Inclusion Criteria:  Common to cases and controls:  Age ≥ 18 years old and <60 years old Good oral and written command of French Level of education ≥ 7 years of schooling Initial episode of COVID-19 within 2 to 12 months Symptomatic initial episode of COVID-19 Initial symptoms not explained by another diagnosis Initial episode documented by RT-PCR positive for SARS-CoV-2 and / or positive antigen test and / or positive serology (in the absence of vaccination) Express consent to participate in the study Affiliate or beneficiary of a social security scheme  Case group:  Presence of at least one of the initial symptoms beyond 4 weeks following the onset of the acute phase of the disease Prolonged symptoms not explained by another diagnosis with no known link to COVID-19 Neurocognitive complaint (s) previously objectified by a neurologist and after completion of a neuro-psychological assessment Impact of neurocognitive disorders on daily life authenticated by a Glasgow outcome scale extended ≤ 7 (see appendix 1) Evolution of complaints for 2 to 12 months compared to the date of their first appearance  Exclusion Criteria:  Exclusion criteria common to cases and controls:  Person benefiting from a legal protection measure Pregnant or breastfeeding woman  At least one neurological pathology among:  encephalopathy encephalitis severe neurological form of the initial episode of COVID-19 neurodegenerative disease History of stroke Serious psychiatric history Known nasal sinus pathology Hemostatic disorder Taking aspirin in the 15 days preceding the sample Treatment with anticoagulants Known allergy to lidocaine  Secondary exclusion criteria for controls:  - Positive SARS-CoV-2 RT-PCR on nasopharyngeal sample on the day of inclusion