But day after day, Dr. Tedros, in his rambling style, was delivering less formal warnings, telling countries to contain the virus while it was still possible, to do testing and contact tracing, and isolate those who might be infected. “We have a window of opportunity to stop this virus,” he often said, “but that window is rapidly closing.”
In fact, the organization had already taken steps to address the coronavirus, even before Dr. Zhong’s awful revelation, drawing attention to the mysterious outbreak.
On Jan. 12, Chinese scientists published the genome of the virus, and the W.H.O. asked a team in Berlin to use that information to develop a diagnostic test. Just four days later, they produced a test and the W.H.O. posted online a blueprint that any laboratory around the world could use to duplicate it.
On Jan. 21, China shared materials for its test with the W.H.O., providing another template for others to use.
Some countries and research institutions followed the German blueprint, while others, like the Centers for Disease Control and Prevention in the United States, insisted on producing their own tests. But a flaw in the initial C.D.C. test, and the agency’s slowness in approving testing by labs other than its own, contributed to weeks of delay in widespread testing in the United States.
In late January, Mr. Trump praised China’s efforts. Now, officials in his administration accuse China of concealing the extent of the epidemic, even after the crackdown on Wuhan, and the W.H.O. of being complicit in the deception. They say that lulled the West into taking the virus less seriously than it should have.