What does COVID-19 look like going into Christmas in Arizona?

Posted at 5:23 PM, Dec 21, 2021

Weekend reporting lag typically means that Tuesday is when a clearer picture of COVID-19 trends will look like for the week emerges.

ABC15 analyzed the latest COVID-19 data across the state to see what the situation looks like heading into the holiday weekend.

COVID-19 case numbers have been flat for most of December.

Arizona began the month with a 7-day average of newly added cases around just under 3,000 cases.

The trend quickly rose to a peak of just above 4,000 but have fallen back to where they were at the start of the month. This is a stark contrast to last year when COVID-19 daily case averages continued to rise to around 6,000.

Made with Flourish

The rise and fall of case numbers in December mirrors similar movement in the number of diagnostic tests conducted daily. The estimated positivity rate of daily reported diagnostic tests began the month at 13.2% before rising as high as 14.7% on December 13. The rate has fallen since to around 12.4%.

Arizona’s hospital capacity is still stretched thin.

Hospitals report 495 inpatient beds are empty out of 8,791 licensed beds statewide. Hospital systems are reporting only 79 ICU beds are empty.

There has been a slight let up in COVID-19 hospitalizations, with inpatient beds falling about 8% from where it was last week, while ICU beds remained steady with only a 1% increase from last week.

Made with Flourish

Health officials reported 223 new COVID-19 deaths, the ninth highest reported number on record. Most of the deaths are recent, occurring mostly in the past two weeks.

Arizona is averaging about 71 COVID-19 deaths a day. Based on other reported metrics, this could turn out to be close to the peak of deaths in the short term.

Since COVID-19 deaths lag behind all other data points, the overall movement of the trendline can be observed by laying cases, hospitalizations, and deaths together, removing the lag and using the COVID-19 case fatality rate to fit the other trends to the chart.

COVID-19 deaths remain correlated tightly, meaning if other metrics continue to fall, COVID-19 deaths will follow.

Made with Flourish

What could omicron do?

Early data strongly suggests that the omicron variant will out-compete delta quickly.

The CDC recently modeled out variant sequencing and determined that omicron is already the dominant variant in the US this week at 73% of sequences. HHS region 9, where Arizona is located at, modeled omicron at 60% of COVID-19 infections.

Unmodeled data from T-GEN still shows omicron at only 1.6% of sequenced variants in Arizona. If it eventually out-competes delta in Arizona, expect a sharp rise in COVID-19 cases.

Data further suggests that omicron infections is milder for most, but with Arizona’s hospital systems still at 95% capacity, even a lower hospitalization rate of new infections could become problematic.