The Indian Health Service updated its coronavirus testing data, showing results as of 11:59 pm Eastern on June 15, 2020.

According to the data, 15,487 tests have returned returned positive for COVID-19, the disease caused by the coronavirus. That represents an increase of 1.7 percent from the 15,218 cases reported on June 14 and an increase of 1.6 percent from the 15,241 cases reported on June 13.

But for reasons that have not been explained by the IHS, the number of positive cases was adjusted downward between June 13 and June 14.

Altogether, 197,700 coronavirus tests have been administered within the IHS through June 15. That represents an increase of about 2.3 percent increase from June 14 and an increase of 1.7 percent from June 13.

Again, for reasons that have not been explained by the IHS, the number of tests administered was adjusted downward between June 13 and June 14.

Overall, 7.8 percent of IHS coronavirus tests are returning positive, the data shows. But the rate is far higher, about 21.1 percent, in the Navajo Area, which serves the largest reservation in the United States.

The Phoenix Area, with nearly 18.6 percent of tests returning COVID-19 positive, and the Nashville Area, with 13 percent positive, are also higher than the IHS national rate.

The data from Phoenix Area, though, shows significant discrepancies. The IHS lowered the number of reported tests from 27,118 to 16,510 between June 13 and June 14. However, the number of positive cases stayed largely the same, which accounts for the large spike in the positive test rate.

On the other end of the spectrum, aggressive efforts in the Alaska Area are turning up very few cases. Out of 29,764 tests administered in Alaska, only 0.23 returned positive, the data shows.

The data, however, is incomplete. While 100 percent of facilities run directly by the IHS are reporting data, only 33 percent of tribally managed facilities and 44 percent of urban Indian organizations are doing the same, the agency has told Indianz.Com.

The agency also provided to Indianz.Com the service population for 2019: 2,562,290. Based on that figure, 7.7 percent of American Indians and Alaska Natives have been tested for the coronavirus since the IHS began reporting data in March.

The IHS user population, on the other hand, is a much smaller number. As of 2019, 1,662,834 American Indians and Alaska Natives have lived within a service delivery area and have received health care at an IHS or tribal facility during the previous three years.

Based on the user population, 11.9 percent of Native Americans have been tested for the coronavirus since the IHS began reporting data in March.

COVID-19 Cases by IHS Area

Data are reported from IHS, tribal, and urban Indian organization facilities, though reporting by tribal and urban programs is voluntary. Data reflect cases reported to the IHS through 11:59 pm on June 15, 2020.

IHS: https://www.ihs.gov/coronavirus/

IHS COVID-19 Dashboard