Gonorrhea cases are on the rise in many populations, and they also bring an added problem: antibiotic-resistant strains. If measures are not taken to prevent cases and effective treatment, it can become a serious health problem. Faced with this situation, scientists are studying ways to stop it. Specifically, three recently published studies propose the use of the vaccine for meningitis against gonorrhea.
What is gonorrhea?
Gonorrhea is a sexually transmitted disease (STD) that can affect both men and women and is caused by a bacterium: Neisseria gonorrhoeae . This bacteria can be passed from an infected person to a healthy person through close contact and body fluids, with semen and vaginal fluids being the most common.
Although some infected people are asymptomatic, it is necessary to treat the infection and eliminate it from the body, because it not only poses a risk to sexual partners , but also increases one’s own risk of developing other sexually transmitted diseases such as HIV .
What treatments exist for gonorrhea?
As it is a bacterial infection, the standard and most effective treatment is the use of antibiotics . In most cases, the infection clears up, but a test needs to be repeated after three months to confirm that there are no traces of the infection even in the absence of symptoms.
The problem appears when this bacterium is resistant to antibiotics , which makes it immune to treatment and the infection persists. Superbugs , as bacteria multi-resistant to various types of antibiotics are known, are a serious health problem and if we do not regulate the use of antibiotics it will only get worse.
Antibiotic-resistant strains of Neisseria gonorrhoeae , like many other bacteria, are being detected with increasing frequency and become an untreatable disease, as there is no vaccine or effective alternative treatment against gonorrhea.
The development of molecular and specific diagnostic measures may help develop the gonorrhea vaccine, but until then, the meningitis vaccine may be a solution.
Partial protection with a non-specific vaccine
Three studies recently published in The Lancet have collected evidence from populations in the United States (USA), Australia and England on the effect of the meningitis vaccine in preventing gonorrhea .
The study carried out in the US made a retrospective analysis (looking at the medical records of more than 100,000 patients who contracted gonorrhea and their vaccination records) and showed that the meningococcal vaccine turned out to be 40% effective against gonorrhea .
The Australian study was conducted in children, adolescents and young people who received the meningococcal vaccine and were followed for two years to identify if they contracted gonorrhea infection. The efficacy of this vaccine to prevent gonorrhea was 33% in adolescents and young people , and up to 100% in children .
Finally, the study carried out in England focused on evaluating whether the meningitis vaccine would be cost-effective , paying special attention to what the researchers define as subjects at risk. The study concludes that it would be cost-effective , despite being 31% effective , when applied as a complementary measure to other treatments and preventive activities.
Why does the vaccine protect against meningitis?
The fact that the meningitis vaccine provides partial protection against gonorrhea lies in the pathogen causing each of the diseases and the design of the vaccine.
On the one hand, we have the bacterium Neisseria gonorrhoeae that causes gonorrhea and for which there is no vaccine. On the other hand , we find Neisseria meningitidis , the bacteria that causes meningitis . Both are diplococci that belong to the same genus of bacteria, which includes gonococcus and meningococcus .
The meningitis vaccine, also known as the meningococcal vaccine , is designed to activate an immune response that reacts against a foreign molecule from the bacteria. This molecule bears some similarity to that present in N. gonorrhoeae .
For this reason, receiving the N. meningitidis vaccine prepares our body with an arsenal of defenses (antibodies and specific cells) capable of recognizing the molecule contained in the vaccine.
If that molecule reappears, even in a similar way, on a different bacterium ( N. gonorrhoeae ), the immune system will make no distinction and will eliminate it, albeit with somewhat reduced efficiency .
Although more studies are still needed to evaluate the effectiveness, these investigations represent a clear advantage in a situation that can be critical in a short period of time.
References:
Abara et al. 2022. Effectiveness of a serogroup B outer membrane vesicle meningococcal vaccine against gonorrhoea: a retrospective observational study. Lancet Infect Dis. doi: 10.1016/S1473-3099(21)00812-4
Shen and Zang. 2022. Feasibility of gonorrhoea vaccination among men who have sex with men in England. Lancet Infect Dis. doi: 10.1016/S1473-3099(21)00760-X
Wang et al. 2022. Effectiveness and impact of the 4CMenB vaccine against invasive serogroup B meningococcal disease and gonorrhoea in an infant, child, and adolescent programme: an observational cohort and case-control study. Lancet Infect Dis. doi: 10.1016/S1473-3099(21)00754-4
