Some types of vaginal bacteria may potentially interfere with vaginal gels specifically designed to prevent the risk of contracting human immunodeficiency virus (HIV).
The findings were based on a 2010 study of South African women, who utilized the vaginal gel form of the microbicide drug tenofovir, to determine the effectiveness of the drug in preventing the spread of HIV.
Previous studies have revealed that the drug was effective in preventing the transmission of HIV in high-risk males. However, those studies have not rendered positive results in women. In fact, researchers have described the findings as “disappointing”.
CAPRISA 004, a 2010 randomized trial, revealed that tenofovir gel utilized prior to sexual activity, decreased HIV incidence by 39 percent.
Scientists analyzed a subset of women with HIV throughout the duration of the study, even though they utilized the tenofovir gel on a regular basis.
The women who contracted HIV were more likely to have Gardnerella vaginalis, a dominant bacteria linked to bacterial vaginosis or BV, which “could rapidly metabolize and break down the active form of the drug,” the researchers wrote.
Since BV is capable of increasing inflammation, impairing wound healing, disrupting the vaginal wall and women in Sub-Saharan Africa have a high prevalence rate of BV, it is highly known to increase the risk of HIV.
Women who had healthier vaginal bacterial compositions, dominated by bacteria Lactobacillus, exhibited three times higher protection against HIV than the women with a different dominant vaginal bacteria composition.
An article written by Khalil G. Ghanem and Susan Tuddenham of the Johns Hopkins University School of Medicine questions if it would be possible to alter the microbiome to improve the performance of the vaginal gel. Approximately 60 percent of women who are diagnosed with BV will experience another bout one year after treatment.
The study was published in the journal Science on June 02, 2017.