BV: the STI you have when you don’t have an STI?
Although Bacterial Vaginosis (BV) is globally the commonest vaginal infection in women of reproductive age, very little is known about the disease. Importantly, its cause and whether it is sexually transmitted is unknown, according to the Sexual Health Unit’s Dr Catriona Bradshaw, principal researcher of the WOW (Woman on Woman’s Health) project.
“It’s a very common disease. We see prevalences of 10% in Australian women attending general practices but this rises to 30% within the lesbian population – and we don’t know why. We wonder if that is related to the fact that it is more easily transmissible between women than between men and women.”
The WOW study is focusing on BV in the lesbian community. Since March 2010, WOW has recruited more than 300 participants. The recruitment drive has been innovative: festivals like Mardi Gras and Midsumma, advertising on lesbian Internet dating sites and other gay media. Participants commit to regularly posting in self-administered swabs during the two-year study. The swabs are tested for BV and, if diagnosed, participants receive treatment.
“A key objective of our BV research is to determine what factors or behavioural practices are associated with the development of BV in women and their female partners and this will help us understand whether it is an STI. If it’s an STI, this has enormous implications for improving our management of this common infection and for prevention,” Dr Bradshaw says.
While BV is still not considered an STI, it certainly co-exists with all the other STIs, she says. “We see it in sex workers, we see it other groups that have a high prevalence of STIs often due to factors such as poor access to healthcare, so BV is common in women in developing countries and in indigenous populations. The exceptions to this are lesbians, who don’t have a high prevalence of STIs.”
Another reason for focusing on women is that there is no diagnostic method that can be applied to men – so the BV status of men remains a mystery, much like the disease itself. What is known is that BV can have serious health implications. In pregnancy it increases the risk of miscarriage, pre-term delivery and low birth weight, and it also increases the risk of sexual acquisition of HIV and other STIs.
Why has BV remained under the STI radar? Dr Bradshaw says that in previous trials, after treatment with antibiotics, up to 50% of women got the disease again within six months. “But when we give those antibiotics to male partners in randomised trials it doesn’t seem to make any difference to the recurrence rates in women. So usually, if a disease is sexually transmitted, if you treat the woman and you treat the man, you eradicate it from a relationship. So those treatment trials were used as evidence that this is not a sexually transmitted disease.” However, Dr Bradshaw suggests that perhaps the treatments used were not sufficiently effective to eradicate BV in either women or men, given that we don’t actually know the cause. “We might not be treating men or women correctly – we might be partially treating them but not completely treating them.”
Caption: The WOW (Women on Women’s Health) website.