This study is expected to provide, for the first time, data on Cov2-SARS circulation in asymptomatic children and children with moderate respiratory symptoms in order to construct the severity pyramid of this novel pathogen. This information will be essential in the coming weeks to understand the dynamics of the transmission of this pathogen at the population level and to highlight the relevance of public health interventions, particularly with regard to the systematic closure of schools and childcare facilities.

Cov2-SARS is an emerging respiratory virus of the coronavirus family responsible for a global epidemic since November 2019. As of March 10, 2020, it had caused more than 160,000 cases of corona virus disease (COVID-19), including more than 6,500 deaths worldwide. France is one of the main epidemic outbreaks with more than 5,000 confirmed cases and the number of diagnosed patients is increasing every day.

The number of confirmed paediatric cases is relatively low, and the mortality rate in children is close to zero. This contrast suggests that children are more likely to present pauci-symptomatic or even asymptomatic forms of the disease, which are therefore undiagnosed in most cases. Given the rapid spread of this virus, and the fact that indigenous cases without an obvious chain of transmission now appear to be frequent in France, it is possible that the pauci-symptomatic or asymptomatic child may play a role in the transmission of the pathogen and the dynamics of the epidemic, as documented for other respiratory pathogens such as influenza. Based on this hypothesis, the closure of children's communities has been organized in France and other highly endemic countries.

Inclusion Criteria:

• Asymptomatic children:
• Age between birth and 15 years
• Carrying out a visit within the framework defined by the learned societies and professional organisations representative of paediatrics in France, i.e. :
• The consultation of the first month and all consultations involving compulsory vaccinations (2, 4, 5, 11, 12, 16 months).
• Consultations for acute pathologies, infectious or not.
• Monitoring of chronic diseases that warrant clinical examination (the majority of which can be carried out by telemedicine) or in the case of acute exacerbation.
• In one of the participating outpatient centres
• During the study period
• With a clinical examination that does not reveal any progressive infectious pathology

AND Pauci-symptomatic children

• Age between birth and 15 years,
• Consultant at one of the participating outpatient centres
• During the study period
• And presenting with a mild respiratory infection:
• Rhinopharyngitis, Acute otitis media, Angina, Bronchitis, etc.
• Acceptance to participate in the protocol by one of the holders of parental authority
• Affiliated to a social security

Exclusion Criteria:

• Refusal to participate in the study