Overall, cases are being diagnosed at a rate of 57 per 100K residents per week. For reference, September 8^th marked the fall nadir between the summer and winter outbreaks at 38 cases per 100K residents per week. The post-holiday nadir was 54 cases per 100K residents on March 23, 2021. Over the next 1 – 3 weeks, case rates may fall below the 50 cases per 100K residents per week threshold that differentiates substantial and moderate risk.

According to the CDC, vaccination rates continue to increase, albeit more slowly; 43% of Arizona’s adult population is fully vaccinated and another 12% have received one dose. With only 68% of its ≥65 population fully vaccinated, Arizona ranks 42nd among the 50 states. The 400,000 or so unvaccinated or partially vaccinated Arizonans >65 years of age will remain at risk of developing severe COVID-19 disease and death through the summer months given that many Arizonans <65 years of age remain unvaccinated.

Note: Data for this report was updated Friday, May 21 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.

Test positivity among those undergoing traditional nasopharyngeal PCR testing has plateaued at 10%. It remains (barely) within the 5 – 10% window for optimal public health practice (Figure 3).

As of May 20th, 581 (8%) of Arizona’s 8607 general ward beds were occupied by Covid-19 patients, a 2% decrease from the previous week’s 594 occupied beds (Figure 4 and Figure 5 Panel A). Another 1004 (12%) beds remained available for use. The number of available beds is higher than the previous week’s 977 beds.

The summer-fall nadir was 468 occupied beds on September 27th. The post-holiday nadir was 516 beds on April 4.

As of May 20th, 167 (11%) of Arizona’s 1746 ICU beds were occupied with Covid-19 patients, a 13% decrease from the prior week’s count of 193 patients (Figure 4 and Figure 5 Panel B). An additional 269 (15%) ICU beds remained available for use. This is similar to the prior week’s 259 available beds. The summer-fall nadir was 114 occupied beds on September 22^nd. The post-holiday nadir was 140 beds on April 7th.

Arizona hospital occupancy remains above seasonal levels. Improvements in ward and ICU occupancy have stalled at ≥85% occupancy (Figure 6). This indicates that medically necessary procedures that were previously postponed are being scheduled at higher than seasonal amounts to address the backlog of care. It will still take several more months to resolve. Occupancy will need to fall <70-75% before conditions will be back to “normal.” 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 May - June before returning to pre-outbreak levels.

The week ending January 17th remains Arizona’s deadliest with 1089 deaths (Figure 7). With 73 deaths recorded on March 28^th, it marks the first week with <100 Covid-19 deaths since October. Weekly deaths remain at or above the summer – fall nadir of 51 deaths per week (October 4^th) for several more weeks unless case rates meaningfully decline.

For the week ending May 16th, 400 Pima County residents were diagnosed with Covid-19 (Figure 8). This is an 11% decrease from the 449 cases initially reported last week.

New cases are being diagnosed at a rate of 38 cases per 100K residents per week, the lowest rate since May 28^th, 2020. October 9^th marked the summer - winter nadir at 46 cases per 100K residents per week and March 20^th marked the prior post-holiday nadir at 44 cases per 100K residents per week. Trends across the various age groups appear in Figure 9.