Cases of the new MPOX variant, which kills one in 10 people who become infected, may have now spread to three countries outside Africa.
Sweden is the first country outside the continent to confirm a case of the new mpox strain, called clade 1b, which has been sweeping through Central Africa and has claimed hundreds of lives since the outbreak began.
Pakistan and the Philippines have now reported suspected cases, but are still awaiting test results to confirm whether the mpox case is specifically linked to the strain that raised alarm bells.
Experts suspect that the new variant is already present in Great Britain.
Infectious disease specialists told MailOnline that it could take up to 17 days for symptoms to appear, meaning the first case in the UK could be confirmed within days or weeks.
This long incubation period also means that border officials are unlikely to detect such cases, making airport screening unlikely to be effective, the researchers said.
Adding to the confusion, another species of mpox, previously called monkeypox, has re-emerged in the UK.
Latest official data shows that in July this year, twice as many fewer fatal cases of clade 2 mpox were recorded than in the previous month.
The total of more than 40 cases in July is the highest number in more than a year.
And as the maps on this website show, cases of the clade 2 variant, which is much less deadly than the globally concerning clade 1, are also being recorded around the world.
The World Health Organization (WHO) last week declared the ongoing MPOX outbreak in several Central African countries a “public health emergency of international concern”.
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In the 2022 outbreak, thousands of cases were recorded in the UK, mainly in London
This is the same name the WHO gave to Covid in late January 2020, just weeks before the virus spread across the world. Some scientists have compared the current outbreak to the “early days of HIV.”
A few days ago, the first case of the new mpox variant outside the continent was detected in Sweden. The European Centre for Disease Prevention and Control has therefore raised the risk level.
Suspected cases of the new variant have also been identified in two patients, in Pakistan and the Philippines.
However, health authorities there have said that MPOX testing is still ongoing to determine whether these patients have actually been infected with the new variant.
Mpox, formerly known as monkeypox, is a rare viral infection that people usually contract in the tropical regions of West and Central Africa. Shown is a colored transmission electron micrograph of monkeypox particles (green) found inside an infected cell (pink and purple)
According to the UK’s Health Security Agency, no cases have yet been identified in the UK and the risk to the public remains ‘low’.
However, rapid tests are being made available and GPs and hospitals have been instructed to isolate people with possible symptoms.
The government is said to have sufficient vaccines and treatments to deal with a possible outbreak.
Professor Paul Hunter, an infectious diseases expert at the University of East Anglia, told MailOnline the new variant of mpox was likely already present in the UK.
“Given that it can take up to 17 days for symptoms to appear and then another week for the diagnosis to be confirmed, it is certainly likely, but not certain, that we already have this clade here,” he said.
He added that, as with the clade 2 variant, sexual contact remains the primary route by which the new variant spreads and that groups such as men who have sex with men are therefore at greater risk.
“1b was first found in sex workers and is spread primarily through sexual contact,” he said.
“So I think this new clade will spread most effectively within the same population.”
An outbreak of mpox clade 2 spread through Europe in 2022 and occurred mainly through sexual contact, especially among gay and bisexual men.
This led to these groups being offered an mpox vaccine by the NHS, alongside other at-risk groups, such as people working in sex venues and NHS staff treating potential patients.
Nearly 100,000 people were infected in 2022 during that global outbreak of the disease.
In the United States, a staggering 32,063 cases were reported during that period, with 58 deaths. Significant numbers of cases were reported in North, Central and South America, Europe, Africa, Asia and Australasia.
However, the outbreak is estimated to have killed only 183 people, while this strain has an estimated death rate of about one in every 500 people infected.
By comparison, the new 1b strain is estimated to kill one in 20 adults and one in 10 children.
However, experts say it is unlikely that these death rates, which occur in Central Africa, will be the same in developed countries due to greater access to higher quality health care.
However, there are still cases of the 2022 mpox variant known. Since the beginning of the year, more than 5,000 cases have been registered worldwide.