Figure 2a shows quickening improvements among all groups. Worryingly, cases among those 65+ remain quite high despite high levels of vaccination among this group. Among school-age children, transmission is declining rapidly (Figure 2b). ASU, MCDPH, and PCHD researchers recently provided strong evidence supporting K – 12 mask mandates; Arizona schools without mandates had 3.5 times the odds of a school outbreak (95%CI 1.8 – 6.9) as compared to those with a mandate. The Arizona Supreme Court is expected hear oral arguments on the State’s prohibition of school mask mandates during the first week of November. A new, small, pre-Delta study of households with school employees or school children provides interesting data on well-defined transmission chains.

Comparing this year with last, overall community transmission remains higher this year, particularly among children (Figure 2c). Since mid-September, new case identifications on the UA COVID-19 Dashboard have declined briskly with only a small number of new daily cases being identified this past week.

Test positivity remains at 23% this week on a smaller base of clinical tests (Figure 3). Testing is inadequate for public health practice and many cases are going undiagnosed. It is unclear how much at-home testing is supplanting clinical testing. Even so, test positivity in the clinical setting remains an important barometer of transmission.

As of October 13th, 1769 (20%) of Arizona’s 8763 general ward beds were occupied by COVID-19 patients, a 0% increase from last week’s 1762 occupied beds (Figure 4 and Figure 5 Panel A). Another 674 (8%) beds remained available for use. The number of available ward beds is similar to last week’s 669 beds. Four-hundred seventy-one (471, 27%) of Arizona’s 1767 ICU beds were occupied by COVID-19 patients, a 1% decrease from last week’s 477 occupied beds (Figure 4 and Figure 5 Panel B). An additional 144 (8%) ICU beds remained available for use, slightly more than last week’s 126 beds. As a lagging indicator, hospital COVID-19 occupancy is now slowly declining, more so in the ICU than general ward.

While peak occupancy with this third wave never reached levels seen in the prior two, the base of the wave has the potential to be broader. For example, the summer 2020 and winter 2021 waves saw 57 and 98 days with combined ward and ICU occupancy >2000 patients, respectively. The current summer 2021 wave has so far seen 62 days with a combined occupancy >2000 patients. This persistent base of COVID-19 occupancy will have important implications for hospitals as they attempt to meet high season demands between October and February.

Arizona hospital occupancy remains far above seasonal levels. Safety margins, as measured by excess available beds, remain quite low (Figure 6). Because COVID-19 occupancy is improving slowly, hospitals should be prepared for >20% ward occupancy and >25% ICU occupancy for another week or two.

Arizona has been experiencing >200 COVID-19 deaths per week since August 22^nd. The week ending September 5th has now recorded 300 deaths (Figure 7). The week ending September 12th is close behind with 281 recorded deaths. So far, at least 20500 Arizonans have lost their lives to COVID-19.

For the week ending October 10th, 1761 Pima County residents were diagnosed with COVID-19 a 7% decrease from last week’s initial tally (Figure 8).

New cases are being diagnosed at a rate of 168 cases per 100K residents per week and this rate is decreasing by 16 cases per 100K residents per week. Trends across the various age groups appear in Figure 9.