Can Some Vaginal Bacteria Protect Women From HIV Infection?

SCIENCE!!!—According to an article published last week in the research journal mBio, a team of researchers has come to the conclusion that a certain form of bacteria which can be found in some women's vaginal fluids can actually prevent that person's infection with HIV by essentially "trapping" the HIV virus and preventing it from reaching the body's immune system, where it would typically multiply and cause the symptoms commonly described as Acquired Immune Deficiency Syndrome, or AIDS. "If HIV can’t get to the cells they want to infect, you won’t have transmission," researcher Sam Lai told Daily Beast correspondent Carrie Arnold regarding the study in which he took part. "These microbes act as a barrier, which is what a condom does. So I like to think of them as a biological condom." According to the Daily Beast article, Lai and his team's researches didn't start with the bacteria, but rather with mucus, whose main ingredient, the protein mucin, has "long, branched projections that enable it to stick to viruses, bacteria, and other particles like Velcro." And since mucus coats many of the orifices of the body where infections are most likely to enter, mucin and other ingredients are a primary barrier to viruses and other infectious material. "We like to think of mucus as the first line of defense. One of the reasons we don't get sick that often is that the mucus is already doing a really good job," Lai said. But Lai and his fellow researchers realized that it's not just mucus that the body uses to protect itself; it also allows for the growth of protective bacteria which can "prevent harmful microbes from gaining a foothold in the body," Arnold wrote. "These microbes are tremendously dynamic, varying dramatically from person to person, and even within the same person over time." But while researchers have long known that a type of bacterium known as Lactobacillus is common in the fluids of a healthy vagina, Lai and his team found that a particular strain of Lactobacillus called Lactobacillus crispatus (L. crispatus) generated more lactic acid within the vagina, which in turn lowered the pH of the vaginal fluids and therefore did a better job of preventing HIV infection, with L. crispatus generally trapping more than 90 of the HIV virus particles to which it was exposed. "I was really excited to see this study," said Temple University reproductive epidemiologist Deborah Nelson, who was not involved in the study. "It opens the door to the idea that women could alter the microbes in their genital tract to prevent HIV infection either before or after they might have been exposed." The Daily Beast article makes it clear that this research is still in its early stages, but noted that "the work opens the door to a new type of condom that can potentially be created using a probiotic supplement or suppository and used by a woman without requiring the consent or approval of her partner." Needless to say, such a development would be a real boon for adult content production.