Britain's public health agency warned on Friday that an outbreak of measles in central England could spread to other towns and cities unless urgent action is taken to boost vaccination uptake.

The UK Health Security Agency (UKHSA) has declared a national incident, signalling a growing public health risk.

It said there had been 216 confirmed cases and 103 probable cases in the West Midlands since Oct. 1 last year, with the majority being in children aged under 10.

"With vaccine uptake in some communities so low, there is now a very real risk of seeing the virus spread in other towns and cities," UKHSA Chief Executive Jenny Harries said.

A report from the World Health Organization and the U.S. Centers for Disease Control and Prevention in November said there had been a "staggering" annual rise in measles cases and deaths globally in 2022.

Measles is one of the most contagious viruses in the world but is preventable by two doses of vaccine. The COVID-19 pandemic massively disrupted routine immunization efforts worldwide, and the bounce back has been slow.

Harries said immediate action was needed to boost uptake of the MMR (measles, mumps and rubella) vaccine in areas where it was low.

"We need a long-term concerted effort to protect individuals and to prevent large measles outbreaks," she added.

In Britain, MMR is part of the routine childhood immunisation programme offered by the state-funded National Health Service. Last year, the UKHSA said in some areas and groups in London, coverage of the first MMR dose at 2 years of age was as low as 69.5%.

In July last year the UKHSA warned of a steady rise in measles cases and the risk of a resurgence of the virus, particularly in London where it said an outbreak of 40,000 to 160,000 cases could occur due to low vaccine coverage rates.

(Reporting by Kylie MacLellan; editing by William James)