The following is a curated review of key information and literature about this topic. It is not comprehensive of all data related to this subject.
Overview
Some patients experience new, recurring or ongoing symptoms related to COVID-19 several weeks after the acute phase of infection (Datta, November 2020; Greenhalgh, August 2020 Shah, January 2021). The U.S. Centers for Disease Control and Prevention recommends using the umbrella term “post-COVID conditions” for a wide range of signs and symptoms that occur four or more weeks after acute COVID-19 infection. In general, post-COVID conditions are characterized by a lack of return to a usual state of health following acute COVID-19 infection.
While standardized case definitions are still being developed, the World Health Organization has developed a working clinical case definition of post-COVID conditions:
“Post COVID-19 condition occurs in individuals with a history of probable or confirmed SARS-CoV-2 infection, usually 3 months from the onset of COVID-19 with symptoms that last for at least 2 months and cannot be explained by an alternative diagnosis. Common symptoms include fatigue, shortness of breath, cognitive dysfunction but also others which generally have an impact on everyday functioning. Symptoms may be new onset, following initial recovery from an acute COVID-19 episode, or persist from the initial illness. Symptoms may also fluctuate or relapse over time. A separate definition may be applicable for children.”
Post-COVID conditions are referred to by a wide range of names, including “long COVID,” “post-COVID syndrome,” “post-acute COVID-19 syndrome,” as well as the research term “post-acute sequelae of SARS-CoV-2 infection.”