"We need to remember that we're still facing significant risk of spread among people who are at risk for complications, so just want to take the foot off the brake carefully," McClellan told the American-Statesman, speaking in his first interview since Abbott announced last week that he was ending his statewide mask mandate and business restrictions, effective Wednesday. "At some point, you hit a place where the rapidity at which you're vaccinating starts to tail off," said Zerwas, a former Republican state legislator and executive vice chancellor for health affairs at the University of Texas System, adding that the state is expecting a certain percentage of people in each eligible group will decline to be vaccinated.