Two new cases of the mpox variant clade 1b detected in the United Kingdom are the first locally transmitted cases in Europe and the first outside Africa, the World Health Organization announced Tuesday.
The UK Health Security Agency (UKHSA) confirmed on Monday evening that the two new cases were household contacts of the first UK case identified last week, bringing the total number of confirmed cases in the country to three.
The WHO has warned that European states should prepare for “rapid action” to contain the latest mpox variant, which is spread through close physical contact, including sex and sharing enclosed spaces.
These two cases are also the first to be locally transmitted outside Africa since August 2024, when the WHO declared the outbreak of the new variant an international public health emergency – its highest level of alarm.
Affected people are receiving specialist care and the risk to the UK population “remains low”, the UKHSA said.
The initial case was detected after the person traveled to several African countries on holiday and returned to the UK on October 21.
The patient developed flu-like symptoms more than 24 hours later and, on October 24, began developing a rash that worsened in the following days.
Viral smallpox, a viral disease related to smallpox, has two types, clade 1 and clade 2. Symptoms include fever, rash or pus-filled blisters, swollen lymph nodes, and body aches.
The WHO first declared an international public health emergency in 2022 following the spread of clade 2. This outbreak primarily affected gay and bisexual men in Europe and the United States.
Vaccination and awareness campaigns in many countries have helped stem the number of cases worldwide and the WHO lifted the emergency in May 2023 after reporting 140 deaths out of around 87,400 cases.
In 2024, a double epidemic of clade 1 and clade 1b, a new strain that affects children, has spread widely in the Democratic Republic of Congo.
The new strain has also been recorded in neighboring Burundi, Kenya, Rwanda and Uganda, with imported cases in Sweden, India, Thailand, Germany and the United Kingdom.
