The National Institute for Clinical Excellence (NICE) defines long COVID as “signs and symptoms that develop during or following an infection consistent with COVID-19, which continue for more than 12 weeks and are not explained by an alternative diagnosis”. 

When referring to long COVID: 

  • do not capitalise the word “long” unless at the start of a sentence 
  • always use upper case for the word “COVID” 
  • do not add the number “19” as you would when writing “COVID-19” 

Long COVID is sometimes referred to as post-COVID syndrome. For consistency, use long COVID.