A new broadly inclusive definition of long COVID from the National Academies of Sciences, Engineering, and Medicine (NASEM) has been developed with the aim of improving consistency, documentation, and treatment for both adults and children.
According to the 2024 NASEM definition of long COVID issued on June 11, 2024, “Long COVID is an infection-associated chronic condition that occurs after SARS-CoV-2 infection and is present for at least 3 months as a continuous, relapsing and remitting, or progressive disease state that affects one or more organ systems.”
People with long COVID may present with one or more of a long list of symptoms, such as shortness of breath, rapid heartbeat, extreme fatigue, post-exertional malaise, or sleep disturbance and with single or multiple diagnosable conditions, including interstitial lung disease, arrhythmias, postural orthostatic tachycardia syndrome (POTS), myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), diabetes, or autoimmune disorders. The condition can exacerbate preexisting health conditions or present as new ones.
The definition does not require laboratory confirmation or other proof of initial infection. Long COVID can follow SARS-CoV-2 infection of any severity, including asymptomatic infections, whether or not they were initially recognized.
Several working definitions and terms for long COVID had previously been proposed, including those from the World Health Organization (WHO) and the US Centers for Disease Control and Prevention, but no common definition or terminology had been established.
The new definition was developed at the request of the Administration for Strategic Preparedness and Response and the Office of the Assistant Secretary for Health (OASH). It was written by a multi-stakeholder panel convened by NASEM, which recommended that the new definition be universally adopted by the federal government, clinical societies and associations, public health practitioners, clinicians, payers, the drug industry, and others using the term long COVID.
Recent surveys suggest that approximately 7% of Americans have experienced or are experiencing long COVID. “It’s millions of people,” panel chair Harvey V. Fineberg, MD, president of the Gordon and Betty Moore Foundation, told this news organization.
The new definition “does not erase the problem of clinical judgment ... But we think this definition has the real advantage of elevating to the clinician’s mind the real likelihood in the current environment of prevalence of this virus that a presenting patient’s strange symptoms are both real and maybe related as an expression of long COVID,” Dr. Fineberg noted.
One way this new definition differs from previous ones such as WHO’s, he said, is “they talk about a diagnosis of exclusion. One of the important points in our definition is that other diagnosable conditions like ME/CFS or POTS can be part of the picture of long COVID. They are not alternative. They are, in fact, an expression of long COVID.”
Indeed, the NASEM report also introduces the term infection-associated chronic condition (IACC). This was important, Dr. Fineberg said, “because it’s the larger family of conditions of which long COVID is a part. It emphasizes a relatedness of long COVID to other conditions that can follow from a variety of infections. We also adopted the term ‘disease state’ to convey the seriousness and reality of this condition in the lives of patients.”