If you were born before 2015, you have no protection against the type of meningitis behind the UK outbreak
Nobody who grew up before September 2015 received routine vaccination against meningococcal group B — the serogroup responsible for the majority of bacterial meningitis cases in Europe — and that includes you, your children unless they’re very young, your parents, and your doctor. Most people don’t know this, because they assume the meningitis vaccines they or their children received covered it. They didn’t: those vaccines (MenC, later MenACWY) cover serogroups A, C, W, and Y, but not B.
This week, two people died and twenty cases — nine lab-confirmed — were reported in a MenB outbreak in Canterbury, Kent, linked to a nightclub and the University of Kent(Agency 2026; News 2026). The spread has been described as “explosive” and “unprecedented” by health officials, and the outbreak has now been declared a national incident after a related case was identified outside Kent. The students affected are 18 to 24 — born squarely in the decade before a MenB vaccine existed — but the vulnerability isn’t generational in any meaningful sense. Every adult alive today has the same MenB vaccination status: none.
If you find this alarming — and you should — share this article with your local health authority, your MP or elected representative, your national health ministry. The vaccine exists. The evidence is there. What’s missing is the policy decision to use it beyond infants.
The reason this gap exists in the first place — and why it took thirty years longer to develop a MenB vaccine than a MenC vaccine — is one of the more interesting stories in modern vaccinology.
1 The capsule problem
Most bacterial vaccines work by training the immune system to recognise the sugar coating — the polysaccharide capsule — that surrounds the bacterium. Vaccines against meningococcal serogroups A, C, W, and Y were all developed this way: researchers isolated the capsule, presented it to the immune system, and it worked. The MenC vaccine arrived in the UK in 1999, and MenACWY conjugate vaccines followed.
Meningococcal group B was the exception. Its polysaccharide capsule is made of polysialic acid — a molecule that is structurally nearly identical to molecules found on the surface of human neurons, particularly during fetal brain development. If you made a vaccine that taught the immune system to attack MenB’s capsule, you risked teaching it to attack the body’s own nervous system. The traditional approach was not just ineffective — it was potentially dangerous.
This wasn’t a failure of effort. Researchers understood the problem clearly by the 1980s and spent the next two decades trying to solve it. MenB was the most common cause of bacterial meningitis in Europe and the second most common in North America, killing and disabling thousands of young people every year, and there was simply no way to vaccinate against it.
2 Reverse vaccinology: sequencing your way to a vaccine
The breakthrough came from an entirely different direction. In 2000, Rino Rappuoli and his team at what was then Chiron (later Novartis, now GSK) decided to skip the capsule entirely. Instead, they sequenced the complete genome of a MenB strain(Pizza et al. 2000) and computationally identified every protein the bacterium might display on its surface — 570 candidates in total — then expressed each one in the lab, tested which provoked bactericidal antibodies, and narrowed the list down to a handful of targets that worked across multiple MenB strains.
The result was Bexsero (4CMenB), which targets four surface proteins: factor H binding protein (fHbp), Neisserial Heparin Binding Antigen (NHBA), Neisseria adhesin A (NadA), and an outer membrane vesicle containing the porin PorA from a New Zealand epidemic strain. None of these is the capsule; all of them are proteins the bacterium needs to survive in blood and invade tissue, so the vaccine targets the bacterium’s weapons rather than its armour.
This genome-first approach — dubbed “reverse vaccinology” because it starts from the DNA sequence rather than the pathogen’s surface — was genuinely new, and Bexsero was its first proof of concept(Rappuoli 2000). Rappuoli’s team published the method in 2000; the approach has since been applied to Group B Streptococcus and Staphylococcus aureus, and the underlying logic contributed to the speed of COVID-19 vaccine development two decades later.
3 Thirteen years from genome to approval
Even with the breakthrough, progress was slow by pandemic standards: the genome was sequenced in 2000, Bexsero received European Medicines Agency approval in January 2013, and the UK — the first country in the world to add it to a routine national immunisation schedule — didn’t begin its infant programme until September 2015.
The results since then have been substantial. Real-world UK data show 83% vaccine effectiveness against any MenB strain, 94% against strains predicted to be vaccine-preventable, and a 75% reduction in MenB cases in vaccine-eligible children since the programme began(Ladhani et al. 2020). Over three million doses have been administered with no additional safety concerns beyond the expected reactogenicity (fever, injection site reactions).
But the programme only covers infants. In the UK, the schedule is two doses at 8 weeks and 16 weeks, with a booster at 12 months. That means protection extends to children born from September 2015 onward. Everyone else — every adult, every teenager, every child born before that date — was never routinely offered MenB vaccination.
4 The gap is not generational — it is universal
It is tempting to describe this as a generational gap, since the Kent outbreak is hitting university-age students — 18 to 24 year olds born between 2001 and 2007, squarely in the window before MenB vaccination existed. But the gap is much wider than that. No adult alive today received routine MenB vaccination as a child, because there was no MenB vaccine to give. A 40-year-old and a 20-year-old have the same MenB vaccination status: none.
The reason older adults don’t usually get meningococcal disease at the same rate as teenagers isn’t vaccination — it’s natural immunity acquired through asymptomatic carriage. About 10% of the adult population carries Neisseria meningitidis in the nasopharynx at any given time without becoming ill, and this carriage builds antibodies over years of exposure.
But here’s the part that public health policy tends to get wrong: the adolescent risk peak is not fundamentally about age. It’s about behaviour. University freshers, nightclub crowds, shared dormitories, kissing, passing drinks around — these are the transmission conditions that create outbreaks, and the Kent cluster is a textbook example: Club Chemistry nightclub, University of Kent halls. A 35-year-old who frequents crowded nightlife venues has more meningococcal exposure risk than a 19-year-old who stays home. Framing vaccination policy in age brackets — infants get it, everyone else doesn’t — misses this entirely.
What age does contribute is the immunological starting point. Teenagers and young adults haven’t yet accumulated enough years of asymptomatic carriage to build robust natural immunity, so when they hit the high-exposure environments, they’re both more exposed and less protected. But the exposure side of that equation applies to anyone whose social behaviour puts them in close-contact settings — regardless of their age, and regardless of whether health policy considers them a target group.
That natural carriage-based immunity is also variable: it depends on which strains you happened to carry, and may be inadequate against novel ones. For anyone with a compromised immune system — including the millions of people living with post-infectious conditions like ME/CFS and Long COVID — the assumption that asymptomatic carriage built adequate protection may not hold at all.
5 What Bexsero does and does not cover
Even Bexsero is not a complete solution. Because it targets specific surface proteins rather than the capsule, its effectiveness depends on whether a given MenB strain expresses enough of those proteins for vaccine-induced antibodies to recognise it(Parikh et al. 2016). Coverage varies substantially by strain lineage(Vogel et al. 2013; Hong, Deghmane, and Taha 2018):
- Clonal complex cc41/44: ~94% coverage
- Clonal complex cc32: ~96% coverage
- Clonal complex cc269: declining — from 73% in 2007–08 down to 53% by 2014–15
The Kent outbreak strain has been confirmed as MenB, but the specific clonal complex has not been publicly identified. Prof Andrew Pollard of the Oxford Vaccine Group noted in response to the outbreak that “the first question on vaccination is whether this B strain is covered by the vaccine, as this isn’t always the case.”(Centre 2026)
A second MenB vaccine exists: Trumenba (Pfizer), which targets two variants of factor H binding protein and has higher predicted MenB-specific coverage (90% vs Bexsero’s 67%). It received EMA approval in 2017 and is technically licensed across all EU member states, but in practice it is far harder to obtain than Bexsero in most European countries — pharmacies rarely stock it, no country includes it in a routine schedule, and it would typically need to be special-ordered through a GP. In the US, where Trumenba is part of the routine adolescent schedule, it costs roughly $200–230 per dose. The two vaccines are complementary rather than interchangeable: UKHSA used Trumenba for the first time in 2023 to control a nursery outbreak where the strain was poorly covered by Bexsero(Willerton et al. 2026), demonstrating that each vaccine catches strains the other misses. Together they would cover an estimated 95% of circulating MenB strains — and by extension, a similar proportion of cases — but no country currently uses both routinely.
6 What this means in practice
If you are an adult in Europe, you are almost certainly unvaccinated against MenB. You may have received MenC (introduced in 1999 in the UK, later elsewhere) or MenACWY (added to many European schedules from 2015 onward), but neither covers serogroup B.
The situation across Western Europe is remarkably uniform in this regard. The UK and Ireland include MenB in their routine infant schedules, and Italy does as well — but France, Germany, Belgium, and Luxembourg do not. Germany’s STIKO recommends Bexsero only for defined high-risk groups (complement deficiency, asplenia). France’s vaccination advisory board has not recommended routine inclusion at all. Belgium’s Superior Health Council takes a middle path, recommending individual-level decision-making in consultation with a physician but stopping short of adding it to the routine schedule. Luxembourg follows the same non-routine approach(Disease Prevention and Control 2026; Findlow and Borrow 2019). In practical terms, this means that across the entire Benelux, France, and Germany — roughly 200 million people — nobody is routinely vaccinated against MenB unless they specifically sought it out and paid for it themselves.
Bexsero has been EMA-approved since January 2013 and is licensed across all EU member states. Unlike Trumenba, it is widely stocked in pharmacies and readily available by prescription — any GP can prescribe it. In Belgium, it costs approximately €80–90 per dose, with two doses required at least one month apart (typically given at 0 and 2 months). In the UK, it can be purchased privately for around £100 per dose. Part of the reason for the higher price, compared with older meningococcal vaccines, is the manufacturing complexity: traditional polysaccharide-conjugate vaccines like MenACWY involve growing the bacterium and harvesting its capsule, which is relatively straightforward. Bexsero requires producing four separate recombinant proteins plus outer membrane vesicles from a specific reference strain, each with its own expression system, purification, and quality control — a fundamentally more elaborate process that reflects the scientific difficulty of the problem it was designed to solve.
For anyone considering vaccination — whether because of the Kent outbreak, upcoming UK travel, or simply because they’ve just learned they have no MenB protection — the timeline is worth understanding. Antibody responses peak about two to four weeks after each dose. After the first dose, seroprotective antibody levels are reached by roughly 60–80% of adults within a month, depending on which of the four antigens you measure. After the second dose, that rises to 85–95%. So protection isn’t instant, but it builds meaningfully within weeks: someone who gets their first dose today and their second a month later would have full two-dose immunity roughly six to eight weeks from now. The Kent emergency deployment is giving students single doses precisely because partial protection within weeks is better than waiting months for a complete series while an outbreak is active.
Following the Kent outbreak (Health and Care 2026), the UK Secretary of State for Health has asked the JCVI (Joint Committee on Vaccination and Immunisation) to re-examine meningitis vaccine eligibility more broadly. Whether this leads to extending routine MenB vaccination beyond infants — and whether other European countries follow — remains to be seen.
7 The thirty-year lesson
From the 1980s, when the capsule mimicry problem was clearly understood, to 2013, when Bexsero was finally approved, three decades passed during which the most common form of meningitis in Europe had no vaccine. The breakthrough that ended that gap — reverse vaccinology — did not come from incremental improvement of the old approach. It came from abandoning the old approach entirely and starting from the genome.
That methodological shift — from isolating surface chemistry to reading the genome directly — has since been applied to Group B Streptococcus, Staphylococcus aureus, and contributed to the rapid development of COVID-19 vaccines two decades later. But the practical consequence of the original thirty-year delay is something the Kent outbreak has brought back into focus: every adult alive today grew up without MenB protection, and most don’t know it. Two people are dead and twenty cases have been reported because a bacterium found an unvaccinated population in a high-contact social setting.
The UK is now re-examining eligibility through the JCVI. The rest of Europe should not wait for its own outbreak to do the same. The vaccine has been available for over a decade, with real-world effectiveness data from millions of UK doses, and the cost of inaction is measured in preventable deaths and lifelong disability. Health ministries across the EU — in France, Germany, Belgium, the Netherlands, and beyond — have the evidence they need to extend MenB vaccination beyond infancy. The question at this point is not whether the science supports it, but how many more outbreaks it will take before the policy catches up.