Accurate and timely data on COVID-19 are essential to understand the pandemic and guide policy decisions.1 Several countries openly release coherent and exhaustive daily updates of age-specific and sex-specific COVID-19 cases, deaths, hospitalisations and, more recently, vaccinations, whereas other countries still have trouble providing detailed and harmonised data.2

The pandemic is currently producing an extremely high incidence of cases due to the Omicron variant, especially in Europe. On Jan 11, 2022, the Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA, forecasted that more than 50% of the population in Europe would be infected with Omicron in the next 6–8 weeks.3 Despite this forecast, some European governments are considering treating COVID-19 as an endemic illness. This change would establish an epidemiological surveillance system similar to those used for primary-care sentinel influenza-like illnesses, prompting a substantial loss of follow-up in data collection of the usual daily indicators (eg, incident cases, hospitalisations, intensive care unit admissions, and deaths) and contact tracing. Moreover, breaking key time-trends in the current indicators would make evaluating future health policy interventions, analysing vaccination procedures, and comparing outcomes across countries and over time challenging.

Post COVID-19 condition, known as long COVID, has been well established to occur in people with SARS-CoV-2 infection. Long COVID usually occurs 3 months after the onset of COVID-19, with symptoms that last for at least 2 months that cannot be explained by an alternative diagnosis.4 A substantial number of people with COVID-19 have long COVID. WHO estimates that about 20% of people with COVID-19 have continuing symptoms 4–5 weeks after testing positive, and 10% have symptoms after 12 weeks.4 However, most studies focus on symptomatology, and surveillance of long COVID is not yet routine in European countries. Consequently, detailed population data is necessary to understand the prevalence and mechanisms of long COVID in different population groups, patients' needs in health and social services, and the economic consequences.

It is crucial to continue collecting daily data for the current morbidity, mortality, and vaccination indicators through the following stages of the pandemic, because treating COVID-19 as an endemic illness does not make it harmless.5 COVID-19 data should also be linked with national health and social registries to monitor the effect of current and potential new variants and the effect of long COVID on the population.

We declare no competing interests.