Public health officials are set to announce more cases of monkeypox in the United Kingdom on Monday, as efforts intensify to contain the first multinational outbreak of the virus that has resulted in cases in at least 14 countries.
The unusual outbreak of the rare disease has sparked a flurry of contact tracing and testing with the closest contacts of confirmed cases – such as partners and people in the same household – offered a vaccine and asked to isolate at home for up to 21 days.
Under UK Health Security Agency guidance, high-risk people are advised to avoid immunosuppressed people, pregnant women and children under 12 years of age, as they are at higher risk of serious infections.
While some monkeypox patients have been hospitalized, many confirmed cases who do not need specialized care have been asked to isolate at home until local health protection teams are confident they are no longer contagious. “The vast majority of cases identified are isolated at home and do not require hospitalization,” said Dr Claire Deusnap, chair of the British Association for Sexual Health and HIV.
Monkeypox does not spread easily, and most people infected will only have mild symptoms, including fever, rash, and blisters, which can go away without treatment. But the virus can cause more serious illnesses in those with weakened immune systems, pregnant women, and young children.
Dr Susan Hopkins, chief medical advisor for the UK’s Health Security Agency, said other cases identified over the weekend would be confirmed on Monday. Since the UK’s first case was announced on May 7 – a person who arrived in London from Nigeria – the agency has confirmed 19 more cases, mostly among young men who have sex with men.
The outbreak is unusual because although there have been sporadic cases of monkeypox in the UK before – seven cases from 2018 to 2021 – all previous cases were linked to travel from Nigeria. Most of the recent cases in the UK and abroad have no known links to parts of West or Central Africa where the virus is endemic.
Globally, more than 180 confirmed or suspected cases are being investigated in at least 14 countries. More than half of them are in Spain and Portugal. Genetic analysis of three monkeypox viruses from the outbreak found that it closely matches the virus that spread from Nigeria in 2018 and 2019. The same studies suggest that a Belgian man contracted the virus on a recent trip to Portugal.
The outbreak pattern indicates that the virus is mainly spread through sexual networks. The infection can be transmitted through close contact with body fluids, infected ulcers, and contaminated items such as towels and bedding. Ultra-widespread events may have fueled the outbreak since its arrival in Europe.
“I think it’s likely that some of these outbreaks are driven by super-spreading events,” said Dr Michael Head, a senior researcher in global health at the University of Southampton. “For example, Spanish health authorities view the sauna as a single exposure site that has led to many secondary cases. The mild presentations of many cases may also be a factor, as people will be more mobile and likely to socialize. However, we still Need to understand more about transmission dynamics.”
Hopkins told BBC One Morning that community transmission in the UK was “largely concentrated in urban areas and we see it mostly in individuals who identify as gay, bisexual, or other MSM”. When asked why most cases were in that group, she said, “This is because of the frequent close contacts they may have had.
“We are discovering more cases on a daily basis and I would like to thank all those people who come forward for testing in the sexual health clinics, GPs and emergency department. We have found cases that have no specific contact with a West African individual, which we have seen previously in this country.
“We recommend anyone who regularly makes changes in sex partners, or is in close contact with individuals they don’t know, to come forward if they develop a rash.”
Dewsnap said sexual health clinics have already been under tremendous pressure due to cutbacks and lack of support in recent years, while there has been a “worrying number of urogenital specialist positions vacant in sexual health clinics.”