COVID-19 affects the paediatric population less frequently than adults. A retrospective study was performed in a tertiary paediatric hospital in Mexico City in children <18 years of age who were hospitalized with a positive reverse transcription-polymerase chain reaction for SARS-CoV-2. Included in the study were 86 patients with a median age of 10 years old (IQR 2.6-14.3 years), who were classified in three groups: previously healthy, with chronic disease and immunosuppressed patients. The principal signs and symptoms were fever (81%), cough (51%) and headache (35%). A total of 20 patients (23%) required management in the paediatric intensive care unit (PICU) and 17% needed mechanical ventilation for an average of 12.7 days (IQR 2-29 days). There was no statistically significant difference between the three clinical classification groups in those patients admitted to the PICU, most of which were previously healthy patients. The mortality rate was 5% (four patients). Given that the paediatric population is susceptible to infection, potential transmitters and to clinical presentations with variable degrees of severity, it is important to continue reinforcing social distancing measures.