HIV Prevention
The Effect of Contraceptives on HIV Transmission
8 years ago
Ongoing debates over injectable contraceptives for HIV prevention, and the idea that there is an increased risk of contracting HIV when using such, have been escalating. Researchers have found their studies inconclusive – some reports show that risk increases and some claim that it does not. So why the discrepancies, and what is the biological reason for such findings?
To start, the contraceptive being accused of aiding the transmission of HIV is known as Depo-Provera or DMPA. Reports that it increases the risk for HIV infection are growing, yet studies come up with data that is contradictory. To determine the real risk, along with an explanation, a thorough investigation was made. Over 800 women were analyzed. All started out HIV free and were enrolled in family planning clinics. The women were divided into three groups. One group used oral contraceptives, the other DMPA, and the final group did not use hormonal contraceptives. Later, 200 of the participants became infected with HIV. A look at the vaginal flora of the women within each group gave researchers the explanation they had been searching for.
For each group, there were those with a healthy vaginal environment and those with infections from either parasites, bacteria, or fungi. Further, it was confirmed that those taking the DMPA contraceptive presented with more changes to the immune system, which meant more vaginal infections, increased inflammation, and an increased risk of contracting HIV. The compromised vaginal state proved a poor resistor to infection, including contracting HIV. Certain protein levels are known to attract and aid HIV in spreading. However, the results of this study also showed that certain oral contraceptives could alter the immune system or suppress it. This too can lead to environmental changes within the vagina that can lead to easier transmission of HIV.
It is the hope of those researchers that the information from this study will move institutions to educate their patients and their partners. That way individuals can make informed choices about the types of contraceptives they decide to use, especially for HIV prevention. Thus, spread of HIV can be slowed and hopefully, in many cases, prevented.
Cocaine’s Effect on the Immune System and HIV Infection
8 years ago
Research out of UCLA links cocaine use to a weakened resistance to HIV. What was involved in the study? And what does it mean by at-risk individuals? Read on to learn how cocaine use increases your chances of HIV infection.
It is well documented that there are surprising similarities between the immune systems of mice and humans. That makes them the perfect test subject when it comes to studying infection and deadly diseases. Therefore, a study that had previously only been performed in a dish has now been tested with live subjects. What was the result? Let’s consider the process first.
In previous lab tests, it was determined that the use of cocaine over a period of just three days is enough to affect the immune system. The body starts out with cells that can put up quite a fight with HIV. These immune cells are called CD4 T cells. The cocaine exposure, however, blocks the normal working of these cells by stimulating two of the cell’s receptors.
For five days, mice were given injections. Half were given cocaine, and the other half was given a placebo with saline. Next, HIV was introduced via injections, and then the cocaine/placebo routine continued for another 14 days. At the end of the study, they not only discovered that the mice who were given cocaine had higher concentrations of the virus in their system but also that nearly half of the mice given a placebo had undetectable amounts of the disease.
The CD4 T cells, however, were not affected as suspected. On the contrary, it was the CD8 T cells that seemed to cease functioning. Either way, though, the fact remains that cocaine made it tougher for the immune system to defend itself against HIV.
This study continues to highlight the connection between illicit drug use and HIV infection. It reveals that anyone who uses cocaine is placing themselves at higher risk for infection. While ceasing drug use is the best option, frequent testing is important for one who pursues an at-risk lifestyle.
Research Shows Why HIV Progresses Faster in Some
8 years ago
A study was performed to determine why HIV is able to evade the efforts of current HIV treatments and persist in the body. This study will lead to improved HIV prevention. Let’s look at a breakdown of the HIV genetic code and what researchers found which may eventually lead to better treatments.
Researchers understand the way HIV spreads within the body. In order for HIV to enter a host cell, there is a sort of viral envelope. This envelope contains two glycoprotein molecules that have been named gp41 and gp120. The gp120 molecule has been further studied and broken down into sections that have been labelled with either a C or a V and the numbers 1 through 5.
In turn, this genetic code tells the virus to use the R5 receptor to enter a CD4 immune cell. This entry point is the focus of most HIV drugs. However, in about half of patients the virus will avoid using the R5 entry point and switch to the X4 receptor. This change results in a worsening of the disease and difficulty treating HIV with currently available medications.
Previous research made it seem that the gp120’s V3 region was the part that was solely responsible for this change and progression in how the disease spreads within the body. While the V3 region does clearly play a role, a minute genetic change in the gp120’s C2 region also comes into play. This genetic change, though slight, could prove to be an important discovery for researchers.
Now, it is up to researchers to figure out how to put this knowledge to use in combating HIV’s ability to progress despite treatment. It is hoped that the additional knowledge as to how the disease changes which receptor it focuses on will result in finding ways to predict progression and find a way to develop better means for HIV prevention and treatment.
Risk of HIV Decreases with More Secondary Education
8 years ago
A study was performed in Botswana that revealed just one year more of secondary education produced a drastic reduction in the risk of contracting HIV. In a part of the world where approximately 1 in 4 will contract HIV over the course of a decade following school, reducing the percentage to 17 would mean thousands of fewer cases of HIV.
Also interesting to note is the fact that decreased risk of HIV infection was more significant in young women than men. It has been speculated that the reason behind these findings is that the additional year of education during this crucial stage in adolescence keeps students from participating in the same amount of risky behavior they would be taking part in if school were already over. For women especially, education seems to have a major impact, and may be a cost effective way to reduce HIV infection across Africa, where may nations currently do not provide the same educational opportunities for young girls as they do for boys.
What are the implications of this study for a nation plagued by HIV such as Botswana where a 2013 study revealed that 22 percent of individuals in the 15 to 49 age group were infected? The fact is that providing an extra year of schooling to secondary school students for free is far less of a financial burden on the nation than trying to provide treatment after infection.
The 8 percent difference in risk represents a significant improvement for both the health and the economy of the nation. HIV infection is not the only aspect of health that is improved as nations provide more education. Other concerns, such as child mortality, are also positively affected when a nation places a great emphasis on school and learning.
In short, when it comes to risk of HIV infection, education matters. Indeed, no matter where in the world you live, education plays a vital role for children to remain healthy, especially in parts of the world where education has life and death consequences.
New Understanding of Microbicide’s Effectiveness Against HIV Transmission
8 years ago
Researchers of HIV and AIDS have long known that semen has an enhancing quality on the infectiousness of HIV, as it causes the virus cells to cluster together and bind themselves to certain protein strands within the semen fluids, thus increasing their ability to attach to – and infect – host cells. This is a major reason, researchers have learned through studies, why anal sex has the highest risk potential in the transmission of HIV from one person to another. The other major reason for the high risk involved in anal sex is rupturing of anal tissue during intercourse, which causes bleeding and raises the infection potential for both partners. Recently, researchers learned that semen is further problematic in stopping the spread of HIV, as it has been shown to lessen certain antiretroviral microbicide’s effectiveness against HIV.
An antiretroviral microbicide is a new form of anti-HIV gel which is meant to be applied to the vaginal walls prior to sexual intercourse, and which was proven to effectively eliminate the HIV cells – either by killing them or causing them to be unable to bind to any host cells – but this success is only seen in the laboratory. When they started clinical trials in areas of Africa with high infection rates, they noticed that not only were the microbicides ineffective in stopping infection, sometimes they seemed to have the reverse effect, causing it to be more likely for infection to occur. They now know why this happened. The microbicide’s effectiveness against HIV was compromised by proteins within the semen which, while strengthening the HIV cell’s infectiousness, caused the microbicides to be up to twenty times less effective against stopping transmission of the virus. The researchers who conducted the study that lead to this observation are hoping to help women in the Sub-Saharan countries of Africa who, many times, have no choice about safe sex or condom use. If they can work around the negative effects of semen, which some new antiretroviral microbicides are already promising, they can help curb the spread of the disease, in these countries and around the world. As one of the authors of the study says, “This study sheds light on why these microbicides did not work, and it provides us with a way to fix this problem by creating a new compound drug combining antivirals and amyloid inhibitors.” The more they know about each step of the infection process, the more they can break these steps down and stop HIV transmission.
