U.K. Reports First Cluster Outside of Africa of New Mpox Variant

THURSDAY, Nov. 7, 2024 (HealthDay News) -- Four cases of the more infectious variant of mpox have been reported in the U.K., making it the first cluster of infections that have surfaced outside of Africa.

British authorities announced the first case in that country last week, saying the person was being treated at a London hospital after recently traveling to countries in Africa where there are ongoing outbreaks.

"This is the first time we have detected this clade of mpox in the U.K., though other cases have been confirmed abroad," Susan Hopkins, chief medical adviser at the UK Health Security Agency, said in a health alert issued at the time. "The risk to the UK population remains low, and we are working rapidly to trace close contacts and reduce the risk of any potential spread."

This week, the agency issued an update saying it has identified three more cases in people who lived in the same home as the first patient. They are now being treated at a hospital in London.

“Mpox is very infectious in households with close contact, and so it is not unexpected to see further cases within the same household,” Hopkins noted in the updated alert.

Still, health officials at the National Health Service (NHS) said that they are ready to do more if needed.

"While the risk of catching mpox in the UK remains low, if required the NHS has plans in place to expand the rollout of vaccines quickly in line with supply," Steve Russell, NHS national director for vaccination and screening, noted in the health alert.

This new variant of mpox was first detected earlier this year in eastern Congo. It has also caused outbreaks in Burundi, Kenya, Rwanda and Uganda, while single cases in travelers have been reported in Sweden, India, Germany and Thailand, the Associated Press reported.

To date, there have been about 43,000 suspected cases of mpox in Africa, including more than 1,000 deaths, mostly in Congo, the AP said.

In response to the ongoing outbreak, the World Health Organization announced on Wednesday that it had allocated 899,900 vaccine doses to the nine African countries that are struggling mightily with the spread of mpox.

"In recent weeks, limited vaccination has begun in the Democratic Republic of the Congo and Rwanda," the WHO said in its announcement. "This allocation to the 9 countries marks a significant step towards a coordinated and targeted deployment of vaccines to stop the mpox outbreaks."

In an early sign that the outbreak in Africa might be ebbing, some health officials reported earlier this week that case counts seem to be stabilizing in the Congo, the epicenter of the outbreak.

The World Health Organization first declared the mpox outbreak a global health emergency in August, but recent WHO data has shown the Congo has reported about 200 to 300 lab-confirmed mpox cases every week, down from nearly 400 cases a week in July, the AP reported.

Still, the WHO acknowledged that only 40% to 50% of suspected infections in Congo were being tested and the virus continues to spread elsewhere on the continent, the AP reported.

While doctors are encouraged by the drop in infections in some parts of Congo, they are worried by the small number of vaccine doses the central African nation has received so far to fight the outbreak, the AP reported. WHO has estimated that only 50,000 people have been immunized in Congo, which has a population of 110 million.

“If we miss this opportunity, the likelihood of another significant outbreak increases substantially,” Dr. Zakary Rhissa, who heads operations in Congo for the charity Alima, told the AP.

The Africa Centers for Disease Control and Prevention has estimated Congo needs at least 3 million mpox vaccines to stop the virus, and another 7 million are needed for the rest of the continent.

“We’ve seen how past outbreaks, such as the one in Nigeria in 2017, can lead to larger global events if not effectively contained,” Rhissa noted. That 2017 Nigerian outbreak triggered the 2022 global outbreak of mpox that affected more than 100 countries.

In this latest outbreak, less than half of the people who are most at risk in the Congo have been vaccinated, Heather Kerr, Congo director for the International Rescue Committee, told the AP.

“We only have a tiny amount of vaccines, and nothing for the kids,” she said.

What's most worrying about the new outbreak is that the death rate linked to the new strain of the disease appears higher: About 3 percent of those infected have died, instead of the 0.2 percent observed in the 2022 outbreak.

In 2023, scientists discovered that the mpox virus has gained mutations allowing it to spread more easily between people. Sexual transmission, often through heterosexual prostitution, is a main conduit for infection in Africa.

Dr. Nicole Lurie is executive director for preparedness and response at the Coalition for Epidemic Preparedness Innovations, a nonprofit that finances vaccine development.

Speaking to the New York Times recently, she said, “this outbreak has been smoldering for quite a long time, and we continually have missed opportunities to shut it down. I’m really glad that everybody is now paying attention and focusing their efforts on this.”

More information

Find out more about mpox at the U.S. Centers for Disease Control and Prevention.

SOURCE: UK Health Security Agency, health alert, Nov. 6, 2024; Associated Press; WHO, news releases, Nov. 6, 2024 and Aug. 26, 2024; New York Times