Impact of the lockdown on the burden of COVID-19 in outpatient care in France, spring 2020.

BACKGROUND

To limit the spread of SARS-CoV-2 several countries implemented measures to reduce the number of contacts such as a national lockdown. We estimated the impact of the first lockdown on the burden of COVID-19 in the community in France.

METHODS

Physicians participating in the French Sentinelles network reported the number of patients with an acute respiratory infection (ARI) seen in consultation and performed nasopharyngeal swabs in a sample of these patients (first patient of the week). The swabs were tested by RT-PCR for the presence of SARS-CoV-2. Clinical and virological data were combined to estimate ARI incidence attributable to SARS-CoV-2 from 17 March to 10 May 2020.

RESULTS

The incidence of ARI attributable to COVID-19 decreased after the second week of the lockdown period from 142 (95%CI [101; 183]) to 41 (95%CI [21; 60]) per 100,000 population. A decrease was observed in all areas in metropolitan France. The youngest age groups (<15-years-old) were least affected with a cumulated incidence estimated to 14 per 100,000 population during the study period.

CONCLUSIONS

The data collected in primary care suggests that the first lockdown implemented in France during spring 2020 significantly reduced the incidence of acute respiratory infections including COVID-19 in France and limited the geographic spread of SARS-CoV-2.