Approximately 21 million children worldwide are not having measles vaccinations every year, substantially increasing their risk of raising the risk of the disease later in life.

These new figures released by UNICEF show that the issue is particularly problematic in high income countries, with the US, France and the UK with the highest numbers of unvaccinated children amongst developed countries between 2010 and 2017.

In the first three months of this year, more than 110,000 measles cases were reported worldwide. This represents a threefold rise from the same period last year. An estimated 110,000 people, most of them children, died from measles in 2017, a 22% increase from the previous year. Two doses of the measles vaccine are needed to protect children. However, UNICEF’s figures show that there is a considerable drop off in children receiving the second dose.

The rising numbers of unvaccinated children has been attributed to the rise of the ‘anti-vax’ movement, which spreads myths about vaccine safety. One of the most notorious figures in the movement is Andrew Wakefield, a former British doctor who first raised doubts about the combined measles mumps and rubella (MMR) vaccine in the late 1990s. His research was subsequently found to be fraudulent but his work has remained highly influential.

The issue is also problematic in low and middle-income countries. In 2017, Nigeria had the highest number of children under one year of age who missed out on the first dose, at nearly four million. It was followed by India (2.9 million), Pakistan and Indonesia (1.2 million each), and Ethiopia (1.1 million).

“The ground for the global measles outbreaks we are witnessing today was laid years ago,” said Henrietta Fore, executive director of UNICEF. “The measles virus will always find unvaccinated children. If we are serious about averting the spread of this dangerous but preventable disease, we need to vaccinate every child, in rich and poor countries alike.”