Doctors Without Borders is rushing aid to combat a huge surge of COVID-19 cases in the Navajo Nation, a region with some of the highest rates of infection in the country. This is the first time that the organization of medical professionals, which has teams in Iran and Afghanistan, has ever had a presence in the United States.

The Navajo Nation, in the U.S. southwest and home to around 170,000, now has more COVID-19 cases per capita than any other state in America. Residents in Navajo Nation are already high-risk since Navajo people carry a high-risk for diabetes and hypertension. The region has had more COVID-19 deaths than 46 U.S. states.

The head of the organization’s U.S. COVID-19 Response Team told CBS News that the Navajo Nation is at high-risk because “they don’t have access to the variety of things to self-isolate. You can’t expect people to isolate if they have to drive 100 miles to get food and water.” 1 in 3 Navajo Nation residents lack access to running water.