Texas Gov. Greg Abbott tested positive for COVID-19 on Tuesday despite being fully vaccinated against the virus, his office said.

The Republican was isolating at the Governor’s Mansion in Austin and receiving a monoclonal antibody treatment from biotech company Regeneron, according to his communications director Mark Miner.

“Governor Abbott is fully vaccinated against COVID-19, in good health, and currently experiencing no symptoms,” Miner said in a statement. “Everyone that the governor has been in close contact with today has been notified.”

Abbott, 63, recently imposed a ban on mask mandates in the Lone Star State. Last week, he vowed to take to court any school district, public university or local official who rejects his order.