Notes from the Field: Multipathogen Respiratory Virus Testing Among Primary and Secondary School Students and Staff Members in a Large Metropolitan School District — Missouri, November 2, 2022–April 19, 2023

Prospective Surveillance and Preliminary Results

To determine the prevalence of respiratory viruses in school students and staff members, prospective surveillance was implemented in a large metropolitan school district in Kansas City, Missouri with 33 pre-Kindergarten (pre-K)–grade 12 schools during the 2022–23 school year. All district students and staff members were eligible to enroll in opt-in respiratory virus testing and symptom surveys irrespective of the presence of symptoms; enrollment information was sent by the school district using existing communication channels. Self-collected anterior nasal swabs were obtained monthly and tested using multiplex viral polymerase chain reaction.* Thirty-six hours before each scheduled monthly test, an electronic survey was sent to enrolled participants (or their parent or guardian) inquiring about respiratory virus infection symptoms during the preceding 7 days.^† Logistic regression models were used to compare positivity across age groups. Regression models accounted for clustering within schools when calculating cluster-robust SEs. Percentile-based bootstrapped CIs were calculated using Stata 17 software (version 17.0; StataCorp). The goal of this report is to share timely virus testing results during ongoing surveillance. This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.^§

Among the 894 total participants, 639 (71.5%) were students (representing 3.0% of total district enrollment of 21,419), and 255 (28.5%) were staff members (representing 7.1% of the total 3,577 district full-time staff members). Demographic characteristics of participants were similar to those reported districtwide, except that the proportion of female participants was higher (60.7%) than that from districtwide estimates (51.1%), and the proportion of students qualifying for free or reduced price meals was lower (31.3% versus 38.0%)^¶ (3). Among students, the median age was 10.1 years (IQR = 7.5–12.5 years), 289 (45.2%) were male, 406 (63.5%) were non-Hispanic White (White), 80 (12.5%) were Hispanic or Latino (Hispanic), 49 (7.7%) were non-Hispanic multiracial (multiracial), and 46 (7.2%) were non-Hispanic Black or African American (Black). Among staff members, the median age was 42.2 years (IQR = 34.3–51.1 years), 21 (8.2%) were male, 214 (83.9%) were White, 12 (4.7%) were Hispanic, seven (2.7%) were multiracial, and five (2.0%) were Black.

A total of 3,232 surveillance specimens were tested, including 872 (27.0%) from staff members and 2,360 (73.0%) from students (Table). Student specimens included 90 (2.8%) from pre-K students, 1,413 (43.7%) from elementary school students, 479 (14.8%) from middle school students, and 378 (11.7%) from high school students. A median of four specimens per participant (IQR = 3–5) were collected; these included 80 (2.5%) in November, 404 (12.5%) in December, 711 (22.0%) in January, 798 (24.7%) in February, 824 (25.5%) in March, and 415 (12.83%) in April. Overall, 805 (24.9%) specimens tested positive for any virus (95% CI = 23.4%–26.4%). A substantially higher percentage of pre-K specimens tested positive (40.0%) compared with staff member specimens (14.1%) (p<0.001).** Overall, rhinovirus/enterovirus (RV/EV) was detected most frequently (392; 12.1%), followed by all seasonal coronaviruses including NL63, HKU1, OC43, and 229E (181; 5.6%). Among specimens from pre-K and elementary school students, RV/EV (14.4% and 17.1%, respectively), adenovirus (12.2% and 3.3%, respectively), seasonal coronaviruses (6.7% and 8.1%, respectively) and human metapneumovirus (4.4% and 3.7%, respectively) were frequently detected. Among staff member specimens, RV/EV (4.8%), seasonal coronaviruses (3.8%), and SARS-CoV-2 (3.3%) were frequently detected. Influenza and respiratory syncytial virus (RSV) were infrequently detected from surveillance specimens, possibly because testing commenced after the occurrence of early seasonal peaks (4,5). More than one virus was detected in 81 (2.5%) specimens.

Among the 3,232 symptom surveys sent, 2,393 (74.0%) were completed. Pre-K students had the highest prevalence of reporting one or more symptoms (41.1%) compared with high school students, among whom prevalence of symptoms was lowest (14.0%) (p<0.001).