Several large business groups on Thursday said President Joe Biden’s latest COVID-19 vaccine requirement was poorly planned and would burden employers during the holiday season. The mandate, announced by Biden in September, was released to the public for the first time on Nov. 4. It requires employers with 100 or more employees—and, perhaps, smaller businesses—to secure proof of COVID-19 vaccination from workers or force them to get tested for the disease on a regular basis, at least once a week. David French, a senior vice president at the National Retail Foundation, said retailers have taken “extraordinary measures” during the pandemic to protect employees and customers, including encouraging and mandating vaccination. “Since the president’s announcement of the vaccine mandate for private industry, the seven-day average number of cases in the United States has plummeted by more than half. Nevertheless, the Biden administration has chosen to declare an ‘emergency’ and impose burdensome …