Authors: Martha Powell, Future Science Group
A new study has been the first to report a vaccine demonstrating protection against gonorrhoea. This follows news last week where the WHO warned of increasing antibiotic resistance in the disease, including three cases untreatable with current antibiotics.
The study, published in the Lancet, investigated the effectiveness of the outer membrane vesicle meningococcal B vaccine (MeNZB) against gonorrhoea, following surveillance data suggesting the meningococcal vaccine may affect gonorrhoea incidence.
The researchers assessed approximately 15,000 young people aged 15–30 who attended sexual health clinics in New Zealand. The retrospective case-control study included participants eligible to receive MeNZB who were diagnosed with either gonorrhoea, chlamydia or both.
The team collected demographic data, data from the sexual health clinic and records from the National Immunization Register for each patient, comparing individuals with confirmed Neisseria gonorrhoeae isolates with those who had a positive chlamydia test only. Overall the researchers analyzed 14,730 cases and controls – 1241 incidences of gonorrhoea, 12,487 incidences of chlamydia and 1002 incidences of co-infection.
By estimating odds ratios comparing disease outcomes in vaccinated vs unvaccinated participants, the team discovered that vaccinated individuals were significantly less likely to have gonorrhoea compared with controls. In addition, after adjustment for factors such as ethnicity and deprivation, the researchers estimated the vaccine effectiveness of MeNZB against gonorrhoea to be 31%.
The team suggested that the vaccine provides ‘cross-protection’ as a result of the relation between the causative agents of meningitis and gonorrhoea. This is the first time a vaccine has been demonstrated to provide any protection against gonorrhoea, and the team hope these findings could inform future vaccine development.
Author, Helen Petousis-Harris, from the University of Auckland (New Zealand), commented: “This is the first time a vaccine has shown any protection against gonorrhoea. At the moment, the mechanism behind this immune response is unknown, but our findings could inform future vaccine development.”
Find out more about other strategies currently under development to combat drug-resistant gonorrhoea in our exlusive report ‘Gonorrhoea – the current antibiotic pipeline and the need for new drugs’.
Sources: Petousis-Harris H, Paynter J, Morgan J et al. Effectiveness of a group B outer membrane vesicle meningococcal vaccine against gonorrhoea in New Zealand: a retrospective case-control study. Lancet. doi:10.1016/S0140-6736(17)31449-6 (2017) (Epub ahead of print); www.bbc.co.uk/news/health-40555702#