip goes through 57 towns and jurisdictions, plus eight counties. It features riders from age 18 to 80 who are from 41 states and Washington, D.C., and eight countries. They will consume 420 gallons of coffee (is that all?), 44,600 eggs, 6,000 Clif bars, and 5,400 Pop-Tarts. Yes, Pop-Tarts.

To get the scoop on what first-time riders should expect, we spoke with David Rae, who is participating in his third ride. The financial planner from West Hollywood heads up the 30-person Team Popular (it's not an ego thing, they named themselves after the song from "Wicked"), which has so far raised about $150,000.

The first time Rae rode in the event, it was to challenge himself athletically. Although he didn't even own a bike, he bought one and started training. His training for this year included shorter rides during the week and a longer ride on the weekends out to Malibu, Ventura or Palos Verdes. He also organized a team training overnight ride to Santa Barbara: "This gives people a sampling of the real ride, with rest stops, and you get to meet new people."

Doing copious amounts of cardio is the best preparation, says Rae; that includes group cycling classes, the elliptical trainer and anything else that gets the heart rate up for an extended period. But doing the actual ride, he discovered, isn't about getting all Lance Armstrong and beating everyone else, it's about raising money, doing something healthful and experiencing the camaraderie that comes from participating in such a sizable event.

"There's so much support," he said. "There are cheerleaders who are out there with megaphones cheering you on, and people will even give you a push if you need it. It's not a race by any stretch of the imagination. If you get a flat tire, people will stop and help you. Doing the ride is actually easier than the training, since there are organized pit stops and food every 20 miles. You get more breaks than you do while you're training. The energy is always there -- it's like summer camp."

-Jeannine Stein

The AIDS/LifeCycle ride starts in San Francisco and ends in Los Angeles. Photo from last year's event courtesy of AIDS/LifeCycle


Experts debate lifting blood donation ban on gay men in stable relationships

May 27, 2010 |  9:53 am

Men who have sex with men are not permitted to donate blood in the United States, Canada and many other countries. This ban was designed to stop the spread of HIV through blood transfusions and was implemented with broad support in 1983.

Blood But times have changed, and the rule no longer makes sense, say experts in HIV research writing in the current issue of the Canadian Medical Assn. Journal. The ban on donations from gay men was necessary early in the HIV epidemic when there was no way to screen for HIV antibodies in blood and the disease was appearing largely in that group.

But rigorous screening tests now exist, and rules permit people in stable, monogamous relationships to donate blood even though HIV infection now occurs in a broad swath of people, both homosexual and heterosexual. "...donors who have had heterosexual unprotected sex with multiple partners are not necessarily prevented from donating, provided the heterosexual donor claims to be aware of the sexual background of each of his or her sexual partners," the authors wrote.

Similarly, gay men in stable, long-term monogamous relationships should be allowed to donate blood after a deferral period -- a waiting period -- of one year, the editorial states. Allowing this group to donate would increase the blood supply while not significantly endangering it. They estimate that allowing gay men to donate after a one-year deferral period would result in a risk of HIV in one unit of blood for every 11 million units collected.

The ban on donations from gay men is a matter of growing controversy. Both the HIV Medical Assn. in the United States, the American Red Cross and the American Assn. of Blood Banks has expressed support for a change in rules to allow donation after a deferral period.

"The current policy is counterproductive in terms of loss of donors, loss of good will, student protests, donor boycotts and lawsuits, among other negative effects," the authors wrote.

-- Shari Roan

Photo credit: Julie Markes  /  For The Times


Lubricants may increase disease risk of anal sex, studies show

May 25, 2010 |  5:00 pm

The use of lubricants may make anal sex more comfortable, but they may also increase the risk of spreading sexually transmitted infections, including HIV, researchers said Tuesday. Many experts have been concerned about the potential effects of such lubricants, but there have previously been virtually no studies about how they affect disease.

In the United States, as many as 90% of gay men practice anal sex, according to International Rectal Microbicides Advocates, a group that has been lobbying for the development of microbicides — chemical agents that can kill HIV during sexual acts. Estimates in the U.S. also suggest that as many as 35% of women have participated in anal sex at least once. The majority of both sexes are thought to use lubricants to ease penetration.

Epidemiologist Pamina H. Gorbach of UCLA's Geffen School of Medicine and her colleagues studied 879 men and women between October 2006 and December 2008. The participants were tested for gonorrhea and chlamydia and queried about their sexual behavior in private, computer-based interviews, which have been shown to elicit more truthful answers than face-to-face interviews. Of the 879 participants, 229 men and 192 women reported having receptive anal intercourse in the past year, and about half said they used lubricants. When the team analyzed the data, Gorbach told a Pittsburgh microbicides meeting, they found that those who used lubricants were three times as likely to have contracted a rectal infection.

A partial explanation for the increased risk may have been provided by Charlene Dezzutti, a reproductive science specialist at the University of Pittsburgh, and her colleagues. They studied the effects of six of the most popular lubricants on rectal cells and tissues in laboratory dishes.They found that many of the products had high concentrations of dissolved salts and sugars that draw water out of cells, weakening and even killing the cells. Some of them even stripped away significant portions of the surface epithelial cells on the rectal tissue, the layer of cells that serves as a protective barrier. They also studied the effect of the lubricants on beneficial bacteria in the rectum.

Two of the six lubricants, PRE and Wet Platinum, were shown to be safest for the cells, while Astroglide was the most toxic to cells and tissue. KY Jelly had the worst effect on rectal bacteria, essentially wiping out the entire colony. ID Glide and Elbow Grease had intermediate effects, the team found. None of the lubricants was found to have measurable anti-HIV activity.

The team now plans to investigate the effect of the lubricants on HIV infections.

-- Thomas H. Maugh II


Eradication of smallpox may have set the stage for HIV pandemic, study says

May 18, 2010 | 11:51 am

The worldwide eradication of smallpox in the mid-20th century was a remarkable public health achievement, but it may have set the stage for the HIV pandemic of the latter half of the century, researchers reported Tuesday.

Laboratory tests suggest that immunity to smallpox triggered by the vaccinia (smallpox) vaccine can inhibit the replication of the AIDS virus. Such vaccination could have kept HIV transmission partially under control in the early days of the outbreak, but withdrawal of the smallpox vaccine in the 1950s would have freed it to spread unfettered, the researchers said.

The most common form of HIV is thought to have evolved from a simian immunodeficiency virus found in chimpanzees of southern and western Africa sometime around 1931. It spread slowly until the mid- to late-1950s, when it began to spread exponentially. Wars, misuse of medical equipment and contamination of a polio vaccine have been suggested as possible causes of the spread, but such theories have either been disproved or do not sufficiently explain the behavior of the HIV pandemic, said Dr. Raymond S. Weinstein of the biodefense program at George Mason University in Manassas, Va.

Weinstein and his colleagues noted that the progression of an HIV infection can be mitigated by a co-infection with certain other viruses, such as human herpesvirus 6 or 7 or the paramyxovirus that causes measles. Such viruses interfere with a cellular receptor of white cells that is also used by HIV. The vaccinia virus also blocks this receptor.

To test their idea, Weinstein and his colleagues recruited 20 Navy personnel. Half had received normal vaccinations and half had received both those vaccinations and, within the previous three to six months, vaccination against smallpox. The researchers extracted white blood cells from all the subjects and exposed them to HIV in a culture dish. They reported in the journal BMC Immunology that HIV replication was slowed by about 80% in the cells from those who had received smallpox vaccination.

"While these results are very interesting and hopefully may lead to a new weapon against the HIV pandemic, they are very preliminary and it is far too soon to recommend the general use of vaccinia immunization for fighting HIV," Weinstein said in a statement. Given the great difficulties researchers have encountered in trying to develop an HIV vaccine, the ironic fact is that we may once have had a vaccine that is more effective against the virus than anything that has since been developed, and we threw it away.

-- Thomas H. Maugh II


New FDA warning on HIV drugs Invirase and Norvir

February 23, 2010 |  9:13 am

The Food and Drug Administration said Tuesday it is investigating reports of adverse reactions from a combination of two HIV drugs and cautioned physicians and patients to be on the alert for such events. Both drugs, Invirase (saquinavir) and Norvir (ritonavir), are in the family of HIV medications known as protease inhibitors. They are sometimes used together in cocktails to reduce levels of the AIDS virus.

The FDA says it has received reports that combinations of the two drugs can alter heart rhythms by prolonging what are known as QT and PR intervals on an electrocardiogram. Prolongation of the QT interval can lead to an abnormal rhythm known as torsades de pointes, while prolongation of the PR interval can lead to a different abnormal rhythm called heart block. In either condition, the patient may experience lightheadedness, fainting or abnormal heart beats. Torsades de pointes can progress to a potentially lethal condition called atrial fibrillation, in which the heart beats so erratically that it can no longer pump blood effectively.

The agency is still investigating the reports and is not yet making recommendations about the drugs. Patients experiencing problems with the drugs should report them to the FDA here.

Invirase is marketed by Genentech of San Francisco, while Norvir is marketed by Abbott Laboratories of Abbott Park, Ill.

-- Thomas H. Maugh II


Old HIV drug found to produce rare liver problem, FDA says

February 1, 2010 | 11:13 am

Didanosine, the second drug approved for the treatment of HIV infections and one of the oldest weapons in the AIDS armamentarium, has been found to produce rare cases of potentially fatal liver disease in patients taking it for long periods, the Food and Drug Administration announced Monday. Didanosine, marketed by Bristol-Myers Squibb under the brand names Videx and Videx EC (an extended release version), was approved by the FDA in 1991, joining AZT as the only drugs then approved to treat HIV.  It is a reverse transcriptase inhibitor, blocking the action of the key enzyme used by HIV in replicating. It has limited value when used alone because the virus rapidly mutates to overcome it, and is thus generally used in drug cocktails.

In the 18 years since the drug has been on the market, the FDA has received 42 reports of a rare disorder called non-cirrhotic portal hypertension. It results when high blood pressure occurs in the portal vein--a major vein of the liver--causing the vein to enlarge and weaken. Once the vein wall is weakened, it can split open, leading to fatal bleeding. Non-cirrhotic means that the condition is not caused by cirrhosis of the liver, a consequence of alcohol abuse.

Of the 42 cases, 26 were males, 14 were females and no gender was reported for two. Their ages ranged from 10 to 66 years. All had been taking the drug for months or years before the condition developed. Four of the patients died from bleeding or organ failure. Eight patients were treated by surgical techniques to reinforce the vein or by a liver transplant. Only the three patients who had transplants fully recovered.

The FDA concluded that the benefits of the drug outweigh the risk, but is increasing the package warning to alert physicians and patients to the possibility that the problem will develop. The drug already has a box warning of an increased risk of lactic acidosis and hepatomegaly with steatosis, caused by damage to mitochondria in liver cells.

-- Thomas H. Maugh II


Rodent of the Week: Preventing HIV infection

January 22, 2010 |  1:00 pm

Rodent_of_the_week A study in mice raises the possibility of preventing HIV transmission in humans. Researchers at the University of North Carolina, Chapel Hill, found that administering antiretroviral drugs to mice prior to HIV exposure protected against intravenous and rectal transmission of the virus. The study was published online this week in PLoS One.
 
The mice used in the study were humanized, meaning they were transplanted with human bone marrow, liver and thymus cells, which results in a functioning human immune system. In the study, the mice either received no drugs or were given commonly prescribed antiretroviral drug therapy and then were exposed to HIV either rectally or intravenously at a higher level than would occur in a typical human.

None of nine treated mice exposed rectally showed signs of HIV infection. But 12 of the 19 control mice became infected. Among the mice exposed intravenously, all six of the control mice became infected but seven of the eight treated mice were protected against infection.
 
"These results provide evidence that a universal approach to prevent all forms of HIV transmission in all settings might be possible," J. Victor Garcia-Martinez, the lead author of the study, said in a news release. "This could greatly facilitate the implementation of a single program capable of targeting virtually all groups of people at high risk of HIV infection."
 
Results in mice cannot be extrapolated to humans, the researchers noted. However, there are some pre-exposure trials underway in humans, and this new paper should bolster support for moving forward with that research.
 
-- Shari Roan
 
Photo credit: Advanced Cell Technology Inc.
 


Microbicide gel against HIV fails major trial, disappointing researchers

December 15, 2009 | 10:53 am

A microbicide gel designed to block the transmission of the AIDS virus to women has failed the largest clinical trial to date, a bitterly disappointing finding for researchers that likely spells the end of research on this form of such products. The findings announced Monday by England's Medical Research Council represent a major letdown because results from a smaller study presented in February at a major AIDS conference suggested that the microbicide could block transmission of HIV by 30%, although the results were not statistically significant. Researchers are now turning their attention to microbicides containing anti-HIV drugs.

Short of a vaccine, vaginal microbicides are considered one of the most promising ways to prevent transmission of the virus to women. Such an approach would give women a great deal of control over their health when marital or other sexual partners refuse to use condoms. The idea is that the microbicide will tie up or kill the virus in the vagina before it can penetrate the tissues and infect the woman. Such a product must not be unpleasantly messy or sticky and should be able to block the virus without impeding the much larger sperm.

The trial involved a microbicide called PRO 2000 manufactured by Endo Pharmaceuticals of Chadds Ford, Penn. Its active ingredient is a polymer of naphthalene sulfonate designed to bind to receptors on the surface of HIV, preventing it from penetrating vaginal tissue. Tests in the laboratory showed that it binds strongly to the virus, suggesting that it would be effective in actual use.

The trial, sponsored by the London-based Microbicides Development Programme--a coalition of 16 European and African research institutions--involved 9,385 African women in four countries. The women were given either a placebo gel, a gel containing 0.5% of PRO 2000 or a gel containing 2% PRO 2000. The gels were to be used before and after sex. The women were also counseled to use condoms whenever possible and on other ways to minimize the risk of infection.  The women reported that they liked the gel and many were disappointed when they had to stop using it.

The arm of the trial using the higher concentration was halted in February 2008 when it became clear that the microbicide would not work at that concentration.

There were 130 HIV infections in the 3,156 women who received the 0.5% gel and 123 in the 3,112 women receiving the placebo gel during the 12 to 24 months of follow-up. That works out to a rate of 4.5 infections per 100 women-years in the group receiving PRO 2000 and 4.3 in the placebo group.

"This result is disheartening, particularly in light of the results of a smaller trial sponsored by the U.S. National Institutes of Health," the study's chief investigator, Dr. Sheena McCormack of the Medical Research Council, said in a statement. "Nevertheless, we know that this is an important result and it clearly shows the need to undertake trials which are large enough to provide definitive evidence for whether a product works."

-- Thomas H. Maugh II



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