The COVID-19 pandemic is well into its second year, but countries are only beginning to grapple with the lasting health crisis. In March, a UK consortium reported that 1 in 5 people who were hospitalized with the disease had a new disability after discharge1. A large US study found similar effects for both hospitalized and non-hospitalized people2. Among adults who were not hospitalized, 1 in 10 have ongoing symptoms 12 weeks after a positive test3. Treatment services for the long-term consequences of COVID-19 are already having to be absorbed into health and care systems urgently. Tackling this requires a much clearer picture of the burden of the disease than currently exists.