ICAAC: Women who shed HSV in genitals shed more HIV

Genital shedding of herpes simplex virus-2 (HSV-2) is associated with increased genital shedding of HIV, according to a study presented to the 45^th Interscience Conference on Antimicrobial Agents and Chemotherapy in Washington DC. The study investigators suggest that providing the anti-HSV drug aciclovir to women with genital ulcerative disease may be a way of reducing the risk of HIV transmission.

It is known that the ulcers and subclinical disease caused by HSV-2 can increase an individual's risk of being infected with HIV. It is less clear, however, if infection with HSV-2 increases the risk of an HIV-positive individual transmitting HIV infection.

Investigators from Ghana, the Central African Republic, France and the UK conducted a randomised controlled trial to see if the use of aciclovir to treat genital ulcerative disease had an impact on the genital shedding of HIV.

A total of 274 women with genital ulcerative disease in Ghana and the Central African Republic were recruited to the trial. Blood samples and cervico-vaginal lavage were examined for the presence of HSV-1 and HSV-2, HIV viral load and HSV-2 genetic material.

Of the 163 women who were included in the study, 45% were infected with HIV and 76% with HSV-2. The investigators noted that women who tested positive for HSV-2 were significantly more likely to be infected with HIV (56%) than women who were HSV-2-negative (5%, p < 0.001).

In addition, the investigators noted that among the HSV-2-positive women, those infected with HIV were over twice as likely to shed HSV-2 than HIV-negative women (70% versus 29%, p < 0.001).

The investigators then restricted their analysis to the 53 women who were infected with both HIV and HSV-2. They observed that 76% of women who were shedding HSV-2 in their genitals were also shedding HIV. However, only 44% of women who were not shedding HSV-2 in their genitals had detectable HIV in this compartment. The difference was statistically significant (p = 0.02).

In further analysis, the investigators examined the 28 women who were shedding both viruses. They found that there was a correlation between the amounts of HIV and HSV-2 detected in the genital tract (p = 0.04). However, there was no difference in the HIV plasma viral loads between women who were shedding HSV-2 in their genitals and those who were not.

The investigators conclude, “these findings suggest that HSV-2 replication is associated with increased genital infectivity and support the hypothesis of aciclovir use in women with genital herpetic lesions as an effective strategy to reduce the infectivity of HIV."