The UN children’s agency, Unicef, is warning that cases of measles around the world have nearly trebled compared with the same period last year.
Unicef says this has created the environment for major outbreaks of the disease, including in the Democratic Republic of Congo and Madagascar.
Measles is highly contagious and can be fatal.
According to Unicef, an estimated 160 million people around the world missed out on the measles vaccine in the period from 2010 to 2017.
And it says outbreaks of the disease are on the rise around the world. In 2017, more than 100,000 people died, most of them children.
And the problem is not just in developing countries. In the US, France, the UK and many other wealthy parts of the world, comparatively large numbers of children are unprotected.
There are many reasons for what’s happening, including poor health facilities in parts of the developing world.
In wealthier countries it’s linked to anti-vaccine messages which have been spread on social media and are untrue. But as a result some people have been choosing not to inoculate their children.