Gonorrhoea vaccine

Gonorrhoea is an infection caused by the bacterium Neisseria gonorrhoeae that mainly spreads through sex. It is passed on through vaginal, oral, and anal sex, and anyone can catch it. The vaccine used to protect against gonorrhoea in the UK was originally developed to protect against the bacteria that cause group B meningococcal meningitis (Men B), but it also offers some protection against gonorrhoea. 

The vaccine will be used in a targeted programme, starting in August 2025, and delivered through sexual health services. Primarily, the vaccine will be offered to men who have sex with other men who have a recent history of multiple sexual partners, or who have recently had a sexually transmitted infection.  It will also be available to others who are also at a high risk of contracting gonorrhoea. 

The vaccine is estimated to be 32 – 42% effective against gonorrhoea. Although vaccination would be expected to reduce the chance of becoming infected with gonorrhoea, it would not eliminate the possibility completely. The main benefit of the vaccination programme is expected to be at a community level, with a significant reduction in the number of cases overall in the UK, as well as helping tackle the increasing levels of antibiotic resistant strains of the disease

It takes at least 2 weeks from the second dose for your body to produce enough antibodies to give you a good level of protection.

The Joint Committee on Vaccination and Immunisation (JCVI) suggested that the programme should primarily target men who have sex with men who are at an increased risk of becoming infected. These risk criteria may include:

• a recent history of gonorrhoea or other bacterial STI diagnosis, individuals should also be offered vaccination after a gonorrhoea diagnosis (whether symptomatic or asymptomatic)
• reporting high-risk sexual behaviours with multiple partners during sexual health screening and assessment

Any offer of vaccination should be based on individual risk assessment by a sexual health clinical professional.

Like all vaccines, the vaccine to protect against gonorrhoea can cause side effects, although not everybody gets them.  The vaccine used in the UK is called Bexsero. Side effects may include:

Very common, these may affect more than 1 in 10 people:

• pain at the injection site resulting in inability to perform normal daily activity,
• painful muscles and joints,
• nausea,
• generally feeling unwell,
• headache.

Very common side effects that may affect more than 1 in 10 people, that were reported in all age groups:

• pain/tenderness at the injection site
• redness of the skin at the injection site
• swelling of the skin at the injection site
• hardness of the skin at the injection site.

As with any vaccine, medicine or food, there is a very small chance of a severe allergic reaction (anaphylaxis). Anaphylaxis is different from less severe allergic reactions because it causes life-threatening breathing and/or circulation problems. It is always extremely serious but can be treated with adrenaline. Healthcare workers who give vaccines know how to do this.

In the UK between 1997 and 2003 there were a total of 130 reports of anaphylaxis following ALL immunisations. Around 117 million doses of vaccines were given in the UK during this period. This means that the overall rate of anaphylaxis is around 1 in 900,000.

If you are concerned about any reactions that occur after vaccination, consult your doctor. In the UK you can report suspected vaccine side effects to the Medicines and Healthcare products Regulatory Agency (MHRA) through the Yellow Card Scheme.

You can also contact the MHRA to ask for data on Yellow Card reports for individual vaccines. See more information on the Yellow Card scheme and monitoring of vaccine safety.

Bexsero contains different proteins taken from group B Neisseria meningitidis bacteria.

Apart from these active ingredients (the antigens), the vaccine contains very small amounts of these ingredients:

• Aluminium, which strengthens and lengthens the immune response to the vaccine
• salt (sodium chloride)
• sugar (sucrose) and an amino acid called histidine, both used as acidity regulators. (Amino acids are the building blocks of proteins.)

The vaccine may also contain traces of these products used during the manufacturing process:

• kanamycin, an antibiotic used in the production process to stop bacteria growing and contaminating the vaccine

Latex may be used in the packaging of Bexsero.

Men B as a gonorrhoea vaccine

Neisseria meningitidis (the bacteria that causes meningitis) and Neisseria gonorrhoeae (the bacteria that causes gonorrhoea) are closely genetically related, with between 80 to 90% similarity.  This similarity gives the potential for cross-protection from some meningococcal B vaccines against Neisseria gonorrhoeae.

In 2004, an outbreak of Men B in New Zealand prompted a universal offer of a meningitis B vaccine for children and young adults. Studies showed that after this programme was implemented, there was a decline in gonorrhoea rates in adolescents and young adults who were eligible for this vaccine, suggesting cross protection. A case-control study was carried out within sexual health clinics in New Zealand in those who had been eligible to receive the vaccine, which estimated a vaccine effectiveness of 31% against gonorrhoea.

Cost effectiveness of a gonorrhoea vaccine programme

The JCVI reviewed cost-effectiveness models from Imperial College and UKHSA exploring different vaccination strategies for gay, bisexual, and other men who have sex with men (GBMSM) aged 15–65. Because this modelling predated confirmed vaccine effectiveness data for Bexsero, it used a range of estimated effectiveness values (20%, 40%, 80%) and also incorporated data from a MeNZB study.

Four vaccination scenarios were modelled:

1. Before sexual debut (adolescents)
2. On diagnosis (after gonorrhoea diagnosis)
3. On attendance (all GBMSM at sexual health clinics)
4. According to risk (diagnosed cases + those reporting high sexual activity)

Key findings:

• Adolescent vaccination uses the most doses but targets the lowest-risk individuals.
• On-diagnosis uses the fewest doses but targets high-risk individuals.
• According to risk and on attendance approaches had the greatest impact on reducing gonorrhoea cases.
• Vaccination on attendance offers marginally greater health benefit than according to risk, but at significantly higher cost and dose use.

For more information on the JCVI independent report, please visit here.