The link between bacterial vaginosis and HIV

Bacterial vaginosis (BV) is the most common reproductive tract infection in women of childbearing age (1, 4), occurring even more frequently than thrush. A 2009 study (1) by the Universities of Carolina (US) and Yaoundé (Cameroon) found BV was prevalent in as many as 70% of test subjects who visited clinics for sexual health services. In the broader female population however, it is estimated that between 20-50% of women (2, 3, 4) suffer from BV.

A recent study (1) found BV increases a woman's risk of acquiring HIV by as much as 60%. In South Africa, where 5.7 million people are believed to live with HIV (8), the high incidence of bacterial vaginosis adds to women's vulnerability of acquiring the virus.

A recent study estimated 15% of HIV infections may be attributed to BV in a population of women with a BV prevalence of 30% (1). In a country like South Africa with a high incidence of HIV, researchers estimate that BV may be responsible for more than a third (31%) of HIV infections among the female population (2).

The dangers posed by even small abrasions

"The prevalence of BV and the heightened associated risk of HIV infection could have dire consequences," says Dr Sumayya Ebrahim, a Johannesburg-based gynaecologist in private practice.

The inflammation caused by the BV infection results in micro abrasions - small microscopic tears - in the lining of the vaginal wall (7). When exposed to HIV, these micro abrasions become easy access points for HIV to enter the body (7).

"Women can manage their risk of contracting HIV by making sure they seek prompt treatment for all other vaginal infections," says Ebrahim.

Interestingly, a 2005 study also suggests that the treatment of BV and other interventions which promote normal vaginal bacteria warrant attention for HIV prevention among South African women (1, 2).

Early and effective treatment of BV can help women manage their risk for HIV. The main symptom of BV is abnormal vaginal discharge (5), typically a milky or pearly grey mucus with a strong fishy odour. Although vaginal discharge is a normal and natural part of womanhood, it is considered abnormal when it occurs in large amounts, is thicker than usual, has an offensive odour and is associated with other symptoms, such as pain or itchiness.

BV is caused by an imbalance in the ecology of the normal vaginal flora due to the rapid growth of several kinds of bacteria that normally live in the vagina. Small organisms, called Lactobacilli, help keep the pH at the right level, while using antibiotics, soaps and even having sex can leave the vagina more alkaline, thereby encouraging bacterial growth. BV may also be associated with douching and smoking. There also appears to be a link between BV and times of stress in a woman's life (6).

For further information on bacterial vaginosis go to www.health24.com

References:

(1) Atashili, J., Poole, C., Ndumbe, P.M., Adimora, A.A. and Smith, J.S. Bacterial vaginosis and HIV acquisition: A meta-analysis of published studies. AIDS. 2008 July 31: 22(12): 1493-1501
(2) Myer, L., Denny, L., Telerant, R., De Souza, M., Wright Jr, T.C. and Kuhn, L. Bacterial vaginosis and susceptibility to HIV infection in South African Women: A nested case-control study. The Journal of Infectious Diseases. 2005; 192:1372-1380
(3) Schwebke, J.R. Abnormal vaginal flora as a biological risk factor for acquisition of HIV infection and sexually transmitted diseases. The Journal of Infectious Diseases. 2005; 192:1315-1317
(4) Hillier, S.L., Holmes, K.K. Bacterial vaginosis. In: Holmes, K.K., Sparling, P.F., Mardh, P.A., et al., eds. Sexually transmitted diseases. 3rd ed. New York: McGraw-Hill, 1999:563-586
(5) The Centres for Disease Control and Prevention. Sexually Transmitted Diseases Treatment Guidelines. 2006. MMWR 2006; 55 [RR-11]: 50-52
(6) Health24. Vaginal discharge. April 2010. www.health24.com/medical/Head2Toe/777-778-783,11944.asp
(7) Ebrahim, S. Telephonic interview with practicing gynaecologist. 14/07/2010
(8) Health24. A TB/HIV researcher's story. July 2010. www.health24.com/medical/Condition_centres/777-792-814-1536,57089.asp