Scientists reveal why deadly Kent meningitis outbreak was so severe
18-year-old Juliette Kenny and a University of Kent student died in March following an outbreak of meningitis B
Scientists need to be “permanently on the lookout” for genetic changes that can make bacteria more harmful after the deadly meningitis outbreak in Kent, a leading expert has said.
Listen to this article
A team at the UK Health Security Agency (UKHSA) has now uncovered why the bacteria behind the meningitis B outbreak was so dangerous.
Analysis has shown the bacteria borrowed genetic traits from less harmful bacteria found naturally in the throats of many healthy people.
The March 2026 outbreak was linked to a nightclub in Canterbury with 21 people diagnosed with invasive meningococcal disease (IMD) in one week.
Two people died – 18-year-old Juliette Kenny and a University of Kent student – and nine required intensive care treatment.
Read more: Students urged to get meningitis jab ahead of starting university
Read more: 'Sharp' decline in organ donation sees service left in crisis
Experts at the UKHSA and the University of Oxford used bacterial genome sequencing to discover that the bacteria that caused menB picked up small pieces of DNA from other bacteria in a process known as horizontal gene transfer.
This allows bacteria to borrow genetic traits without reproducing.
These changes altered how bacteria interacts with human cells, according to the analysis.
This made it particularly effective at causing severe illness, and may have potentially impacted on how it was recognised by the immune system.
Asked if the same thing could happen again, Professor Robin May, chief scientific officer at the UKHSA, said on Tuesday: “It varies by particular bacteria. In this case, neisseria, which is the group of organisms that can cause meningitis, are actually permanently sampling, if you like, DNA from the environment and they have this capability to do it.
“Obviously, it requires them to pick up a piece of DNA that then helps them become invasive, which is a relatively rare event.
“But I think this is a very important and powerful lesson that we need to be permanently on the lookout for this, because this kind of process is probably happening all the time, and so it’s a very strong reason for us to be maintaining permanent surveillance, to be doing a lot of DNA sequencing to be understanding where and when these kind of events may happen in the future.”
Prof May also urged youngsters to get their menB vaccination when offered one, saying: “If you are eligible for vaccination, this is really, really critical.
“This is university starting week. So if you’re listening to this at university and you haven’t had your two doses and you’re eligible, please do go get those.
“If you’re a parent of a small child and you’re offered infant vaccination, please do take it up. Vaccines remain by far and away the best way to protect yourself from this disease.”
Separately, Dr Charlene Rodrigues, consultant in pathogen genomics at the UKHSA, said the investigation showed just how quickly and dramatically these bacteria can change.
“The fact this outbreak variant was able to spread to so many young people was due to the social environment, a place where lots of close social mixing takes place,” she said.
“Through genomic surveillance and sequencing every cultured case of invasive meningococcal disease in England, we can spot when something unusual is emerging and understand what we’re dealing with in real time.
“What’s particularly interesting about this research is that it suggests the very same genetic changes that made this strain so dangerous may also explain why it hasn’t continued to spread.
“But that is not something we could have predicted and these genetic events can happen again.
“That unpredictability is exactly why continued surveillance and rapid response systems are so important, as are vaccination and public awareness of the signs and symptoms of meningococcal disease.”
Following the Kent outbreak, a one-off menB vaccination programme was launched to protect young people heading to university this autumn.
In July, the Joint Committee on Vaccination and Immunisation (JCVI) also recommended that teenagers should be offered the jab on the NHS around the age of 15, with catch-up programmes for those who would otherwise miss out.
The findings will be presented at the UKHSA’s annual conference in Manchester.