Holiday travel at Orange County, California’s John Wayne Airport appeared grounded as officials reported a 75 percent drop in the preliminary number of passengers for December. “John Wayne Airport has faced unprecedented challenges in 2020,” airport director Barry Rondinella said in a statement. “Through it all, the airport team has gone above and beyond to protect the health and safety of our guests, tenants, and employees. We remain committed to ensuring a safe and convenient travel experience for all of our guests.”           Meantime, a California Department of Public Health advisory encourages out-of-state visitors to self-quarantine for 14 days after landing. A spokesperson for John Wayne Airport said that the airport abides by all CDC guidelines and air travelers are informed of recommended safety measures, including signs in the terminals, and announcements by the Orange County Health Care Agency over the airport intercom.   On Dec. 30, …