As the world continues to navigate the aftermath of the Covid-19 pandemic, a new challenge has emerged, affecting millions of people globally: long Covid. While the initial outbreak of Covid-19 claimed over a million lives in the United States and 7 million worldwide, the lingering effects of the virus have left an indelible mark on countless more. Long Covid, a term coined to describe a range of chronic and often debilitating conditions following Covid-19 infection, has become a major concern for both healthcare professionals and patients alike.
In the United States, survey data suggests that approximately 7% of adults and more than 1% of children—totaling between 15 to 20 million Americans—have experienced long Covid. Globally, this number exceeds 60 million. These statistics highlight the widespread impact of the condition, which has prompted urgent calls for a clearer understanding and better management of long Covid.
Given the diverse manifestations of long Covid, a variety of terms and definitions have emerged, none of which have gained unanimous acceptance from patients, clinicians, researchers, or government agencies. Recognizing the need for a standardized definition, the Administration for Strategic Preparedness and Response and the Office of the Assistant Secretary of Health tasked the National Academies of Sciences, Engineering, and Medicine (NASEM) with developing an improved definition that considers both patient needs and expert insights.
The resulting 2024 NASEM definition for long Covid represents a significant step forward in addressing this complex condition. The process of developing this definition was thorough and collaborative, involving committee members and lead staff who engaged deeply with the realities and severity of long Covid. Dr. Ely, one of the clinicians involved, initially approached the task with skepticism. Having spent 25 years working with critically ill patients and researching their recovery, he noticed similarities between the symptoms of long Covid and those of post-intensive care syndrome (PICS), a chronic condition affecting patients after severe illness.
However, this hypothesis did not hold up when similar symptoms began appearing in tens of thousands of patients from the first wave of the pandemic, many of whom had not been hospitalized and had only mild initial symptoms. This unexpected development highlighted the unique nature of long Covid and underscored the need for a distinct definition.
Patient advocacy groups played a crucial role in bringing attention to long Covid. Utilizing social media, these groups rapidly organized and contributed to the scientific discourse, helping to shape the understanding of the condition. Their efforts emphasized the importance of considering patient experiences in defining and addressing long Covid.
Long Covid patients join a broader community of individuals with chronic conditions linked to infections, such as myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), post-treatment Lyme disease, and multiple sclerosis. These conditions, which have historically been under-recognized, now benefit from the increased attention and research spurred by the Covid-19 pandemic.
The new NASEM definition for long Covid is more than just a semantic exercise; it offers legitimacy to those suffering and provides a framework for future clinical trials aimed at finding therapeutic solutions. By acknowledging the condition’s complexity and the necessity for a patient-centered approach, this definition paves the way for better treatment and care for those affected by long Covid.
Access the full report published in The New England Journal of Medicine here.