Brits have been warned to get vaccinated against mpox as a mutant strain of the viral disease spreads through Europe. At least 46 cases of mpox clade 1b, a strain that emerged in the Democratic Republic of Congo in late 2023, have been confirmed across Europe since August, according to reports. The strain, which is thought to be more infectious than other versions of the disease formerly known as monkeypox, has infected people no travel history, unlike previous cases which were directly linked to Africa.

The UK Health Security Agency (UKHSA) said cases in the USA, Spain, Italy, the Netherlands and Portugal suggest there is now community transmission of the rare virus on a global scale. As of October 20, 16 clade 1b mxpox cases had been reported in England, according to the UKHSA, with the majority of US and Europe-based transmissions linked to gay and bisexual men, a trend that had not previously been observed in the strain.

Ioannis Karagiannis, a consultant for the World Health Organisation (WHO), said recent cases of transmission between people with no known contact with infected individuals or travel history marked a major shift in the nature of the outbreak.

“The situation has changed drastically in Europe since the end of August,” he told The Telegraph. “We now have local transmission among people with no travel history and, most notably, within men who have sex with men.”

As well as spreading more easily, the clade 1b strain is thought to be more dangerous than other variants.

Symptoms of infection include fever, aches, a skin rash, pus-filled lesions and, in severe cases, death. The strain can also cause complications in pregnant women including miscarriage.

The mxpox vaccine is available on the NHS to gay and bisexual men, healthcare workers in high-risk environments including sexual health clinics and people who have been in close contact with those confirmed to be infected.

Dr Katy Sinka, head of sexually transmitted infections at UKHSA, said: “The ways in which we are seeing mpox continue to spread globally is a reminder to come forward for the vaccine, if you are eligible.

“Although mpox infection is mild for many, it can be severe. Getting vaccinated is a proven effective way to protect yourself against severe disease, so please make sure to get the jab if you are eligible.”