On Wednesday morning, Pima County Health Director Dr. Theresa Cullen held a press conference addressing recently updated Centers for Disease Control and Prevention mask-wearing guidelines for vaccinated individuals in light of the spread of the COVID-19 Delta variant in the community. The CDC updated their recommendation on Tuesday, July 27, citing new evidence suggesting that the vaccinated population can contribute to the transmission of the Delta variant.

Cullen began by summarizing the reasons behind the national decision from the CDC. She then transitioned to address the situation in the county. According to Cullen, Pima County is experiencing a rise in cases at 65 per 100,000. This rate was classified as “substantial” by the CDC on July 19. 

Cullen also drew attention to increased hospital bed utilization while noting that this rise is not solely due to COVID-19 cases but also due to other diseases. The spread of the Delta variant is on the rise in Pima County, with cases increasing from one case on June 12 to 41 cases on July 17, as collected by random sequencing, according to Cullen. 

“Now remember, this is random sequencing. Approximately 12% of cases are being sequenced, so it is not an overall [measurement], and it is random,” Cullen said in reference to the 41 cases associated with the Delta variant this month. “It has a very large confidence interval, which means it could be double that number.” 

A key point of concern Cullen discussed was the increase in the number and severity of cases among the K-12 age group. 

“We are seeing an increase in pediatric COVID-19 associated ER visits, admissions, including ICU admissions,” Cullen said. 

As schools prepare to return for the fall, cases associated with school gatherings such as orientation and extracurricular activities have risen. Cullen reported 56 school-related cases in the last seven days, with eight outbreaks occurring on the day of the conference. An outbreak is defined as two cases within 14 days that are linked within a school. Because of this rise, Cullen urged parents, teachers and students to wear masks when in indoor school settings.

“We anticipate that approximately 5-10% of the cases we are seeing right now will be due to school as opposed to a maximum of 4% last year,” Cullen said.

Cullen also noted that the increase in cases was not seen in daycares, thus, current county health department recommendations for masking exclude 2- through 5-year-olds.

During the question and answer portion of the conference, representatives from the local press raised concerns about schools’ limited ability to mitigate the spread of COVID-19. Last month, Arizona Gov. Doug Ducey signed an Arizona budget preventing public schools from enforcing mask mandates. In response to the new CDC guidelines, Ducey maintained this stance. 

Cullen emphasized that there are currently no mandates in place, rather the Pima County Health Department strongly recommends compliance with updated masking guidelines. She also indicated that the county recently expanded its school-based team and will continue using a reporting line as well as tracing methods to respond to potential increases in school outbreaks as fall approaches. Cullen emphasized that the county, not the school, declares an outbreak.

“We are cognizant of what the governor has stated,” Cullen said. “We believe that our approach to this takes the onus off the school, and basically says the follow-up is due to us [the county].”

According to the Arizona Department of Health Services COVID-19 dashboard, 48.4% of Pima County’s eligible population has been vaccinated as of July 31. Cullen said that, while this is relatively high in comparison to other counties in Arizona, it is still “not where we need it to be.” She approximated breakthrough cases — COVID-19 cases contracted by fully vaccinated individuals — as a minimal 0.1%. Nonetheless, with the rising concerns of spreading the Delta variant, Cullen urged fully vaccinated individuals to wear masks indoors in compliance with new CDC guidelines. 

“We strongly recommend that all Pima County residents, including those fully vaccinated, wear masks in public indoor settings,” Cullen said.

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