ABSTRACT
Long covid follows 10-20% of first-time SARS-CoV-2 infections, but the societal burden of long covid and risk factors for the condition are not well-understood. Here, we report findings about self-reported sick leave and risk factors thereof from a hybrid survey and register study, which included 37,482 RT-PCR confirmed SARS-CoV-2 cases and 51,336 test-negative controls who were tested during the index and alpha waves. An additional 33 individuals per 1000 took substantial sick leave following acute infection compared to persons with no known history of infection, where substantial sick leave was defined as >1 month of sick leave within the period 1-9 months after the RT-PCR test date. Being female, [≥]50 years, and having certain pre-existing conditions such as fibromyalgia increased risks for taking substantial sick leave. Further research exploring this heterogeneity is urgently needed and may provide important evidence for more targeted preventative strategies.