The growing impact that COVID-19 is having on Arizona is coming in waves.
Arizona has fifteen demographically diverse counties that vary in population from only 9,504 people in Greenlee to 4,253,913 in the state’s most populous county Maricopa.
Most of the state’s 29,852 COVID-19 cases occur in the urban counties of Maricopa and Pima, but the pandemic has affected a larger portion of the population in the smaller counties, and at different times.
To analyze COVID-19 over the course of time in the counties, ABC15 looked at the pandemic using cases per 1 million residents. While only two of the state’s counties have populations over a million, the formula equalizes the numbers throughout the state.
The pandemic began early in Maricopa County but quickly shifted to the northern counties that encompass the borders of the Navajo Nation, one of the hardest hit areas in the country.
Northern counties continued to diverge from the rest of the state, with central and southern counties feeling the virus’s impact at about the same rate.
Arizona is going through a second wave of coronavirus, with case counts rising by 50% in the past 10 days.
This wave has disproportionately impacted two the state’s border counties. Since June 1, COVID-19 cases in Yuma county have risen 120%, Santa Cruz 108%.
The graph below shows the case per million growth of COVID-19 with the state’s counties colored by region.