THE lethal mpox virus that has spread to Europe is mutating into new strains faster than expected, scientists say.
This makes it hard for experts to track how serious and contagious the new bugs are, complicating the response.
Mpox, formerly known as monkeypox, has been circulating in parts of Africa since 1970.
It only received global attention when the clade 2 version of the virus spread internationally to over 100 countries in 2022.
This prompted the World Health Organisation (WHO) to declare a global health emergency that ended ten months later.
A new strain of the virus, known as clade Ib, has the world’s attention again after the WHO declared a new health emergency.
It’s thought the new bug is far deadlier and more contagious than its predecessor.
The strain is a mutated version of clade I, a form of mpox spread by direct contact with infected animals that have been endemic in the Democratic Republic of Congo (DCR) for decades.
The new clade 1b virus is transmitted through close contact, such as sex, or skin-to-skin contact with another person.
Congo has had more than 18,000 suspected clade I and clade Ib mpox cases and 615 deaths this year, according to the WHO.
More recently, the clade 1b virus has been spotted in several other African countries, as well as Asia and Europe – Thailand and Sweden respectively.
“I worry that in Africa, we are working blindly,” said Dr Dimie Ogoina, an infectious diseases expert at Niger Delta University Hospital in Nigeria, told Reuters.
“We don’t understand our outbreak very well, and if we don’t understand our outbreak very well we will have difficulty addressing the problem in terms of transmission dynamics, the severity of the disease, risk factors of the disease,” he said.
“And I worry about the fact that the virus seems to be mutating and producing new strains,” he added.
The expert said it took the clade 2 virus five years to evolve into something that could spread well in humans.
The clade 1 version has done the same thing in less than a year.
Recent mpox infections contain a mutation called APOBEC3 – which tends to make viruses better at spreading in humans.
“All the human-to-human cases of mpox have this APOBEC signature of mutations, which means that it’s mutating a little bit more rapidly than we would expect,” Dr Miguel Paredes, who is studying the evolution of mpox and other viruses at Fred Hutchison Cancer Center in Seattle.
It comes as expert warn the mpox jab might fail against the new strain.
They don’t know how the jab, credited for helping put an end to the 2022 outbreak, will respond to the new version of the bug.
While no cases have yet been confirmed in the UK, experts suspect the new variant is already in Britain.
Due to how long it takes for symptoms to emerge, they believe we could see cases within the next two weeks.
However, Europe is unlikely to see as many deaths as central Africa due to better access to quality healthcare, they said.
While no cases have yet been confirmed in the UK, experts suspect the new variant is already in Britain.
Due to how long it takes for symptoms to emerge, they believe we could see cases within the next two weeks.
However, Europe is unlikely to see as many deaths as central Africa due to better access to quality healthcare, they said.
The NHS is already on high alert for UK cases of the strain.
Rapid testing is being made available and GPs and hospitals have been told to isolate those with symptoms of the mutant bug.
The Government is said to have enough vaccines and treatments to deal with an outbreak.
The NHS offers the smallpox (MVA) vaccine to people who are most likely to be exposed to mpox.
This includes healthcare workers looking after patients with suspected or confirmed mpox, men who sleep with men and people who have been in close contact with a suspected case.
You can get vaccinated before or after exposure.
Dr Jonas Albarnaz, a research fellow specialising in pox viruses at The Pirbright Institute, said:
“This news of a case of clade 1 mpox in Sweden is concerning for two main reasons.
“First, this is the first clade 1 mpox virus case outside Africa. This indicates that the extent of the international spread of clade 1 outbreak in DRC might be larger than we knew yesterday.
“And second, clade 1 mpox virus is associated with a more severe disease and higher mortality rates than the clade 2 virus responsible for the international mpox outbreak in 2022.
“This is hard to predict whether we will see further cases of clade 1 mpox outside of Africa, but this case in Sweden is a warning call for public health authorities to be vigilant and implement robust surveillance and contact-tracing strategies to detect possible new cases early on.
“It’s also critical to determine what is the link between this clade 1 mpox virus detected in Sweden and the ongoing outbreak in DRC.”
