Britain Confirms Two Cases of Clade Ib Type of Mpox

Officials stated that the likelihood of a swift outbreak is still minimal since the new cases were linked to someone in the same household as the initial infected individual.

November 5, 2024, at 11:53 a.m. Eastern Time

According to health officials in the UK, two additional instances of the mpox strain responsible for a severe outbreak in central Africa have been identified. However, they emphasize that the likelihood of a swift transmission throughout the country remains low.

According to a statement from the United Kingdom Health Security Agency on Monday, both individuals had recently been in contact with a person in Britain who tested positive for the virus last week. An mpox vaccine is now being offered to all three infected individuals, who are currently receiving treatment in hospitals in London.

"Mpox spreads easily in homes where people are in close contact, so it's not surprising that we are seeing more cases in the same household," said Susan Hopkins, the chief medical adviser for the agency, in her statement.

The illness, previously referred to as monkeypox, has been a common health issue in West and Central Africa for over five decades. However, in 2022, there was a larger outbreak that led to the disease spreading to Europe, the United States, and various other regions around the globe.

The outbreak started to decline last year, and the number of mpox cases reported in Britain and other parts of Europe has been low since then. However, the strain of mpox identified in the three new cases poses a more serious risk.

According to the World Health Organization, a specific variant called Clade Ia has resulted in over 30,000 infections and at least 990 deaths in the Democratic Republic of Congo since the beginning of the year. UNICEF, the United Nations children's agency, reports that more than half of the new mpox cases in Congo are affecting children.

The variant found in patients in the UK, called Clade Ib, is seen as a greater risk because it seems to spread more easily between people, including through close contact at home and through sexual activity. In contrast, Clade Ia is primarily contracted through coming into contact with infected animals or by consuming contaminated meat.

The initial sign of the illness, which has a strong connection to smallpox, commonly manifests as a rash that can progress to form blisters, as stated by the World Health Organization. Patients often report additional symptoms such as muscle aches, fever, and headaches.

In August, Sweden reported the first European instance of the more dangerous strain of mpox. Then, in September, Germany identified a case in an individual who had visited an affected region in Africa, according to the European Center for Disease Prevention and Control. As of last week, the center noted that neither country has reported any additional cases of Clade I mpox since these occurrences.

According to the Health Security Agency, the individual diagnosed with mpox in Britain last week had traveled to countries in Africa where the disease is present.

As of this year, Europe has reported over 28,000 cases of mpox, based on information from the E.C.D.C. and the W.H.O. The majority of these cases are linked to the strain of mpox that caused the outbreak in 2022.

The version called Clade IIb mainly transmitted through sexual interactions, with men who have sex with men being the group most vulnerable to infection. The spread of the outbreak decreased thanks to the availability of vaccines and changes in people's behaviors.

According to Michael Marks, a professor of medicine at the London School of Hygiene & Tropical Medicine, most individuals who get mpox usually experience a mild illness that resolves on its own. They can expect to make a full recovery, especially if they have access to specialized medical care and vaccinations.

"Even though Clade I mpox viruses seem to lead to somewhat more severe illnesses, in general, most people tend to have positive outcomes," he stated.

Lynsey Chutel is a journalist for The Times, located in London, who reports on urgent news stories from Africa, the Middle East, and Europe. Learn more about Lynsey Chutel.