Arizona reported 636 new COVID-19 cases and 12 new known deaths on Saturday as hospital metrics for the disease remain relatively stable.

Identified cases rose to 220,399 and known deaths are at 5,705, according to the daily report from the Arizona Department of Health Services. 

The number of patients hospitalized statewide for known or suspected COVID-19 was at 605 on Friday, up from Thursday’s 586. That was down from Wednesday’s 620 inpatients, which was an uptick from 560 inpatients on Tuesday, 540 on Monday and 468 on Sunday. Inpatient numbers look to be possibly plateauing and increasing slightly, but more time is needed to point to a trend. During the peak of Arizona’s surge in July, the number of hospitalized patients suspected or confirmed to have the virus exceeded 3,000.

The number of patients with suspected or known COVID-19 in intensive care units across Arizona was at 127 on Friday, continuing a two-week-long plateau at about that level. The level is also far below what it was in July, when ICU beds in use for COVID-19 reached 970.

The number of Arizonans with confirmed and suspected COVID-19 on ventilators was at 52 on Friday, a slight increase from Thursday’s count of 48. The metric has hovered around that level for about a week and a half. In mid-July, as many as 687 patients across the state with confirmed or suspected COVID-19 were on ventilators. 

The Department of Health Services has begun including as probable cases anyone with a positive antigen test, another type of test to determine current infection. Antigen tests (not related to antibody tests) are a newer type of COVID-19 diagnostic test that use a nasal swab or other fluid sample to test for current infection. Results are typically produced within 15 minutes. 

A positive antigen test result is considered very accurate, but there’s an increased chance of false-negative results, the Mayo Clinic says. Depending on the situation, Mayo Clinic officials say a doctor may recommend a PCR (polymerase chain reaction) test to confirm a negative antigen test result. 

Friday’s dashboard shows 83% of inpatient beds and 78% of ICU beds in use, which includes people being treated for COVID-19 and other patients. COVID-19 patients were using 7% of all inpatient beds and 8% of ICU beds. Overall, 24% of ventilators were in use.

The number of weekly tests conducted dropped significantly in July and into August, after which it has remained flatter with some fluctuation.

Of known test results from the past four weeks, 4% have come back positive, according to the state, which has a unique way of calculating percent positivity.

Johns Hopkins University calculates Arizona’s seven-day moving average of percent positives at 6.1% and shows it has generally trended downward in recent weeks but has reached a plateau.

A positivity rate of 5% is considered a good benchmark that the spread of the disease is under control.

Here’s what you need to know about Saturday’s new numbers: 

Reported cases in Arizona: 220,399

• Cases increased by 636, or 0.29%, from Friday’s 219,763 identified cases since the outbreak began.
• Cases by county: 142,968 in Maricopa, 25,855 in Pima, 12,815 in Yuma, 10,717 in Pinal, 5,818 in Navajo, 4,263 in Coconino, 4,048 in Mohave, 3,579 in Apache, 2,881 in Santa Cruz, 2,609 in Yavapai, 1,918 in Cochise, 1,444 in Gila, 877 in Graham, 548 in La Paz and 59 in Greenlee, according to state numbers.
• The rate of cases per 100,000 people is highest in Yuma County, followed by Santa Cruz, Navajo and Apache counties. The rate in Yuma County is 5,564 cases per 100,000 people. By comparison, the U.S. average rate is 2,180 cases per 100,000 people, according to the U.S. Centers for Disease Control and Prevention.
• The Navajo Nation reported 10,369 cases and 556 confirmed deaths as of Thursday. The Navajo Nation includes parts of Arizona, New Mexico and Utah.
• The Arizona Department of Corrections said 2,587 inmates had tested positive for COVID-19 as of Friday, including 976 in Tucson; 40,050 inmates statewide have been tested; and five total test results are pending in the state prison system. A total of 708 prison staff members have self-reported testing positive, the state corrections department said. Seventeen incarcerated people in Arizona have been confirmed to have died of COVID-19, with 11 additional deaths under investigation. 
• While race/ethnicity is unknown for 31% of cases statewide, 31% of cases are Hispanic or Latino, 25% are white, 6% are Native American, 3% are Black and 1% are Asian/Pacific Islander.
• Laboratories have completed 1,488,145 diagnostic tests for COVID-19, 11% of which have come back positive. That number now includes both PCR and antigen testing. The percentage of positive tests had increased since mid-May but began decreasing in July and for the past four weeks has been at 4%. The state numbers leave out data from labs that do not report electronically.
• Arizona as of Thursday had one of the highest overall rates of COVID-19 infection in the country — fifth behind Louisiana, Mississippi, Florida and Alabama. Arizona’s infection rate is 3,047 cases per 100,000 people, the CDC says. The national average is 2,180 cases per 100,000 people, though the rates in states hard-hit early on in the pandemic may be an undercount due to a lack of available testing in March and April.

Reported deaths: 5,705 known deaths

• On Saturday, 12 new known deaths were reported.
• County deaths: 3,424 in Maricopa, 627 in Pima, 348 in Yuma, 236 in Navajo, 229 in Mohave, 210 in Pinal, 165 in Apache, 144 in Coconino, 84 in Yavapai, 73 in Cochise, 63 in Santa Cruz, 60 in Gila, 25 in Graham, 15 in La Paz and fewer than three in Greenlee.
• People aged 65 and older made up 4,057 of the 5,705 deaths, or 71%.
• While race/ethnicity is unknown for 11% of deaths, 42% of those who died were white, 30% were Hispanic or Latino, 10% were Native American, 3% were Black and 1% were Asian/Pacific Islander, the state data show.
• The COVID-19 death rate in Arizona was 78 per 100,000 people as of Thursday, according to the CDC, putting it 10th in the country in a state ranking that separates New York City and New York state. The U.S. average is 62 deaths per 100,000 people, the CDC says.
• Behind New York City, at 283 deaths per 100,000 people, the CDC placed the highest death rates ahead of Arizona as New Jersey, Massachusetts, Connecticut, Louisiana, Rhode Island, Mississippi, the District of Columbia and New York state.

Reach the reporter at [email protected] or 602-444-8529.  Follow her on Twitter @brieannafrank. 

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