Mpox ( formerly monkeypox) infections have increased in the capital over the last 4 weeks, said the UK Health Security Agency (UKHSA), as it urged those at risk to come forward for mpox vaccination ahead of the summer season.
The latest increase in mpox cases was a reminder that "the infection has not gone away", said the UKHSA, which cautioned that people should "remain vigilant to mpox ahead of the summer months". As mpox is caused by a virus to similar to the smallpox virus, the historic modified vaccinia Ankara (MVA) smallpox vaccine is being offered by the NHS to people who are most likely to be exposed to mpox.
Majority of New Cases in Unvaccinated or Partially Vaccinated Individuals
Highest risk groups include gay, bisexual or other men who have sex with men who have multiple sexual partners, participate in group sex or attend sex on premises venues. Transmission is occurring primarily within interconnected sexual networks, mainly concentrated in London. Involved individuals are eligible to receive two NHS-funded vaccine doses, as are healthcare staff who work in relevant premises.
In an interim epidemiological update, the UKHSA reported a further 10 cases of mpox diagnosed in the UK between 30 April and 25 May 2023, since its last epidemiological update on 4 May. The new cases bring the total diagnosed in the UK since the beginning of the year to 20.
The UKHSA noted that mpox is a zoonotic infection due to infection with the monkeypox virus that occurs mostly in West and Central Africa. Prior to 2022, cases diagnosed in the UK had been either imported from countries where mpox is endemic, or from contacts with documented epidemiological links to imported cases.
Earlier this month the World Health Organisation declared that monkeypox was no longer a global emergency.
All the new cases were diagnosed in London, though four people were thought to have acquired the infection abroad. Five cases were acquired in the UK, with one remaining under investigation. Five of the new cases occurred in unvaccinated individuals, and two in people who had received only one vaccine dose.
At Risk Individuals Should 'Remain Alert'
Katy Sinka, UKHSA's head of sexually transmitted infections, said: "It is clear from these latest statistics that mpox has not gone away. While mpox infection is mild for many, it can cause severe symptoms for some, so it’s important people remain alert to the risks. Vaccination is key to reducing the severity of symptoms and preventing further transmission. Uptake of first doses has been strong but only around a third of those who have received their first dose have had their second dose so far."
She warned: "The programme is coming to an end, so we strongly encourage everyone eligible to please come forward for a vaccination if you haven't yet had one or two doses. Our aim is to eliminate this unpleasant disease from the UK entirely – vaccination and community action have worked very well to significantly reduce case numbers and we can’t let our guard down now."
According to the UKHSA, its data showed that one dose offers 78% protection from 14 days after receipt, while the second dose aims to provide longer term protection.
Under the current programme, at risk individuals can still book a first dose by 16 June 2023 and their second dose by the end of July 2023.
A spokesperson for the UKHSA said: "The Government remains committed to sustaining reduced transmission of mpox and achieving the ultimate goal of eliminating transmission of the disease in the UK."