Arizona is now securely in a period of substantial (versus high) risk with continuing, albeit smaller, improvements in case counts expected over the coming weeks. Hospital capacity remains adequate to meet Arizona’s foreseeable needs; however, the backlog of non-Covid care has yet to be fully addressed as evidenced by unseasonably high hospital occupancy.

While residents and businesses should continue to follow public health mitigation recommendations, normalization of lower risk activities is reasonable as case rates have fallen below 100 new diagnoses per 100,000 residents per week. New cases are now being diagnosed at a rate of 79 per 100K residents per week. For reference, September 8^th marked the fall nadir between the summer and winter outbreaks at 38 per 100K per week. Arizonans who are at risk of developing severe disease (e.g., age or comorbid conditions) should remain sheltered as much as feasible until fully vaccinated.

Note: Data for this report was updated Friday, March 12 allowing 4 full days to adjudicate cases and keep week-over-week backfill <10%. This allows more interpretable comparisons and graphics. All comparisons are week-over-week changes. Future updates will be released on Saturdays.

Test positivity among those undergoing traditional nasopharyngeal PCR testing continues to decline, declining from 10% the week ending February 28th to 9% the week ending March 7th (Figure 3). Positivity is now within the recommended 5 – 10% for optimal public health practice.

As of March 12th, 814 (10%) of Arizona’s 8557 general ward beds were occupied by Covid-19 patients, a 16% decrease from the previous week’s 966 occupied beds (Figure 4 and Figure 5 Panel A). Another 1011 (12%) beds remained available for use. The number of available beds is higher than the previous week’s 952 beds.

Covid-19 occupancy has dropped by 84% from its January 11^th peak of 5082 ward patients. Nevertheless, hospitals remain above seasonal occupancy.

As of March 12th, 238 (14%) of Arizona’s 1750 ICU beds were occupied with Covid-19 patients, a 15% decrease from the prior week’s count of 280 patients (Figure 4 and Figure 5 Panel B). An additional 262 (15%) ICU beds remained available for use. This is similar to the prior week’s 263 available beds. ICU occupancy has fallen 80% from its January 11^th peak of 1183 occupied beds.

While Arizona hospitals’ safety margins remain low, they are slowly improving (Figure 6). Medically necessary procedures are now being scheduled in a more typical manner. The backlog of postponed care will take several more months to resolve. As capacity constraints are lessened, care practices should return to those prior to the outbreak ensuring all patients will receive optimal care. Hospitals will remain crowded through early April before returning to pre-outbreak levels assuming continued reductions in viral transmission.

The week ending January 17th remains Arizona’s deadliest with 1032 deaths (Figure 7). The week of January 17^th represents peak mortality with subsequent improvements for the foreseeable future. Covid-19 deaths are expected to remain high for the next 1 - 2 weeks, falling below 200 per week by the end of March.

For the week ending March 7th, 684 Pima County residents were diagnosed with Covid-19, a 17% decrease from the 826 cases initially reported last week (Figure 8). Last week’s initial tally was downwardly revised by 5% (41 cases) to 785 cases.

New cases are being diagnosed at a rate of 65 cases per 100K residents per week. For reference, October 9^th marked a nadir between the summer and winter outbreak at 46 cases per 100K residents per week. Trends are similar across the various age groups (Figure 9).