Viral dynamics of the SARS-CoV-2 Omicron Variant in Paediatric Patients; A prospective cohort study.

BACKGROUND: There are limited data on the viral dynamics of SARS-CoV-2 in children. Understanding viral load changes over the course of illness and duration of viral shedding may provide insight into transmission dynamics to inform public health and infection control decisions. METHODS: We conducted a prospective cohort study of children 18 years and younger with PCR confirmed SARS-CoV-2 between February 1, 2022 and March 14, 2022. SARS-CoV-2 testing occurred on daily samples for 10 days; a subset of participants completed daily rapid antigen testing (RAT). Viral RNA trajectories were described in relation to symptom onset and resolution. The associations between both time since symptom onset/resolution and non-infectious viral load were evaluated using a Cox proportional hazards model. FINDINGS: Among 101 children aged 2 to 17 years, the median time to study-defined non-infectious viral load was 5 days post symptom onset, with 75% meeting this threshold by 7 days, and 90% by 10 days. On the day of and day after symptom resolution, 43 of 87 (49%) and 52 (60%) had met the non-infectious thresholds, respectively. Of the 50 participants completing RAT, positivity at symptom onset and on the day after symptom onset was 67% (16/24) and 75% (14/20). On the first day where the non-infectious threshold was met, 61% (n = 27/44) of participant RAT results were positive. INTERPRETATION: Children often met the study-defined non-infectiousness threshold on the day after symptom resolution. RAT tests were often negative early in the course of illness and should not be relied on to exclude infection. CLINICAL TRIALS REGISTRATION: NCT05240183.

Safety of administration of BNT162b2 mRNA (Pfizer-BioNTech) COVID-19 vaccine in youths and young adults with a history of acute lymphoblastic leukemia and allergy to PEG-asparaginase.

Vaccinationis a critical tool in the prevention of COVID-19 infection for individuals and for communities. The mRNA vaccines contain polyethylene glycol (PEG) as a stabilizer. Currently, in North America, only the BNT162b2 (Pfizer-BioNTech) mRNA vaccine is approved for individuals aged 12-17. Most patients treated with contemporary regimens for acute lymphoblastic leukemia receive PEG-asparaginase (PEG-ASNase) and 10%-30% will develop allergic reactions. Optimizing access and safety for vaccine administration for these patients is critical. This report describes a process developed to support COVID vaccination in a cohort of adolescents and young adults with a history of PEG-ASNase allergy.