Gov. Tim Walz is out of quarantine after he, his wife and their teenage son tested positive for breakthrough COVID-19 just before the holidays.

The governor said Monday that the family recently tested negative after confirming on Dec. 20 that they had contracted the virus. Walz and his wife, Gwen, are vaccinated and have received booster shots. Their son, Gus, who is also vaccinated, was the first in the family to experience cold-like symptoms.

"We had our 15-year-old, a public school student, test positive, which is not that unusual for families out there, and then Gwen and I did," Walz said in a Monday morning interview on MPR News. "The good news is we had been able to test and we were able to quarantine."

Walz said the family experienced "mild to moderate" symptoms and their COVID-19 cases prevented them from seeing their college-age daughter and other family members over the holidays.

It was the first time Walz tested positive for the coronavirus, although he has needed to quarantine after past exposures. Lt. Gov. Peggy Flanagan, who is vaccinated, contracted the virus in October after her school-aged daughter tested positive.

Walz used his own case to encourage Minnesotans to get tested as the highly contagious omicron variant of the virus continues to surge in Minnesota.

"Even if you're feeling like it's mild symptoms and it feels like it might be a cold, which it was in our case, the test proved that it was COVID, which allowed us to isolate and not spread it to my 87-year-old mother, my wife's family, things like that," he said.

The governor applauded President Joe Biden's move to provide 500 million free at-home COVID-19 tests, but Walz acknowledged the influx of tests complicates already-strained supply chains to Minnesota. He asked Minnesotans to be patient and said the state was still in better shape than most of the country after adopting an early testing system.

"We have a robust system," Walz said. "The good news now is people are using it; they understand this testing is important. The bad news is the supply chains are still strained nationally."