People at higher risk of getting monkeypox will be offered second doses of the vaccine, the UK Health Security Agency said.
Sexual health clinics will continue to prioritize offering first doses to those most at risk. UKHSA said some clinics will offer eligible people a second dose, which should provide longer-term protection.
The model published on Friday suggests that vaccinating the 25% of groups most at risk could significantly reduce the risk of transmission.
It comes as infection cases continue to drop. At the beginning of September there were less than 15 cases per day on average.
Dr Gayatri Amirthalingam, deputy director of public health programmes, UKHSA, said: “It is encouraging that we continue to see fewer cases of monkeypox reported in the UK and we are grateful to all who have followed advice about possible symptoms, isolated as part of this outbreak or introduce a vaccine to help limit transmission.
“Prioritizing vaccine stock where possible for second doses for people most at risk will help us maximize protection and interrupt transmission. When they call you to be vaccinated, accept the offer.”
Symptoms of infection include high fever, headache, muscle aches, and swollen glands.
The Joint Committee on Vaccination and Immunization backed the UKHSA proposal to offer second doses to people most at risk. There are no current plans to expand vaccination offerings beyond existing priority cohorts, but the decision will remain under review.
The NHS will contact those who are eligible for vaccination. The second doses will be offered about two to three months after the first dose.
As of September 20, more than 45,000 people have received a dose of the vaccine, including more than 40,000 gay, bisexual, and other men who have sex with men who are at the highest risk of exposure. As of September 16, there were 3,585 confirmed and highly probable cases of monkeypox in the UK.