US President Donald Trump said Monday he expected the coronavirus outbreak that has killed more than 900 people to disappear in April due to hotter weather.

“The virus... typically that will go away in April,” he told reporters at the White House, adding: “The heat, generally speaking, kills this kind of virus.”

The SARS-like pathogen has infected 40,000 people since its emergence in China late last year, while the United States has seen 12 confirmed cases of varying severity.

Trump praised China—and its leader Xi Jinping—for the Asian giant’s efforts in containing the spread.

“(I) had a long talk with President Xi... two nights ago,” Trump said.

“He feels very confident... (that) during the month of April, the heat, generally speaking, kills this type of virus. That would be a good thing.” 

For reasons that aren’t fully understood, flu-like viruses tend to thrive in colder, dryer seasons and the new coronavirus could follow suit—putting a brake on the outbreak with the arrival of milder weather.

But Trump’s prognosis is at odds with top US health officials who have cautioned against commenting on the trajectory of the epidemic.

“The issue is, we don’t know,” Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told reporters Friday. 

“And any kind of prediction would be ill-advised because we really have so many unknowns,” he added.

He said that in the “best scenario” the Chinese would contain the outbreak and there would be a stop to its international spread.

But he added that China could fail to control the outbreak or, even if it were successful, the virus could spread to a country without the resources to trace contacts and isolate new cases.

A January 31 paper in British medical journal The Lancet warned that, even if the epidemic begins to recede at its epicenter in the central Chinese city of Wuhan in April, it could still grow globally into the second half of the year.