The bacterium Atopobium vaginae (\(A. vaginae\)) is a microbe frequently identified in the female genital tract. It is a component of the complex microbial community residing in the vagina, known as the vaginal microbiome. Individuals often search for information on this organism to determine if they have contracted a sexually transmitted infection (STI). This article addresses that question and explores the organism’s role in bacterial vaginosis (BV).
Is Atopobium Vaginae a Sexually Transmitted Infection?
Atopobium vaginae is not classified as a classic sexually transmitted infection (STI), such as chlamydia or gonorrhea. Classic STIs are caused by the transmission of a specific pathogenic organism foreign to the host’s normal flora. In contrast, \(A. vaginae\) is an opportunistic bacterium, meaning it is a member of the naturally occurring vaginal flora that overgrows when the environment becomes disrupted.
The bacterium’s association with sexual activity is often misunderstood. While sexual factors, including new or multiple partners, can disrupt the vaginal environment, they are considered risk factors for the imbalance, not the direct cause of the condition itself.
The presence of \(A. vaginae\) signifies a state of dysbiosis (ecological imbalance), rather than an infection acquired solely through sexual contact. Medical professionals typically view the condition associated with \(A. vaginae\) as a complex polymicrobial syndrome.
The Role of Atopobium in Bacterial Vaginosis
The presence of Atopobium vaginae is a strong marker for Bacterial Vaginosis (BV), a widespread condition characterized by an imbalance in the vaginal microbiome. In a healthy state, the vagina is dominated by protective Lactobacillus bacteria, which maintain an acidic environment. BV occurs when these protective bacteria are depleted, allowing anaerobic bacteria like \(A. vaginae\) and Gardnerella vaginalis (\(G. vaginalis\)) to proliferate.
\(A. vaginae\) is detected in approximately 80% of women diagnosed with BV and is a major player in the formation of a dense, protective biofilm that adheres to the vaginal epithelial cells. This biofilm, often a synergistic mixture of \(A. vaginae\) and \(G. vaginalis\), shields the bacteria from the host’s immune response and significantly contributes to treatment resistance.
The common symptoms of BV include a thin, grayish-white discharge and a noticeable “fishy” odor, which can be more prominent after intercourse. However, about 50% of people with BV are asymptomatic despite the microbial imbalance.
If left untreated, BV can lead to more serious health concerns. The condition increases the risk of acquiring other sexually transmitted infections (STIs), including HIV, chlamydia, and gonorrhea. BV is also associated with gynecological complications such as Pelvic Inflammatory Disease and adverse pregnancy outcomes, including preterm delivery.
Treatment and Prevention of Recurrence
Treatment for Bacterial Vaginosis typically involves prescription antibiotics. The standard therapeutic regimens include oral or topical metronidazole and topical clindamycin. However, treatment is frequently complicated because \(A. vaginae\) can exhibit resistance to metronidazole and is protected within the polymicrobial biofilm.
Due to this resistance and the persistence of the biofilm, recurrence rates are notably high, with 50% to 80% of women experiencing a return of BV within six to twelve months following antibiotic treatment. For cases that fail standard therapy, alternative treatments like dequalinium chloride or nifuratel may be considered, as they have shown better activity against \(A. vaginae\) and \(G. vaginalis\).
Prevention focuses on maintaining a healthy vaginal microbiome. Avoiding vaginal douching is a primary recommendation, as it can flush out protective Lactobacilli and alter the acidic pH level. Some post-treatment strategies involve the use of vaginal products containing specific Lactobacillus strains or Vitamin C to help re-acidify the environment and promote the re-establishment of a healthy flora.