The new coronavirus is quickly destroyed by sunlight, according to new research announced by a senior US official on Thursday, though the study has not yet been made public and awaits external evaluation.

William Bryan, science and technology advisor to the Department of Homeland Security secretary, told reporters at the White House that government scientists had found ultraviolet rays had a potent impact on the pathogen, offering hope that its spread may ease over the summer.

“Our most striking observation to date is the powerful effect that solar light appears to have on killing the virus, both surfaces and in the air,” he said.