The Lake County Health Department identified that lost in-person learning days detrimentally impacted the health and well-being of students and parents very early in the pandemic. The school closing, social distancing, and quarantine caused disruptions to daily routines that are essential to a child's welfare. The disruptions also caused many parents/guardians financial hardships. For children and adolescents with mental health needs, school closures also meant a lack of access to the educational and emotional resources obtained through schools. Declining test scores revealed the extent to which students in virtual” learning did not absorb learning. The Health Department was committed to find ways where children could stay in school for their overall health.
The target population affected by this problem is 5–18 years old students (122,352) and school staff (11,672) attending or working at K–12 schools in Lake County, Illinois. During the study period, the 90 Lake County schools that implemented TTS and reported cases to LCHD represented 53.7% (6,267) of staff members and 53.4% (65,384) of students in Lake County public/charter schools.* The 1,035 student close contacts participating in TTS had a median age of 10 years old (3-18 years old), 65.3% White, 6.9% Asian, 3.6% Black, and 23.5% other/unknown. More than half (60.5%) were non-Hispanic/Latino and 10.1 % Hispanic, and 29.4% other/unknown ethnicity.
At the time of the study, B.1.617.2 (Delta) variant was prominent and known to be highly aggressive and contagious, with high viral loads, more potential for severe illness among unvaccinated individuals, and possible existing substantial transmission in fully vaccinated people. The new Delta variant led to concerns in the community that schools were unsafe and sites of widespread COVID-19 transmission even with effective mitigation strategies in place. While schools had implemented universal masking, and physical distancing, improved hand hygiene and cleaning practices, and worked together with health departments on contact tracing, routine SARS-CoV-2 testing is not regularly implemented to provide added protection.
In the Spring of 2021, LCHD conducted a pilot project looking at limiting the quarantine of students with masked exposures to a COVID-19 case within 3 feet in a classroom setting (vs. the previous threshold of 6 feet). Even though the study period was short (2 weeks) and consisted of a small sample size, it showed that there was no secondary transmission in the classroom when mitigation was followed (unpublished). The layered mitigation schools had in place kept the spread of COVID-19 in the classroom low. Simply shortening the distance for the definition of a close contact helped more students stay in school, and benefit from more in-person learning days.
This pilot project facilitated the development of the TTS strategy in Lake County. While TTS addresses health inequities by providing students the opportunity to remain in school as an alternative to quarantine, low resourced schools struggled implementing TTS for a number of reasons. TTS requires many resources that some schools may not have available such as robust contact tracing and ample testing resources. The Health Department worked with superintendents early to link schools to free, state-funded COVID-19 testing programs (i.e., Shield) to ease the burden on school staff. Additionally, the Health Department developed a testing coordinator role, whereby the coordinator would assist schools in completing the necessary documentation and training. The Health Department also worked directly with the Illinois Department of Public Health (IDPH) to distribute rapid antigen kits (at no cost) to schools in need of testing resources. Finally, noting the disparity in the quality of TTS implementation, the Health Department offered a program where a contact tracer was embedded within a school district that needed help. Health Department school liaisons developed strong relationships with school nurses and superintendents to address any issues that arose immediately.
TTS is an effective alternative to quarantine that increases in-person learning days; but also, highlights the need to bring appropriate resources to schools. Many schools cannot currently shoulder the associated costs for such a resource-intensive strategy despite its many benefits. Currently, a small number of jurisdictions across the country have developed and implemented TTS. With its innovative approach, the Lake County Health Department was one of the earliest to implement TTS, starting on August 9, 2021. We collaborated with the CDC and the Illinois Department of Public Health (IDPH) to provide data to inform federal and state policies. Hosted by CDC, the Health Department also presented at two Community of Practice presentations to share its work. Additionally, the Health Department provided its TTS strategy protocols and supplementary documentation to health departments across the country looking to implement TTS. The Lake County Health Department was featured alongside other TTS implementors in a CNN piece on October 19, 2021, covering the ongoing CDC evaluation of TTS.
The Lake County Health Department developed its TTS strategy on evidence-based practices of multiple studies all showing that layered mitigation, including masking, led to low transmission of SARs-CoV2 in classrooms†§¶. And, as described in a Lancet article which showed the non-inferiority of daily testing and isolation**.
* Regional Office of Education Lake County, IL. School Directory-Enrollement (sic) 2021–2022.xlsx. Libertyville, IL: Regional Office of Education; 2021. https://e8c2718a-8f7f-4b7f-929b-1ecf15dd5e72.filesusr.com/ugd/a9e3eb_a559da92937a45d4871b397c2a805b97.pdf
† Hershow RB, Wu K, Lewis NM, et al. Low SARS-CoV-2 transmission in elementary schools—Salt Lake County, Utah, December 3, 2020–January 31, 2021. MMWR Morb Mortal Wkly Rep 2021;70:442–8. https://www.cdc.gov/mmwr/volumes/70/wr/mm7012e3.htm?s_cid=mm7012e3_w
§ Zimmerman KO, Akinboyo IC, Brookhart MA, et al. Incidence and secondary transmission of SARS-CoV-2 infections in schools. Pediatrics 2021. Epub March 1, 2021. https://doi.org/10.1542/peds.2020-048090external icon
¶ Falk A, Benda A, Falk P, Steffen S, Wallace Z, Hoeg TB. COVID-19 cases and transmission in 17 K–12 schools—Wood County, Wisconsin, August 31–November 29, 2020. MMWR Morb Mortal Wkly Rep 2021;70:136–40 https://doi.org/10.15585/mmwr.mm7004e3external icon
** Daily testing for contacts of individuals with SARS-CoV-2 infection and attendance and SARS-CoV-2 transmission in English secondary schools and colleges: an open-label, cluster-randomised trial. Lancet 2021;398:1217–29. https://doi.org/10.1016/S0140-6736(21)01908-5