First UK case of new clade 1b mpox variant detected in London

The UK Health Security Agency (UKHSA) announced on October 30, 2024, that it has detected the first case of infection with a new variant of the mpox virus, Clade 1b, in London. The individual had recently traveled to African countries experiencing community cases of Clade 1b mpox.

The patient flew back to the UK on an overnight flight on October 21 and began to feel unwell more than 24 hours after arriving home. Flu-like symptoms developed on October 22, followed by a rash on October 24, which worsened over the following days. The rash started as raised spots that turned into sores or fluid-filled blisters, eventually scabbing and falling off. On October 27, the person attended an emergency department in London, where they were swabbed for the virus and sent home to isolate while awaiting results. Laboratory testing confirmed the infection was Clade 1b mpox.

The patient is currently being treated at a high-dependency infectious diseases unit at the Royal Free Hospital in London. Authorities are tracing fewer than 10 household contacts the individual may have had contact with. The UK Health Security Agency explained, "All contacts of this person will be offered a test and a vaccine if necessary and will be informed about additional care that should be provided if they present symptoms or if the test is positive."

Professor Susan Hopkins, the UKHSA's chief medical adviser, stated: "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. In accordance with established protocols, investigations are underway to learn how the individual acquired the infection and to assess whether there are any further associated cases."

Health and Social Care Secretary Wes Streeting said: "We are working with UKHSA and the NHS to protect the public and prevent transmission. The overall risk to the UK population currently remains low."

Clade 1b mpox is thought to be more dangerous than Clade II, appearing to spread more easily between people and causing more severe disease. This variant has been widely circulating in the Democratic Republic of the Congo (DRC) and has spread to neighboring countries, including Burundi, Rwanda, Uganda, and Kenya. Cases have also been detected in Germany, Sweden, India, and several Asian countries, with some linked to travel to affected regions.

Mpox, formerly known as monkeypox, is a viral infection related to smallpox that typically causes flu-like symptoms, including fever, muscle pain, and skin lesions. The illness can last two to four weeks. Symptoms include high temperature, headache, muscle aches, backache, swollen glands, exhaustion, joint pain, and a characteristic lumpy rash with pus-filled lesions. A rash usually appears one to five days after flu-like symptoms begin.

The virus spreads through close physical contact, including sexual contact, kissing, cuddling, holding hands, and direct contact with a rash or bodily fluids. It can also be transmitted through coughs and sneezes at close proximity. Mpox has been linked to dangerous complications for pregnant women, including miscarriage.

The UKHSA noted that this is the first detection of this type of mpox in the United Kingdom. "It is different from mpox Clade 2, which has been circulating at low levels in the United Kingdom since 2022, mainly among homosexuals and bisexuals," the agency stated. Clade II mpox sparked the 2022 global outbreak of the disease, primarily affecting gay, bisexual, and other men who have sex with men in Europe and the United States.

The UKHSA is collaborating with the NHS and academic partners to determine the characteristics of the Clade 1b virus and further assess the risk to human health. The agency is treating Clade 1b as a high consequence infectious disease (HCID) and will adapt its response as more data emerges. Extensive planning has been underway to ensure healthcare professionals are equipped and prepared to respond to any confirmed cases of mpox Clade 1b.

Vaccination and awareness drives in many countries, including the UK, have helped stem the number of worldwide mpox cases. The UKHSA stated the country has an existing stock of mpox vaccines. Last month, the agency announced that further vaccines are being procured to support a routine immunisation programme, with over 150,000 doses ordered to boost preparedness. The decision to procure further vaccines is in line with more recent independent Joint Committee on Vaccination and Immunisation (JCVI) advice.

Globally, the World Health Organization (WHO) declared outbreaks in Africa a global health emergency in July 2022 due to the rapid spread of mpox, particularly after an outbreak in the DRC spread to neighboring countries. The WHO lifted the emergency declaration in May 2023 after reporting 140 deaths out of roughly 87,400 cases.

Clade 1b mpox has also been reported in Germany, with a case detected on October 22, 2024. Additional cases have appeared in Sweden and several Asian countries. Clade 1b cases have been recorded in countries that had not previously detected mpox, highlighting the variant's potential for wider spread.

Mpox has two main subtypes: Clade I and Clade II. Clade 1b, a subtype of Clade I, appears to be more dangerous as it spreads more easily between people and can cause more severe disease. Clade I mainly affects children, while Clade II has been present in the UK since 2022, with infections still happening at low levels.

Anna Popova, head of Rospotrebnadzor, commented on the global situation: "We decided that we had already survived all the terrible things in the era of COVID. Unfortunately, this is not the case."

The UKHSA emphasized the importance of vigilance and public health measures to prevent the spread of the virus. Close contacts of the individual will be offered mpox tests, vaccination, and healthcare advice if they are found to have the virus.

In recent months, a new outbreak of mpox has been affecting Africa, with the highest infection rates reported in the DRC, Burundi, and Nigeria. As of early September 2024, over 600 deaths from the mpox virus had been reported.

Vaccination and awareness campaigns have been crucial in reducing the number of cases worldwide. The UKHSA, NHS, and partner organizations have well-tested capabilities to detect, contain, and treat novel infectious diseases, contributing to the low risk of catching mpox in the UK.

Sources: Liverpool Echo, expressandstar.com, LaRepublica.pe, Izvestia.ru, Back to homepage, Yahoo News, France 24, www.elcolombiano.com, Nilepost News, Home, AL24 News

This article was written in collaboration with generative AI company Alchemiq