Mokdad pointed to a number of factors that have made both North and South Dakota vulnerable to the virus’ spread. He cited higher rates of preexisting conditions and economic inequality in the region, in addition to health care that lags behind the U.S. standard.

But the lack of regulation from the states’ leaders is an ongoing and fixable problem, Mokdad said.

Haseltine, president of ACCESS Health International and author of My Lifelong Fight Against Disease, blamed politicians — especially South Dakota Republican Gov. Kristi Noem — for ignoring public health measures that have been successfully used to curb the spread of the virus elsewhere in the world.

Noem has cast doubt on whether wearing masks in public is effective, saying that she’ll leave it up to the people to decide. She has said the virus can’t be stopped.