Measles surged to infect almost 870,000 people across the world in 2019, the worst figures in almost a quarter of a century as vaccination levels fell below critical levels, a report said on Thursday. Millions of children are at risk of the disease again this year as restrictions imposed to contain the COVID-19 pandemic further disrupt immunisation programmes, the report co-led by the World Health Organization (WHO) said. Measles is one of the most contagious known diseases - more so than COVID-19, Ebola, tuberculosis or flu.