Young people who are hitting nightclubs and beaches are leading a rise in fresh coronavirus cases across the world, with the proportion of those aged 15 to 24 who are infected rising three-fold in about five months, the World Health Organization said. An analysis by the WHO of 6 million infections between Feb. 24 and July 12 found that the share of people aged 15-24 years rose to 15% from 4.5%. Among those aged 5-14 years, about 4.6% were infected, up from 0.8%, between Feb. 24 and July 12, the WHO said, at a time when testing has risen and public health experts are concerned that reopening of schools may lead to a surge in cases.