Analysis uncovers why Kent meningitis B outbreak was so dangerous
Two teenagers died and nine others were hospitalised following an outbreak in Canterbury in March
Last updated 17 hours ago
Scientists have uncovered why the bacteria that caused the deadly meningitis B outbreak in Kent was so dangerous.
Analysis has shown the bacteria which caused the infection borrowed genetic traits from less harmful bacteria found naturally in the throats of many healthy people.
The March 2026 outbreak was liked to a nightclub in Canterbury with 21 people diagnosed with invasive meningococcal disease (IMD) in one week.
Two teenagers died and nine required intensive care.
Experts at the UK Health Security Agency (UKHSA) and the University of Oxford used bacterial genome sequencing to understand why the outbreak was so severe.
They found 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 treats 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 how it was recognised by the immune system.
According to the UKHSA these invasive strains can emerge suddenly and are unpredictable, meaning similar outbreaks are likely to occur again.
It may also explain why it did not continue to spread.
Dr Charlene Rodrigues, consultant in pathogen genomics at UKHSA, said: “This investigation shows just how quickly and dramatically these bacteria can change, sometimes acquiring new traits from harmless bacteria circulating nearby, that make them more likely to cause disease.
“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.
“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.