Headache as a COVID-19 onset symptom or Post-COVID symptom according to the SARS-CoV-2 Variant.

The presence of headache at the acute phase is a risk factor for post-COVID headache, whereas a history of primary headache does not appear to be associated with post-COVID headache. The prevalence of headache as an onset symptom appears to be variable for the different SARS-CoV-2 variants, but current data are inconclusive. However, the current evidence also suggests that headache represents a prevalent symptom in the acute and post-infection COVID-19 phase, regardless of SARS-CoV-2 variant.