Researchers: bacterium in Kent outbreak picked up genes from other bacteria

According to researchers from the UK Health Security Agency (UKHSA) and the University of Oxford, DNA analysis explains why the March outbreak of meningitis B in Kent was so severe. The bacterium took up part of its genetic material from other bacteria that naturally live in the throats of some people.

According to the researchers, this exchange of genes created a new strain, that is, a variant. It spread among people out at a club and caused severe illness. The information was reported by BBC News.

What happened in Kent

More than 20 young people, mostly students, were infected in the March outbreak. All of them needed hospital treatment, nine were admitted to intensive care, and two died.

The outbreak was linked to a nightclub in Canterbury. It is believed to have started at Club Chemistry, a club popular with students. While it was under way, it was described as “unprecedented” and “explosive”, because so many infections appeared in one place and in a very short time.

How bacteria exchange genes

The phenomenon is called horizontal gene transfer.

For context: meningococci (Neisseria meningitidis) can live in the throats of some healthy people, usually without symptoms, but can cause serious illness, such as meningitis or sepsis.

According to Dr Charlene Rodrigues of UKHSA, such changes can make infections more severe and allow bacteria to evade the immune system, because people have not encountered them before. She says the social setting, that is, a place of intense close contact, helped the variant spread to so many people. Meningococci spread through close contact, including kissing and sharing drinks or e-cigarettes.

Dr Rodrigues suspects that the same genetic changes may explain why the outbreak was short-lived: infected people usually became too ill to be symptom-free carriers, who pass the bacterium on without knowing. This is a supposition, not a confirmed finding.

Prof Robert Heyderman of University College London said the strain may have been carried by healthy people for some time before conditions favourable to an outbreak arose. This is also a hypothesis.

Why it matters

Events of this kind are rare and unpredictable, but according to Dr Rodrigues they could happen again, and experts should not lose sight of the threat.

As BBC reports, experts stress that the MenB vaccine, offered in England to more than a million young people starting university, protects against this variant. First doses are available until 31 December 2026, and second doses until 31 March 2027. Advisers are also asking the government to consider introducing routine MenB vaccination for teenagers aged around 15.