Tuba City Regional Health Care’s RV-size mobile medical clinic is parked on a small, vacant lot on the border of the Navajo Nation and the Hopi Tribe it surrounds. It provides COVID-19 vaccines, Pfizer and Moderna boosters to adults and now shots for …Tuba City Regional Health Care’s RV-size mobile medical clinic is parked on a small, vacant lot on the border of the Navajo Nation and the Hopi Tribe it surrounds. It provides COVID-19 vaccines, Pfizer and Moderna boosters to adults and now shots for …