SARS-CoV-2 transmission in a Georgia school district — United States, December 2020–January 2021

Gettings, Jenna R; Gold, Jeremy A W; Kimball, Anne; Forsberg, Kaitlin; Scott, Colleen; Uehara, Anna; Tong, Suxiang; Hast, Marisa; Swanson, Megan R; Morris, Elana; Oraka, Emeka; Almendares, Olivia; Thomas, Ebony S; Mehari, Lemlem; McCloud, Jazmyn; Roberts, Gurleen; Crosby, Deanna; Balajee, Abirami; Burnett, Eleanor; Chancey, Rebecca J; Cook, Peter; Donadel, Morgane; Espinosa, Catherine; Evans, Mary E; Fleming-Dutra, Katherine E; Forero, Catalina; Kukielka, Esther A; Li, Yan; Marcet, Paula L; Mitruka, Kiren; Nakayama, Jasmine Y; Nakazawa, Yoshinori; O'Hegarty, Michelle; Pratt, Caroline; Rice, Marion E; Rodriguez Stewart, Roxana M; Sabogal, Raquel; Sanchez, Emanny; Velasco-Villa, Andres; Weng, Mark K; Zhang, Jing; Rivera, Grant; Parrott, Tonia; Franklin, Rachel; Memark, Janet; Drenzek, Cherie; Hall, Aron J; Kirking, Hannah L; Tate, Jacqueline E; Vallabhaneni, Snigdha

BACKGROUND: To inform prevention strategies, we assessed the extent of SARS-CoV-2 transmission and settings in which transmission occurred in a Georgia public school district. METHODS: During December 1, 2020–January 22, 2021, SARS-CoV-2–infected index cases and their close contacts in schools were identified by school and public health officials. For in-school contacts, we assessed symptoms and offered SARS-CoV-2 RT-PCR testing; performed epidemiologic investigations and whole-genome sequencing to identify in-school transmission; and calculated secondary attack rate (SAR) by school setting (e.g., sports, elementary school classroom), index case role (i.e., staff, student), and index case symptomatic status. RESULTS: We identified 86 index cases and 1,119 contacts, 688 (63.1%) of whom received testing. Fifty-nine (8.7%) of 679 contacts tested positive; 15 (17.4%) of 86 index cases resulted in ≥2 positive contacts. Among 55 persons testing positive with available symptom data, 31 (56.4%) were asymptomatic. Highest SAR were in indoor, high-contact sports settings (23.8%, 95% confidence interval [CI] 12.7, 33.3), staff meetings/lunches (18.2%, CI 4.5–31.8), and elementary school classrooms (9.5%, CI 6.5–12.5). SAR was higher for staff (13.1%, CI 9.0–17.2) versus student index cases (5.8%, CI 3.6–8.0) and for symptomatic (10.9%, CI 8.1–13.9) versus asymptomatic index cases (3.0%, CI 1.0–5.5). CONCLUSIONS: Indoor sports may pose a risk to the safe operation of in-person learning. Preventing infection in staff members, through measures that include COVID-19 vaccination, is critical to reducing in-school transmission. Because many positive contacts were asymptomatic, contact tracing should be paired with testing, regardless of symptoms.