By Amelia Grant | LONDON – 2025/05/26 22:24:10

The fight against gonorrhea could be getting a boost from an unexpected source: vaccines designed to prevent meningococcal disease. Emerging research suggests that certain meningococcal B (MenB) vaccines might reduce the risk of contracting gonorrhea. This has led public health officials in England to begin offering the vaccine to individuals at higher risk of gonorrhea exposure.

Gonorrhea remains a significant public health concern. In the United states alone, over 600,000 cases were diagnosed in 2023. The centers for Disease Control and Prevention (CDC) estimates the actual number of annual cases to be closer to 1.6 million, due to the high percentage of asymptomatic infections.

The Challenge of Gonorrhea Prevention

While gonorrhea has been treatable for nearly a century, the effectiveness of available medications is dwindling. The bacteria responsible for gonorrhea have developed resistance to multiple classes of antibiotics. As early as the 1940s, resistance to sulfanilamides emerged, followed by resistance to penicillins and tetracyclines in the 1980s. In 2007, the CDC ceased recommending fluoroquinolones, leaving cephalosporins as the primary effective treatment option. This increasing resistance underscores the importance of effective prevention strategies.

Existing prevention methods include condoms,which provide a physical barrier against the exchange of bodily fluids,and Doxy PEP,a post-exposure prophylaxis involving an oral antibiotic taken after unprotected sex. Studies have shown Doxy PEP to be approximately 50% effective against gonorrhea and 80% effective against chlamydia and syphilis.

Currently, there is no specific vaccine for gonorrhea, which is caused by the bacterium Neisseria gonorrhoeae. Though, the vaccine against meningococcal meningitis, caused by the related bacterium Neisseria meningitidis, has garnered attention. Scientists have been investigating whether meningococcal B (MenB) vaccines offer cross-protection against gonorrhea, and recent research suggests this may be the case.

While randomized clinical trials are necessary, the findings of this systematic review and meta-analysis highlight the potential effectiveness of OMV-based vaccines in terms of gonorrhea prevention.

Promising Research on Existing Vaccines

Two recent reviews, conducted by researchers in Hungary and Greece, have indicated that the incidence of gonorrhea was lower among individuals who received the 4CMenB vaccine compared to those who were unvaccinated or received other meningococcal vaccines.

A key component of the 4CMenB vaccine is OMV, or outer membrane vesicles. These vesicles are naturally released by the bacteria that cause meningococcal meningitis and gonorrhea. OMV mimic the exterior of the bacteria, resembling a pathogen without being infectious, making them an effective vaccine delivery mechanism.

The Hungarian researchers analyzed seven studies, six of which focused on the 4CMenB vaccine. Their analysis revealed a pooled vaccine effectiveness (VE) of 38% against gonorrhea infection. When they specifically examined the 4CMenB vaccine studies, the pooled VE increased slightly to 41%.

Similarly, the Greek researchers analyzed nine studies, eight of which investigated the 4CMenB vaccine.They reported a pooled VE of 30% against gonorrhea. The researchers concluded that while further randomized clinical trials are needed, the existing evidence suggests the potential effectiveness of OMV-based vaccines in preventing gonorrhea.