Britain’s Health Security Agency said on Friday that measles vaccination rates in parts of London have dropped so low that the capital could see tens of thousands of cases of the rash-causing disease unless immunization coverage is quickly boosted.
In a statement, the agency said that among some groups of children in London, fewer than 70% have received their first dose of the standard measles, mumps and rubella vaccine; two doses are needed to provide protection. Measles is among the world’s most infectious diseases and health experts estimate that about 95% of the population must be immunized to stop new outbreaks.
The Health Security Agency said that although the risk of an outbreak across the U.K. was low, the current levels of immunization in London suggest that “a measles outbreak of between 40,000 and 160,000 cases could occur in the capital.” As of June 30, there have been 128 cases of measles in Britain this year, versus 54 cases last year. More than 60% of the cases in 2023 have been in London.
Britain's National Health Service said it was starting a targeted national campaign to boost measles vaccination in communities with the lowest coverage rates.
U.K. officials said people aged 19 to 25 were at particularly high risk of catching measles, noting that many of them may have missed vaccinations following spurious allegations made by British physician Andrew Wakefield in 1998 that the MMR vaccine was linked to autism. The research was later discredited and Wakefield was barred by medical authorities for misconduct, but he seeded an anti-vaccination movement that damaged immunization rates in the U.K. and beyond for years.
Globally, measles immunization rates have dropped substantially in the wake of the coronavirus pandemic; the World Health Organization warned last November that about 40 million children in the world missed a measles vaccine dose in 2021. In Europe, the WHO noted that cases have jumped in some countries including Russia, Austria, Serbia and the U.K. this year.
Measles is an airborne disease and typically causes a cough, red eyes and a facial rash. Serious complications are mostly seen in children under five and adults over 30 and include blindness, encephalitis and pneumonia.
In 2021, the disease killed more than 128,000 people, mostly children under five, according to the WHO.