Children have usually less severe illness due to COVID 19 as compared to adults but more chance of severe illness if they have develpomental or genetic anomalies.
According to one retrospective study in North America ,published inJAMA Pediatr,children having corona virus infections were divided into 4 categories
1.Mild: cough,sore throat,fever and myalgia
2.Moderate:cough,fever, sore throat and breathlessness and/or findings in chest radiograph consistent with SARS-Co-v2 pneumonia
3. Severe:cough,fever,sore throat,breathlessness with new requirement of oxygen or need of escalating the dose of oxygen if already being given with or without ventilator support
4.Critical: Children requiring mechanical ventilation,ARDS,shock,systemic inflammatory response syndrome,multiorgan failure.
A total of 48 children were included in study with a median age of 13 years. An average number of admission in PICU was, 3 admission per PICU. All children were diagnosed by examination of nasal swab.
About 50% children had one comorbidity,17% had 2 and 19% had 3 0r more comorbidities.
69% children were critically ill and 25% required vasoactive drugs.81% children required respiratory support and 38% children required mechanical ventilation.One child required ECMO.
Most common drug used was hydroxychloroquine.Other drugs being used were Azithromycin,Remdesivir,and Tocilizumab.
The overall case fatalities were 4.2%

REFERENCES:
Shekerdemian LS, Mahmood NR, Wolfe KK, et al; International COVID-19 PICU Collaborative. Characteristics and outcomes of children with coronavirus disease 2019 (COVID-19) infection admitted to US and Canadian pediatric intensive care units. [published online May 11, 2020]. JAMA Pediatr. doi:10.1001/jamapediatrics.2020.1948.