The state of Arizona reported more than 10,000 new cases of COVID over the five days between Friday, July 30, and Tuesday, Aug. 3, leading to concern that the Delta variant is driving another wave of coronavirus cases in the state.
Dr. Joe Gerald, an epidemiologist with the UA Zuckerman School of Public Health who has been tracking the disease since it first appeared in Arizona in March 2020, sounded a somber warning with his weekly summary of trends.
"Unlike the summer of 2020 when we were headed into school re-opening with generally declining rates, the match has been lit and the kindling is aflame this time," Gerald wrote in an email. "For good measure, we are going to throw on some wet wood (children) in the coming weeks to ensure a robust bonfire for the Labor Day Marshmallow Roast."
While Pima County is averaging fewer cases per 100,000 people than the state as a whole, officials here are seeing an increase in school outbreaks as students return to the classroom, with health officials warning the spread of COVID in schools could have a significant impact on the community at large.
Pima County Health Department Director Dr. Theresa Cullen told the press last week that there had been eight outbreaks in schools and 56 school cases reported in the seven days following July 19, while there had been no outbreaks in the summer. She said they have closed one school classroom in the last five days and expected more cases to be reported on the horizon.
The cases are primarily from Vail School District, which resumed classes on July 19, and some of the outbreaks are in schools and others are from school related activities, like football, cheerleading or freshman orientations, Cullen said.
"We are now seeing this increase as students go back to school," said Cullen. "We anticipate that approximately 5% to 10% of the cases we are seeing right now will be due to school as opposed to a maximum of 4% last year."
Although several studies conducted early during the COVID-19 pandemic suggested children have lower incidence rates than adults, this may be partly due to children having fewer opportunities for exposure and a lower probability of being tested, CDC officials warned in an updated July 9 brief. They noted that studies that systematically tested children and adolescents, irrespective of symptoms, for COVID-19 infection or prior infection found "their rates of infection can be comparable, and in some settings higher, than in adults."
Cullen said pediatricians, primarily working in hospitals, "are seeing increased admissions and increased severity of illness, including ICU admission."
Currently, younger children are not eligible to receive the COVID-19 vaccine (only those 12 to 17 can receive the Pfizer vaccine), which are highly effective against hospitalization and death for all COVID-19 variants. In a late July briefing, ADHS Director Dr. Cara Christ (who recently announced she was leaving her job) reported that nearly 32% of 12 to 17 year olds have been vaccinated with at least one dose of vaccine.
The expected rise in school-related cases comes as the U.S. faces another wave of COVID-19 and the increased prevalence of the Delta variant.
As of July 30, Arizona has a high rate of transmission of 141 cases per 100,000 individuals per week, increasing by 32 cases per 100,000 residents per week In Arizona, according to Gerald's July 30 report. He said the Delta variant accounts for more than 75% of all cases.
Emerging data suggests lower effectiveness of the vaccine against confirmed infection and symptomatic disease caused by the Delta variant, according to the CDC's brief on vaccinations updated last Tuesday.
The CDC reports the Delta variant is "more than two times as transmissible as the original strains circulating at the start of the pandemic and is causing large, rapid increases in infections."
Pima County remains at a substantial rate of transmission of 69 cases per 100,000 individuals per week for the week of July 18, almost half the state's transmission rate. Cullen notes that until July 19, when the county received increased reports of school COVID-19 cases and outbreaks, the county was in moderate transmission.
"If we continue to see the increases that we have seen in the last week in our caseload, it is very possible that we will get to high transmission," said Cullen. "The reason why we don't separate out kids cases from adult cases, from elderly cases, and it's all one, is because the belief is that that reflects what's going on in the community at large. So, there is potential for a very significant impact on the community at large because of the school base cases."
Cullen said the health department is increasing their school team, because they believe "there will be an increasing number of outbreaks unless we have further mitigation."
However, new state law prohibits schools from mandating masks and requiring students and teachers get vaccinated. Schools in Arizona also faced backlash from Governor Doug Ducey's office for using language from the CDC, which states vaccinated individuals do not have to quarantine.
The Pima County Health Department is responsible for assessing vaccination status and determining the recommendation for isolation and quarantine, while school districts report positive cases, said Cullen.
"From the school district perspective, our goal is to say this is a Pima County Health Department prerogative, responsibility to keep the county safe and it falls within the purview of our authority to follow up on this," said Cullen. "We are cognizant of what the Governor has stated. We believe that our approach to this takes the onus off the school, and basically says the follow up is due to us."
Cullen emphasized that the county is "doing everything [they] can to keep kids in school."
The Pima County Health Department updated its Public Health Advisory to match the new CDC guidelines released last week. The CDC updated their guidance, recommending fully vaccinated individuals in areas with high or substantial rates of transmission should also wear a mask in public indoor settings because of the new evidence on the Delta variant.
Matching CDC language, they will be "strongly recommending all teachers, staff and students, visitors to K-12 schools wear masks indoors, regardless of vaccination status." Cullen hopes school superintendents will elect to push out the same recommendation and language.
Catalina Foothills School District and Tucson Unified School have opted to post signage around schools to encourage masking and the Catalina Foothills School District has updated their mitigation plan to match the new CDC guidelines.
According to a statement from TUSD, "The Tucson Unified School District Administration strongly recommends universal mask wearing for all students and staff. Per House Bill 2898, we are unable to mandate mask wearing. TUSD supports Superintendent of Public Instruction Kathy Hoffman's recommendation to have all students and staff wear masks when on school campuses."
In an email sent to families and staff on Thursday, the Marana Unified School District indicated the administration "recommends face coverings while indoors regardless of vaccination status in accordance with CDC guidelines," but would also "remain optional in accordance with the Governor's Executive Order and House Bill 2898." Amphitheater school district will also follow Pima County and CDC guidelines.
In the updated July 9 brief on transmission in schools, the CDC notes that when a combination of effective mitigation strategies, like masking and social distancing, are implemented and "strictly adhered to in the K-12 in-person learning environment, the risk of transmission in the school setting appears to be lower than or equivalent to the transmission risk in other community settings."
"Schools have done an amazing job, they have all worked with us for the past months, over the last year to ensure that they have layered mitigation," said Cullen. "However, they have limited ability to do certain things and that's why we believe it is our responsibility to do the recommendation, the strong recommendation about masking."