March has never seen such madness. The NCAA made the...

Mayor Bill de Blasio directly contradicted Centers for Disease Control and Prevention guidelines on Wednesday when he gave a woman who’d recently returned from coronavirus-ridden Italy bad advice on when to self-isolate.

Hizzoner dished out the dubious tip while fielding a call at a 311 center in Lower Manhattan, as reporters looked on.

“No symptoms of any kind?” de Blasio asked the unidentified caller, who had recently come back from a trip to Europe’s hardest-hit nation but not shown any signs of sickness. “If you experience any symptoms at any moment, at that time adjust your approach.

“The important thing is to really be sensitive that if anything changes at all stay home immediately.”

The CDC, however, advises that anyone returning stateside from Italy self-isolate for two weeks — regardless of whether they’re symptomatic.

“Stay home for 14 days from the time you left Italy and practice social distancing,” the agency writes on its website.

City Hall admitted de Blasio was wrong and said it had reached out to the caller to give her the right information, following an inquiry from The Post.

“The mayor misspoke,” spokeswoman Freddi Goldstein said. “If you return from Italy you should self-quarantine regardless of symptoms. We have made contact with the caller and clarified and the mayor will be issuing a clarification, as well.”

As of Wednesday afternoon, there were 212 confirmed cases across the state, with 48 in the five boroughs.