Based on cases from Sept. 10-23, the Navajo Department of Health issued an advisory for 40 communities due to an uncontrolled spread of COVID-19. The tribe’s reservation is the country’s largest at 27,000 square miles (70,000 square kilometers) and it …Based on cases from Sept. 10-23, the Navajo Department of Health issued an advisory for 40 communities due to an uncontrolled spread of COVID-19. The tribe’s reservation is the country’s largest at 27,000 square miles (70,000 square kilometers) and it …