President Trump has told Americans to “get their shots” as measles cases spread across the country.
“The vaccinations are so important,” he told reporters outside the White House.
Nearly 700 cases have been reported across 22 states amid a resurgence of the highly infectious disease, the US Centers for Disease Control and Prevention says.
Mr Trump has previously appeared to link vaccines and autism. Public health experts say there is no link.
Vaccination rates have dropped steadily in the US with many parents objecting for philosophical or religious reasons, or because they believe discredited information that vaccines cause autism in children.
There have been more than 110,000 measles cases worldwide in the first three months of 2019 – a rise of 300% compared to last year, World Health Organization figures show.
