A new deadlier variant of mpox, previously known as monkeypox, is “very likely” to already be in the UK, an infectious diseases expert has told Sky News.
The clade 1b strain has been confirmed in Sweden and Pakistan after first being detected in the Democratic Republic of the Congo (DRC) and is believed to be the most dangerous so far.
The World Health Organization declared it a global health emergency this week due to it spreading to 13 African countries – where more than 15,600 cases and 537 deaths have been reported.
Professor Paul Hunter said it was “very likely” someone in the UK already has the new variant of the viral disease.
However, he said it probably wouldn’t be confirmed for a few weeks until people with symptoms visit a doctor and their samples are tested.
“When someone gets an infection it typically takes several days before they develop the classic appearance that would make people think ‘oh, this is mpox‘,” Prof Hunter told Sky News.
“Then it can take longer before the samples are taken and sent to the lab, it’s identified as mpox and sent for sequencing so we know which clade of mpox it is.”
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The disease causes blisters on the face and elsewhere and mainly spreads when fluid from these lesions is passed on during sexual contact.
It normally begins with fairly non-specific symptoms that could be mistaken for flu or COVID, before blisters start to emerge, said Prof Hunter.
Despite being the second time in three years mpox has been declared an emergency, he said for most people it’s a “relatively mild” illness they recover from of their own accord.
Prof Hunter said the risk of infection is also very low unless people are involved in certain “sexual networks” involving multiple partners – with the DRC strain first spotted among sex workers.
Infection via methods such as reusing towels and other skin-to-skin contact is possible but rare, he added.
The UK Health Security Agency (UKHSA) has also said the risk “is currently considered low” – while the existing mpox vaccine is said to be effective against the new strain.
Read more:
How does mpox spread and what is the risk to rest of the world?
A less severe mpox variant, clade 2, prompted a WHO health warning in 2022 and is still present in the UK – with about 180 cases detected this year, added Prof Hunter.
He told Sky News: “Although the mortality rate [for the new variant] in Africa is quite high – 3-4 % – it’s likely to be much lower if it does spread throughout Europe.”
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“One of the ways you reduce the mortality rate is by providing really good supportive care – as long as you can keep people alive until they can better of their own accord… that’s really effective at reducing mortality.”
Anyone with a potential infection is advised to go their genito-urinary clinic or see a GP.
