It's the first time since July that the state has been fire-free. "That's more than 240 days of fire activity" across the country's most populous state, New South Wales Rural Fire Service said.

The tests will likely find infections around the country — including cases that had gone undetected. The CDC says it has enough kits to test at least 75,000 people and that more are on order.

"We have never before seen a respiratory pathogen that is capable of community transmission but which can also be contained with the right measures," the WHO's Tedros Adhanom Ghebreyesus said.

A criminal case in Houston alleges that employees at a chemical company should have prepared for the record flooding caused by Hurricane Harvey.