WASHINGTON, Feb. 21 (USA Today) - After chaos for a cruise ship of passengers and crew, an 83-year-old American woman who was said to have tested positive for coronavirus in Malaysia "never had coronavirus to our knowledge," the CDC told USA TODAY late Friday.

"I have confirmed that all the passengers were tested, and they have come back negative for coronavirus, including the person who initially tested positive," said CDC spokesperson Richard Quartarone. He added that the hospitalized woman "may have had a respiratory illness, but if she did, it was not COVID-19."

The CDC received those results Thursday, said Quartarone. He said the CDC sent revised guidance to state and local health officials late Thursday based on those results.

If Westerdam passengers "have questions or think they shouldn't self-quarantine and were told to (do so) by their local health. department, follow up with your local health department," he advised.