Gonorrhoea is the second most common nationally notifiable sexually transmitted infection (STI) in the US. It affects both men and women, with young people and racial minorities bearing a disproportionate burden. Gonorrhoea is treated using antibiotics, but its increasing resistance to antimicrobial treatment may present a challenge in the future. This possibility has led researchers to consider other methods to prevent gonorrhoea infection, including vaccination. Although there is currently no vaccine that specifically prevents gonorrhoea, ecological studies have shown that serogroup B meningococcal vaccines, intended to prevent meningococcal disease, may also confer some protection against gonorrhoea. Recent findings from a study conducted by Abara and colleagues in the US and published in ‘The Lancet Infectious Diseases’ suggest that having a completed meningococcal disease vaccination series was 40% effective against contracting gonorrhoea.

The study examined more than 109,700 teens and young adults (ages 16 to 23 years) from STI surveillance records in New York City and Philadelphia linked to their immunisation registry records. Using this linked dataset, the study authors determined the vaccination status at the infection of gonorrhoea, defined as complete (two doses of the meningococcal disease vaccine), partial (a single dose) or no vaccination. Compared with no vaccination, having a completed or partial meningococcal disease vaccination series were 40% and 26% effective against gonorrhoea, respectively. These findings are in line with a previous study in New Zealand, which found that meningococcal disease vaccination was 31% effective against gonorrhoea.

According to GlobalData epidemiologists, diagnosed incident cases of gonorrhoea in the US have increased by an estimated 11% since 2017, with cases expected to exceed 551,000 by 2027. In addition to this recent US study, previous simulation studies suggest that a vaccine of even modest effectiveness (30% – 50%) and duration of protection (two to four years) could substantially impact gonorrhoea prevention and control. With the implementation of a vaccination programme aimed at preventing gonorrhoea in the US, new cases of gonorrhoea could potentially be lower than projected in the forecast.

These recent findings suggest that a meningococcal disease vaccine could offer cross-protection against gonorrhoea. The genetic similarities between meningococcal disease and gonorrhoea-causing bacteria likely explain this cross-protective effect. More work is needed to confirm these results in other age groups and populations. However, the results of this study provide a promising avenue for gonorrhoea prevention through vaccination, diminishing the future impacts of antimicrobial resistance.