Evaluation of Test to Stay Strategy on Secondary and Tertiary Transmission of SARS-CoV-2 in K–12 Schools — Lake County, Illinois, August 9–October 29, 2021

Details

• Personal Author:
  Nemoto, Natsumi ; Dhillon, Soneet ; Fink, Steven ; Holman, Emily J. ; Cope, Amyanne Keswani ; Dinh, Thu-Ha ; Meadows, Juliana ; Taryal, Dina ; Akindileni, Funmilayo ; Franck, Megan ; Gelber, Emily ; Bacci, Lea ; Ahmed, Sana ; Thomas, Ebony S. ; Neatherlin, John C.
  More +
• Corporate Authors:
  CDC Foundation COVID-19 Corps. ; Chicago Medical School. ; Rosalind Franklin University. ; CDC COVID-19 Response Team. ; Lake County Health Department and Community Health Center (Waukegan, Illinois)
• Description:
  What is already known about this topic? COVID-19 Transmission within K–12 schools can remain low with implementation of multiple, concurrent Prevention strategies. ; What is added by this report? During fall 2021, 90 Lake County, Illinois, schools implemented Test to Stay (TTS), permitting eligible close contacts with masked COVID-19 exposures to remain in school. Secondary Transmission among TTS participants was 1.5%; no tertiary Transmission was observed among school-based contacts; however, tertiary cases were identified among household contacts. Implementation of TTS preserved up to 8,152 in-person learning days. ; What are the implications for public health practice? Although vaccination remains the leading recommendation to protect against COVID-19, TTS allows close contacts to remain in the classroom as an alternative to home quarantine. ; The COVID-19 pandemic has resulted in school closures and reduction of in-person learning (1). In August 2021, the Lake County Health Department (LCHD) in Illinois introduced a Test to Stay (TTS) strategy, whereby unvaccinated students, teachers, and staff members with certain school-related COVID-19 exposures could remain in school and participate in school-related extracurricular activities. Eligibility to participate in TTS required the following conditions to be met: 1) the exposure occurred while both the person with COVID-19 (index patient) and the close contact were masked; 2) the close contact remained asymptomatic, practiced consistent mask wearing, and maintained physical distancing; and 3) the close contact underwent tTesting for SARS-CoV-2 (the Virus that causes COVID-19) on days 1, 3, 5, and 7 after exposure to the index patient. LCHD permitted kindergarten through grade 12 (K–12) schools in Lake County to implement TTS; 90 schools, representing 31 school districts in Lake County, implemented TTS during August 9–October 29, 2021. During the implementation period, 258 COVID-19 cases were reported. Among 1,035 students and staff members enrolled in TTS, the secondary attack risk (number of close contacts who received a positive SARS-CoV-2 test result within 14 days after exposure to an index patient, divided by total number of close contacts) was 1.5% (16 of 1,035). Among the 16 secondary cases identified, all were in students, and none appeared to transmit SARS-CoV-2 to other school-based contacts. However, nine tertiary cases were identified among household contacts of the 16 secondary cases, and four of the nine were fully vaccinated. Assuming a maximum of 8 missed school days for every 10-day quarantine period, up to 8,152 in-person learning days were saved among TTS participants. Implementation of TTS with other concurrent Prevention strategies, including masking and physical distancing, limited further spread of SARS-CoV-2 within K–12 schools and allowed students to safely sustain in-person learning. Although vaccination remains the leading public health recommendation to protect against COVID-19 for those aged ≥5 years, schools might consider TTS as an option for allowing close contacts who are not fully vaccinated to remain in the classroom as an alternative to home quarantine. ; Suggested citation for this article: Nemoto N, Dhillon S, Fink S, et al. Evaluation of Test to Stay Strategy on Secondary and Tertiary Transmission of SARS-CoV-2 in K–12 Schools — Lake County, Illinois, August 9–October 29, 2021. MMWR Morb Mortal Wkly Rep. ePub: 17 December 2021. ; https://www.cdc.gov/mmwr/volumes/70/wr/mm705152e2.htm?s_cid=mm705152e2_w ; mm705152e2-H.pdf
• Subjects:
  • Adolescent
  • Adult
  • Aged
  • COVID-19
  • COVID-19 Testing
  • Child
  • Child, Preschool
  • Contact Tracing
  • CoronaVirus Infections
  • Female
  More +
• Source:
  MMWR: Morbidity and Mortality Weekly Report 2021; v. 70 Early Release
• Series:
  Weekly Report: Morbidity and Mortality Weekly Report (MMWR)
• ISSN:
  0149-2195 (print) ; 1545-861X (digital)
• Document Type:
  Journal Article
• Corporate as Subject:
  "Test to Stay"
• Place as Subject:
  Illinois
• Pages in Document:
  4 pdf pages
• Volume:
  70
• Download URL:
  https://stacks.cdc.gov/view/cdc/112763/cdc_112763_DS1.pdf
• File Type:
  [PDF - 231.92 KB]
• Collection(s):
  Morbidity and Mortality Weekly Report (MMWR)
• Main Document Checksum:
  urn:sha-512:b8c712064f9ca994e9826fffb4b4bfd0f2061a0617ec9277ed846c1d3e05587ab15977393002a17a2ea64157b696a497c54c90da921e433cb96f65cea167fdb4