Highly contagious Mpox Clade 1b detected in the UK: Key symptoms, preventive measures to know

The United Kingdom has reported another case of the highly contagious and potentially deadly Mpox strain Clade 1b. The latest case, which was confirmed by the UK Health Security Agency (UKHSA), is the sixth known case of the virus in recent months. What is so alarming in this specific case is that the infected patient has no recent travel history to Africa and no established contact with already diagnosed Mpox patients. This has put very serious questions into whether or not the virus is spreading undetected in the UK.

Since October 2023, the UK has experienced a significant spike in Mpox Clade 1b-associated infections. Previous to this case, the overwhelming majority of reports have been related to people with recent travel histories from Africa or who had face-to-face exposure with infected individuals. This present case raises concerns because it happened to someone with no reportable exposure and its silent transmission in the population.
The UKHSA has assured the public that rapid contact tracing and risk assessments have been initiated. The health agency confirmed that the case was diagnosed in March and that all contacts have been traced, with no additional infections detected at this point. However, experts warn that undetected community transmission is still a possibility.

Mpox, previously referred to as monkeypox, is a viral illness that comes from the same family as smallpox. While it is also normally less virulent than smallpox, some strains, notably Clade 1b, are extremely virulent and lethal.
There are two main clades of the Mpox virus: Clade I and Clade II. While Clade II was the cause of the worldwide outbreaks in 2022-23 and is said to be fairly less dangerous, Clade I, including subvariant Clade 1b, is far more perilous. Research has indicated that Clade 1b has a high mortality rate and the capability to spread at a faster pace than other versions. Its appearance in a case with no exposure history makes the case especially worrying.


Several symptoms have been noted by experts as being caused by the Mpox virus, and for Clade 1b, the symptoms are more pronounced and develop quickly. The most frequent symptoms are:
- Severe muscle pains, back pain, and body aches
- Severe headache
- Severe pain in the back and sides
- Swollen lymph glands
- Chills
- Severe weakness and fatigue
- Rash that usually begins on the face and then spreads to other parts of the body
In more serious cases, Clade 1b has also been associated with complications like pneumonia, secondary infections, sepsis, and encephalitis (brain inflammation). Due to the high risk of this disease, it's important to detect it early and treat it.


After the case was detected, the UKHSA increased its surveillance. The agency has begun urgent contact tracing and risk assessments to establish how the person got infected with the virus and if there are other cases still undetected. Health officials have called on medical practitioners to be on the lookout for Mpox symptoms, particularly in patients with unexplained rashes or flu-like illnesses.
In addition, laboratories have been instructed to give high priority to testing and genetic sequencing of suspected Mpox samples to rapidly detect any other Clade 1b cases. This proactive measure is designed to contain the virus before it can further spread in the community.
Global implications and precautions
The development of Clade 1b in the UK in the absence of an identifiable source of infection implies that other areas may be at risk. The World Health Organization and other international public health agencies are monitoring the situation closely. Cases of Clade 1b have been reported in countries like the UAE, which emphasizes the need for global collaboration for tracking and regulation of the virus.
To avoid further transmission, members of the public are encouraged to exercise caution by taking the following measures:
- Practicing good hygiene and washing hands
- Not coming into close contact with persons presenting symptoms
- Seek treatment if they experience any symptoms related to Mpox
Although there have been no reported widespread outbreaks as yet, the risk of silent transmission within the community remains a serious concern. The UKHSA calls on both healthcare professionals and the general public to be vigilant. The discovery of Mpox Clade 1b in England is a major concern, given that the mode of transmission is silent. Necessary precautions to be taken to avert a possible outbreak. This variant has a high death rate and the capability to spread at a high pace, necessitating urgent action for public safety.