LONDON, United Kingdom - The UK Health Security Agency on Tuesday recommended that some gay and bisexual men at higher risk of contracting monkeypox should be offered a vaccine to control an outbreak.
A total of 793 cases of the chickenpox-like disease have been recorded across the country as of Monday, the public health body said.
Head of immunisation Mary Ramsay said contact tracing had helped to limit the spread "but we are continuing to see a notable proportion of cases in gay, bisexual and other men who have sex with men".
"By expanding the vaccine offer to those at higher risk, we hope to break chains of transmission and help contain the outbreak," she added in a statement.
The virus is not currently classified as a sexually transmitted infection but can be passed on by intimate close contact.
The UKHSA recommends men considered to be at higher risk of exposure should be given the smallpox vaccine Imvanex.
The strategy has been backed by government scientific advisory body the Joint Committee on Vaccination and Immunisation, it added.
Vaccination could be recommended for men who have multiple partners, those who participate in group sex or attend "sex on premises" venues.
Monkeypox, whose symptoms include a high fever, swollen lymph nodes and a blistery chickenpox-like rash, has until the past few months been confined to western and central Africa.
But between January 1 and June 15 there have been more than 2,100 confirmed cases in 42 countries, according to the World Health Organization.
The WHO is due to hold an emergency meeting on Thursday to decide whether to classify the outbreak as a public health emergency of international concern -- the highest level the UN agency can give.