TABLE 1.
Demographics, Policies Used by Districts, Vaccination Rates, and Community Transmission
| All Districts n = 61 (%) | Universal Masking Policya n = 46 (%) | Partial Masking Policies n = 9 (%) | Optional Masking Policy n = 6 (%) | |
|---|---|---|---|---|
| Students in-person | 1 112 899 | 1 075 982 | 32 967 | 3950 |
| Staff in-person | 157 069 | 151 149 | 5294 | 626 |
| District sizeb | ||||
| 0–4999 | 34 (56) | 23 (50) | 5 (56) | 6 (100) |
| 5000–20 000 | 16 (26) | 12 (26) | 4 (44) | 0 (0) |
| >20 000 | 11 (18) | 11 (24) | 0 (0) | 0 (0) |
| Initial quarantine policyc | ||||
| CDC guidance | 21 (34) | 17 (38) | 1 (11) | 3 (50) |
| Unmasked and unvaccinated close contacts quarantine | 32 (52) | 24 (53) | 6 (67) | 2 (33) |
| None | 1 (2) | 0 (0) | 0 (0) | 1 (17) |
| Other | 3 (5) | 1 (2) | 2 (2) | 0 (0) |
| Not reported | 4 (7) | 4 (9) | 0 (0) | 0 (0) |
| Lunch policyd | ||||
| Distancing and/or outdoor eating | 40 (66) | 31 (67) | 7 (78) | 2 (33) |
| No lunch policy | 21 (34) | 15 (33) | 2 (22) | 4 (67) |
| Vaccine required for eligible students | 1 (2) | 1 (2) | 0 (0) | 0 (0) |
| Vaccine required for eligible staff | 6 (10) | 6 (13) | 0 (0) | 0 (0) |
| Vaccination rates in surrounding countye | ||||
| Initiation of study (12–18 y), % | 36 | 41 | 23 | 20 |
| Termination of study (5–18 y), % | 38 | 42 | 25 | 23 |
| County community transmission, cases per 100 000 population per 7 df | ||||
| Initiation of study | 97 | 100 | 107 | 63 |
| Termination of study | 295 | 266 | 369 | 417 |
CDC, Centers for Disease Control and Prevention; COVID-19, coronavirus disease 2019; K–5, kindergarten through fifth grade.
“Partial” masking districts included: 4 districts that initially had optional masking and transitioned to masks required, 2 districts that transitioned between mask optional and required more than once during the study period, and 3 districts that had required and optional masking varying by either school grade level, or by community transmission threshold.
District size determined by number of students enrolled.
Initial quarantine policy was reported by the schools on the initial policy survey. “Unmasked and unvaccinated close contacts quarantine” category includes districts that required quarantine only if the exposed person was unmasked and unvaccinated. In the case that the exposed person was either masked during exposure or vaccinated, quarantine was in general not required. “Other” districts include 1 district that quarantined all K–5 classrooms if there was a positive case, but in grades 6 to 12, quarantine was only required for unmasked exposures; 1 district that required quarantine for any unvaccinated person within 3 feet or within 90 d of COVID-19 infection; and 1 district where quarantine depended on level of school.
“Distancing and/or outdoor eating” category included those districts who either ate indoors and implemented distancing or staggering of lunches or ate outdoors (with or without a distancing requirement).
Vaccination rates as reported by CDC vaccinations in the United States,15 by County dataset include percent of ages 12 to 18 y in the county containing the district with at least 1 vaccine at start of study (as of July 26, 2021); as authorization of COVID-19 vaccine for ages 5 to 11 y occurred during the study period, termination of study vaccination rates include percent of ages 5 to18 y with at least 1 vaccine in the county containing the districts (as of December 13, 2021).
Community transmission for each county corresponding to a district as reported by the CDC County Level of Community Transmission, including Historical Changes database,16 as cases per 100 000 population per 7 days. “Initiation of study” date was July 26, 2021 and “termination of study” date was December 13, 2021.