MADISON, Wisconsin — Cardinal Raymond Burke, one of the Catholic Church’s most outspoken conservatives and a vaccine skeptic, said he has COVID-19 and his staff said he is breathing through a ventilator.

Burke tweeted Aug. 10 that he had caught the virus, was resting comfortably and was receiving excellent medical care.

“Please pray for me as I begin my recovery,” the 73-year-old Burke said in the tweet. “Let us trust in Divine Providence. God bless you.”

On Saturday, his staff tweeted that he has been hospitalized and is on a ventilator, but that doctors were encouraged with his progress.

“(His Eminence) faithfully prayed the Rosary for those suffering from the virus … Let us now pray the Rosary for him,” his staff said.

The Washington Post and the St. Louis Post-Dispatch reported that Burke became infected during a visit to Wisconsin and was hospitalized there. Burke was born in Richland Center in southwestern Wisconsin and served as bishop in the Diocese of La Crosse from 1995 to 2004.

COVID-19 cases have been surging in Wisconsin in recent weeks due largely to the delta variant. The state’s seven-day case average stood at 1,139 as of Wednesday, the highest it’s been since February.

The Diocese of La Crosse referred questions Monday about Burke’s location and condition to the Shrine of Our Lady of Guadalupe, a shrine Burke founded in the city. A message left there wasn’t immediately returned. A spokesman for the Wisconsin Hospital Association said he had no information on Burke. Vatican media officials didn’t immediately respond to an email.

Burke holds a doctorate in canon law. He moved from the Diocese of La Crosse to become archbishop of St. Louis. He spent more than four years in that position, leaving in August 2008 to oversee the Vatican’s supreme court. He was the first American to hold that position.

Burke has built a reputation as an outspoken conservative. He drew attention in the U.S. in 2004 when he said he would deny Holy Communion to the Democratic presidential nominee, John Kerry, a pro-choice Catholic.

Pope Francis reassigned Burke from the Vatican court in 2014 after he said the church was like a ship with no rudder.

Burke has since become one of Francis’ fiercest critics, first by joining three other conservative cardinals in formally asking Francis in 2016 to explain himself after he opened the door to letting civilly remarried Catholics receive Holy Communion.

He also has joined a chorus of conservative and traditionalist criticism of Francis’ crackdown on the celebration of the old Latin Mass, decrying the “severity” of the pope’s decision and questioning his right to impose, saying he shared the “profound sorrow” of Catholics who felt Francis had unfairly attacked them. Burke celebrated a Tridentine Mass, as the old liturgy is also known, at a parish in Stamford, Connecticut, the very evening that the pope’s new restrictions were announced.

The pope eventually placed him back on the court in 2017 but made him a member rather than its chief officer.

Burke criticized the University of Notre Dame, in 2009, over its plans to give then-President Barack Obama an honorary degree because Obama supports abortion rights.

Burke also has criticized how governments have handled the pandemic, referring to the virus in a homily last December as the “Wuhan virus,” a derogatory term used by former President Donald Trump to describe the coronavirus and warning people that governments were manipulating them. In May 2020, he spoke out against mandatory vaccinations, saying some in society want to implant microchips in people.

He said in March 2020 that the best weapon for battling “the evil of the coronavirus” is a relationship with Jesus Christ.

Associated Press reporters Jim Salter in O’Fallon, Missouri, and Nicole Winfield in Rome contributed to this report.