Sign up for The Brief, the Texas Tribune’s daily newsletter that keeps readers up to speed on the most essential Texas news. A sweeping ban on COVID-19 vaccine requirements for all private businesses, including hospitals, is the latest blow to medically vulnerable Texans who rely on others’ immunization to shield themselves from highly transmissible viruses. Tamer coronavirus variants and a soft vaccine booster rollout have contributed to a lessened sense of urgency around the virus.