ABSTRACT
Background. In-person learning is important for children with intellectual and developmental disabilities (IDD) because of the additional health, vocational, and functional services for students at these schools. It may be difficult to reduce SARS-CoV-2 transmission in IDD schools because students require assistance with activities of daily living such as eating, during which social distancing and masking cannot occur. Surveillance testing and cluster tracking in schools for children with IDD, which may be considered high-risk environments for transmissions, could have benefits for mitigating transmission and keeping students in schools. The objective of this study was to identify SARS-CoV-2 clusters in IDD specific schools to compare viral transmission in delta and BA.1 variant waves. Methods. A saliva-based PCR test was offered to students and staff for weekly SARS-CoV-2 screening at six Special School District (SSD) schools dedicated to children with IDD. Clusters, which are considered 2 or more positives cases in the same classroom having an epidemiological link, were then recorded. All weekly testing took place between November 23, 2020 and May 27, 2022. Clusters were recorded from November 15, 2021 to January 28, 2022. A Fisher's exact test was used to compare categorical variables. Results. 545 (90%) and 113 (16%) students participated in weekly testing. 160 participants tested positive throughout the study, 23 (14%) during the delta variant wave and 115 (72%) during the BA.1 variant wave. There was no significant variation in age, race, ethnicity, gender, or vaccination status between positive cases recorded from alpha, delta, and BA.1 variant waves (Table 1). Notably, the vaccination rate of positive participants was lower than the vaccination rate of participants who did not test positive. 42 clusters were recorded, 3 (7%) during the delta variant wave and 39 (93%) during the BA.1 variant wave (Fig. 1). Conclusion. The highly transmissible BA.1 variant resulted in an increase in clusters observed in IDD specific schools. Mitigation strategies for less transmissible alpha and delta waves were not as effective in reducing transmission during the BA.1 wave.