Four more cases of monkeypox have been identified in England, UK Health Security Agency (UKHSA) said on Monday.
It brings the total number of confirmed cases of the disease to seven.
The UKHSA issued an alert after all four latest patients “self-identify as gay, bisexual, or other men who have sex with men (MSM),” advising these groups to watch for unusual rashes or lesions.
Monkeypox, a disease caused by the monkeypox virus, is endemic in some African countries. “Relatively limited” human-to-human transmission of the disease can result from “close contact with respiratory secretions, skin lesions of an infected person or recently contaminated objects” or “prolonged face-to-face contact” with a patient, according to the World Health Organisation.
Most patients recover within a few weeks, but severe illness can occur in some people, the UKHSA said.
The first case in England was detected on May 6, with the patient having a recent travel history from Nigeria. The patient was treated at the expert infectious disease unit at the Guy’s and St Thomas’ NHS Foundation Trust in London.
But the causes of the other infections remain under investigation.
The second and third cases, which the UKHSA confirmed on Saturday, live together in the same household in London, but do not have known links to the first case. One of them was treated at St Mary’s Hospital, Imperial College Healthcare NHS Trust, London, and the other one was isolated and didn’t need hospital treatment.
Among the latest four cases, three of them were identified in London, and the fourth was found in the northeast of England. They have no known links to the three previously confirmed cases or to travel to a country where monkeypox is endemic.
The UKHSA said they all appeared to have been infected in London.
The case in northeast England is linked to one of the London cases, and investigations are underway to establish further links.
The UKHSA didn’t specify how many needed hospital treatment, but said those who did were at the Royal Free Hospital, Royal Victoria Infirmary in Newcastle upon Tyne, and Guys’ and St Thomas’ in London.
The agency added that the individuals have the West African clade of the virus, which is mild compared to the Central African clade.
The UKHSA said it will contact people who might have been in close contact with the patients to provide information and advice as a precautionary measure.
Dr. Susan Hopkins, chief medical adviser at the UKHSA, said: “This is rare and unusual. UKHSA is rapidly investigating the source of these infections because the evidence suggests that there may be transmission of the monkeypox virus in the community, spread by close contact.
“We are particularly urging men who are gay and bisexual to be aware of any unusual rashes or lesions and to contact a sexual health service without delay.
“We are contacting any potential close contacts of the cases to provide health information and advice.”
