June 27, 2012

Condition Makes Women More Susceptible to HIV?

(Ivanhoe Newswire) — A new investigation led by UCSF has found that the risk of female-to-male HIV transmission is increased 3-fold for women with bacterial vaginosis.

Bacterial vaginosis is a condition where the normal balance of microorganisms naturally found in the vagina is altered. The disruption of vaginal flora takes place when the amount of helpful bacteria is reduced and the harmful bacteria is increased.

"Previous research has shown that bacterial vaginosis can increase a women's risk of becoming infected with HIV as much as sixty percent. Our study is the first to show that the risk of transmitting HIV is also elevated. Our findings point to the need for additional research to improve the diagnosis and treatment of bacterial vaginosis, which is extremely common in sub-Saharan Africa, the region of the globe with the highest burden of HIV," the study's lead author, Craig R. Cohen, MD, MPH, professor of obstetrics, gynecology and reproductive sciences at UCSF, was quoted as saying.

The researchers assessed the association between bacterial vaginosis and female-to-male HIV transmission risk in a prospective study involving 2,236 HIV positive women and their uninfected male partners from seven African countries. It was found that bacterial vaginosis was associated with significantly increased risk for female-to-male HIV transmission after controlling for socio-demographic factors, sexual behavior, male circumcision, sexually transmitted infections, pregnancy, and levels of HIV in the blood of HIV-infected women.

In addition to increasing the risk of becoming infected with HIV, bacterial vaginosis can increase the risk of getting other sexually transmitted infections and increase the risk of preterm delivery. HIV-infected women with bacterial vaginosis may also have higher levels and greater shedding of the virus from the cervix and vagina.
"We looked at the increased shedding of HIV in the genital tract, but that was not sufficient to explain the increased risk of female-to-male HIV transmission. It is also possible that bacterial vaginosis causes inflammation and that could be a factor. We don't really understand the relationship between vaginal flora and inflammation," Cohen was quoted as saying.

Additionally, Cohen was quoted as saying, "we think it's likely that the sharing of genital tract microbiota between women and men may be implicated as a cause of the transmission risk. The interrelationship of the sharing of flora remains poorly understood and is an important avenue for future research."

Besides providing a better understanding of vaginal flora, developing more therapeutics for bacterial vaginosis, such as better drugs and probiotics, would significantly boost women´s health as well as decrease HIV acquisition and transmission risks.

Source: PLoS Medicine, June 2012