Arizona reports 645 new COVID-19 cases, 16 new known deaths as metrics remain stable

Arizona on Saturday reported 645 new COVID-19 cases and 16 new known deaths, continuing a trend of stable and relatively low metrics across the state.

Arizona's seven-day case rate per 100,000 people ranked 29th on Friday among all states and territories after ranking first and second for much of January, according to the Centers for Disease Control and Prevention's COVID Data Tracker.

Arizona ranked 51st among 60 states and territories on March 28, but its rank has fluctuated.

Arizona's seven-day death rate per 100,000 people ranked 31st in the nation as of Friday, according to the CDC.

Percent positivity, which refers to the percent of COVID-19 diagnostic tests that are positive, varies somewhat based on how it's measured.

Last week, Arizona's percent positivity was at 5% after four weeks at 6%, according to the state, which has a unique way of calculating percent positivity. Weekly percent positivity statewide peaked at 25% in December.

Johns Hopkins University calculates Arizona's seven-day moving average of percent positives at 3.2% as of Saturday. It shows the state's percent positivity peaked at 24.2% in December.

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

The state's overall COVID-19 death and case rates since Jan. 21, 2020, still remain among the worst in the country.

The COVID-19 death rate in Arizona since the pandemic began is 240 deaths per 100,000 people as of Friday, according to the CDC, putting it sixth in the country in a state ranking that separates New York City from New York state. The U.S. average is 176 deaths per 100,000 people as of Friday, the CDC said.

New York City has the highest death rate, at 393 deaths per 100,000 people, followed by New Jersey, Massachusetts, Rhode Island and Mississippi.

Arizona's case rate per 100,000 people since the pandemic began remained ranked sixth nationwide as of Friday.

Arizona's known COVID-19 death count rose to 17,547 after 16 new known deaths were reported Saturday. 

The state surpassed 17,000 deaths on April 7, after passing 16,000 deaths on March 2, 15,000 deaths on Feb. 17, 14,000 deaths on Feb. 6 and 13,000 deaths on Jan. 29, just one week after it passed 12,000 and two weeks after 11,000 deaths. The state exceeded 10,000 known deaths on Jan. 9. Arizona's first known death from the disease occurred in mid-March 2020.

Many of the reported deaths occurred days or weeks prior because of reporting delays and death certificate matching.

A total of 876,411 COVID-19 cases have been identified across the state. March, April and May have seen relatively lower case reports. 

The Arizona data dashboard shows 85% of all ICU beds and 88% of all inpatient beds in the state were in use Friday, with 9% of ICU beds and 7% of non-ICU beds occupied by COVID-19 patients. Statewide, 255 ICU beds and 1,029 non-ICU beds were available. 

Hospitalizations for the disease generally dropped for about 13 weeks and recently appear to have plateaued somewhat. However, there was a slight uptick since April 25, when the total number of COVID-19 inpatients hospitalized statewide eclipsed 600 for the first time since March 31. Hospitalizations remained at more than 600 for 13 consecutive days through May 7 and then stayed below 600 from May 8, with the exception of May 18, when the count was 607.

The total number of patients hospitalized in Arizona for known or suspected COVID-19 cases was at 573 on Friday, down from 581 on Thursday and still far below the record 5,082 inpatients on Jan. 11. The highest number of COVID-19 hospitalizations in a single day during the summer 2020 surge was 3,517 on July 13.

The number of patients with suspected or known COVID-19 in ICUs across Arizona was at 160 on Friday, down from 167 on Thursday and far below the record high of 1,183 on Jan. 11. During the summer surge in mid-July, ICU beds in use for COVID-19 peaked at 970.

Arizonans with confirmed and suspected COVID-19 on ventilators tallied 64 on Friday, down from 68 on Thursday and well below the record high 821 reached on Jan. 13. During the summer surge, July 16 was the peak day for ventilator use, with 687 patients.

Friday saw 950 patients in Arizona emergency rooms for COVID-19, well below the Dec. 29 single-day record of 2,341 positive or suspected COVID-19 patients seen in emergency departments across the state.

Arizona began its first COVID-19 vaccinations for health care workers, long-term care facilities and front-line first responders in mid-December. The state in early March shifted to a largely age-based rollout and in late March began allowing anyone 16 and older to start registering for appointments. And Arizonans ages 12 through 15 are now eligible to get the Pfizer vaccine. 

The state reported nearly 3.2 million people in Arizona had received at least one vaccine dose as of Saturday, with more than 2.7 million people fully vaccinated against COVID-19. 

What to know about Saturday's numbers

Reported cases in Arizona: 876,411.

Cases since the outbreak began increased by 645 or 0.07%, from Friday's 875,766 identified cases. These daily cases are grouped by the date they are reported to the state health department, not by the date the tests were administered. 

Cases by county: 547,035 in Maricopa, 116,276 in Pima, 52,559 in Pinal, 37,195 in Yuma, 22,935 in Mohave, 19,134 in Yavapai, 17,871 in Coconino, 16,376 in Navajo, 12,052 in Cochise, 11,381 in Apache, 8,020 in Santa Cruz, 6,919 in Gila, 5,610 in Graham, 2,472 in La Paz and 574 in Greenlee, according to state numbers.

The rate of cases per 100,000 people since the pandemic began is highest in Yuma County, followed by Apache, Santa Cruz, Graham and Navajo counties, per state data. The rate in Yuma County is 16,175 cases per 100,000 people. By comparison, the U.S. average rate since the pandemic began is 9,896 cases per 100,000 people as of Friday, according to the CDC.

The Navajo Nation reported 30,753 cases and 1,297 confirmed deaths in total as of Friday. The Navajo Nation includes parts of Arizona, New Mexico and Utah.

The Arizona Department of Corrections reported 12,307 inmates had tested positive for COVID-19 as of Friday, including 2,243 in Tucson, 2,032 in Eyman, 2,014 in Yuma, 1,303 in Lewis and 1,163 in Douglas; 47,279 inmates statewide have been tested. A total of 2,772 prison staff members have self-reported testing positive, the department said. Forty-nine incarcerated people in Arizona have been confirmed to have died of COVID-19, with 10 additional deaths under investigation.

Race/ethnicity is unknown for 17% of all COVID-19 cases statewide, but 38% of positive cases have been diagnosed in white people, 30% Hispanic or Latino, 5% Native American, 3% Black and 1% Asian/Pacific Islander.

Of those who have tested positive in Arizona since the start of the pandemic, 16% were younger than 20, 44% were 20-44, 15% were 45-54, 12% were 55-64 and 13% were age 65 or older.

Laboratories had completed 4,388,280 diagnostic tests on unique individuals for COVID-19 as of Saturday, 13.1% of which have come back positive. That number includes both PCR and antigen testing. The percentage of positive tests for the last full week was at 5%, following four weeks at 6%. The state numbers leave out data from labs that do not report electronically.

The state health department includes probable cases as anyone with a positive antigen test, another type of test to determine current infection. Antigen tests (not related to antibody tests) use a nasal swab or another 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. Mayo Clinic officials say a doctor may recommend a PCR (polymerase chain reaction) test to confirm a negative antigen test result. 

Arizona as of Friday had the sixth-highest overall case rate in the country since Jan. 21, 2020. Ahead of Arizona in cases per 100,000 people since the pandemic began are North Dakota, Rhode Island, South Dakota, Utah and Tennessee, according to the CDC.

Arizona's infection rate is 12,016 cases per 100,000 people, according to the CDC. The national average is 9,896 cases per 100,000 people, though the rates in states hard hit early in the pandemic may be an undercount because of a lack of available testing in March and April 2020.

Reported deaths in Arizona: 17,531

Deaths by county: 10,001 in Maricopa, 2,409 in Pima, 887 in Pinal, 838 in Yuma, 727 in Mohave, 536 in Navajo, 508 in Yavapai, 432 in Apache, 332 in Coconino, 287 in Cochise, 230 in Gila, 180 in Santa Cruz, 82 in Graham, 79 in La Paz and 10 in Greenlee.

People age 65 and older make up 13,125 of the 17,547 deaths, or 75%. Following that, 15% of deaths were in the 55-64 age group, 6% were 45-54 and 4% were 20-44 years old.

While race/ethnicity was unknown for 6% of deaths, 50% of those who died were white, 28% were Hispanic or Latino, 8% were Native American, 3% were Black and 1% were Asian/Pacific Islander, the state data show.

The global death toll as of Friday morning was 3,445,264. The U.S. had the highest death count of any country in the world, at 589,242, followed by Brazil at 446,309 and India at 295,525, according to Johns Hopkins University. Arizona's death total of 17,531 deaths represents about 3% of COVID-19 deaths in the U.S.

Reach the reporter at bfrank@arizonarepublic.com or 602-444-8529.  Follow her on Twitter @brieannafrank. 

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