Purpose: Since the onset of the COVID-19 pandemic, most research has focused on the management of the acute symptoms
of the disease. Yet some people tend to experience symptoms beyond the acute phase, defined as Post-COVID-19 Condition
(PCC). This study aims to assess the impact of COVID-19 and PCC on anxiety and depression.

Methods: This is a prospective longitudinal cohort study among the Belgian adult population with recent SARS-CoV-2
infection for which contact tracing was initiated. A total of 3127 people were followed-up just after their infection and three
months later (from April 2021 to January 2022). Anxiety and depression were assessed at the two stages using the GAD-7
(Generalized Anxiety Disorder) and the PHQ-9 (Patient Health Questionnaire).

Results: Three months after infection, participants with PCC (50%) had an increased probability of having both anxiety and
depressive symptoms (p < 0.001). The proportion with anxiety and depressive symptoms at three months were significantly
higher in people with PCC (11% and 19%) compared to people without persistent COVID symptoms (3.8% and 4.2%) and
to a matched sub-sample not infected with SARS-CoV-2 (6.5% and 4.3%). Having at least one acute COVID-19 symptom
(p < 0.001), experiencing financial loss following the infection (p < 0.001), and different PCC symptoms were associated
with anxiety and depressive symptoms worsening over time.

Conclusions: This study showed that three months after a SARS-CoV-2 infection, one in two people suffer from PCC with
significant consequences for their mental health. Follow-up on mental health must therefore have an important place in
people suffering from PCC.