This is a summary, written by members of the CITF Secretariat, of:

Farrar DS, Drouin O, Moore Hepburn C, Baerg K, Chan K, Cyr C, Donner EJ, Embree JE, Farrell C, Forgie S, Giroux R, Kang KT, King M, Laffin Thibodeau M, Orkin J, OuldaliN, Papenburg J, Pound CM, Price VE, Proulx-Gauthier JP, Purewal R, Ricci C, Sadarangani M, Salvadori MI, Thibeault R, Top KA, Viel-Thériault I, Kakkar F, Morris SK. Risk factors for severe COVID-19 in hospitalized children in Canada: A national prospective study from March 2020–May 2021. medRxiv. .2022.04.06.22273409; doi:

The results and/or conclusions contained in the research do not necessarily reflect the views of all CITF members.

In this pre-print, not yet peer-reviewed, led by CITF-affiliated researchers CITF-affiliated researchers Dr. Shaun Morris from the University of Toronto and Dr. Fatima Kakkar of the Université de Montréal, along with Dr. Jesse Papenburg (McGill University), Dr. Manish Sadarangani (University of British Columbia), and Dr. Karina Top (Dalhousie University) and other investigators sought to identify factors associated with severe disease among hospitalized children with COVID-19 in Canada.

Among those children who were hospitalized, more than 40% had a chronic health condition. Examples of conditions associated with severe COVID-19 included those requiring medical equipment in daily life (e.g. presence of tracheostomy and/or requirements for home oxygen, intravenous feeding, or dialysis  and pulmonary conditions (e.g. bronchopulmonary dysplasia and uncontrolled asthma).

Key Findings

  • 544 children were reported hospitalized with SARS-CoV-2 infection from April 2020 to May 2021.
    • 7% with COVID-19-related symptomatic disease
    • 3% with incidental infection or infection control/social admissions.
  • Among the 330 hospitalizations for COVID-19 related symptoms, the median age was 1 year and 9 months and 43.0% had chronic comorbid conditions.
  • Severe disease occurred in 29.7% of COVID-19-related hospitalizations, most frequently among children aged 2-4 years (48.7%) and 12-17 years (41.3%).

The researchers concluded that severe COVID-19 related outcomes occurred in children of all ages. However, children with neurologic and pulmonary conditions as well as those who depend on daily access to medical equipment were at increased risk of severe COVID-19, demonstrating the vulnerability of these children. The authors suggest that their findings may be used to inform vaccination campaigns, to prioritize COVID-19 therapies and guide future decision-making.

The authors conducted a national prospective study on hospitalized children with lab-confirmed SARS-CoV-2 via the Canadian Paediatric Surveillance Program (CPSP). Data was gathered from April 2020–May 2021 with cases reported by a network of more than 2,800 paediatricians. The study team classified hospitalizations as COVID-19-related, incidental infection, or infection control/social admissions. Severe disease (among COVID-19-related hospitalizations only) was defined as disease requiring intensive care, technological support, select organ system complications, or death.