More than five years into the pandemic, Long Covid remains without a proven treatment, primarily due to a lack of consensus on its causes. While most research focuses on physiological mechanisms, a minority of researchers, particularly in France, continue to explore psychological factors—a stance that has angered patient advocacy groups.
Patient Frustration Boils Over
“In 2026, it is unacceptable to psychologize this,” fumes Ryan, a young man who has lived with Long Covid for four years. He was among a dozen patients protesting outside Paris’s iconic Hôtel-Dieu hospital, expressing deep frustration with the medical establishment.
Long Covid, characterized by persistent symptoms like fatigue, respiratory issues, and muscle pain long after the initial infection, affects a significant portion of survivors. The World Health Organization estimates that 6% of Covid patients develop prolonged symptoms, though definitions vary.
Associations like France’s Winslow Santé publique, which organized the protest, criticize the lack of recognition from health institutions and the absence of clear therapeutic pathways from research.
The Search for a Cause
Despite the challenges, Long Covid has spurred unprecedented research into post-infectious syndromes. Leading physiological hypotheses include:
- Persistence of the SARS-CoV-2 virus in the body
- Chronic tissue inflammation
- Immune system dysregulation leading to autoimmunity
However, these avenues have not yet yielded effective treatments. “More than ten clinical therapeutic trials have been launched worldwide, but we are in total failure,” lamented Mireille Laforge, a CNRS researcher, at a recent press conference. She suggests the failure stems from not “targeting well,” positing that multiple types of Long Covid with different physiological processes may exist.
The Controversial Psychological Thesis
In this context, a dissenting school of thought has regained prominence. In a late-2025 op-ed in Le Monde, led by psychiatrist Cédric Lemogne, researchers called for a focus on a “science of symptoms” rather than solely identifying physiological causes.
The article provoked fierce opposition from patient groups and other scientists, who saw it as reviving the theory that Long Covid is primarily psychological. Lemogne’s profile is particularly contentious, as he is integral to a treatment pathway at Hôtel-Dieu that heavily incorporates psychotherapy.
“The triggering factor is often physical, but not necessarily the factors perpetuating the symptoms,” Lemogne told AFP. “Among these mechanisms, some are psychological, but that’s a term sometimes experienced as stigmatizing, so I could say cognitive or cerebral.” He cites a 2025 BMJ study showing modest benefits from psychotherapy and physical rehabilitation.
A Marginal View in Global Science
Despite Lemogne’s defense, the psychological thesis remains marginal in the broader scientific literature. Two major 2024 reviews in The Lancet and Nature Medicine focused exclusively on physiological pathways.
Epidemiologist Ziyad Al-Aly, author of the Nature Medicine review, clarifies the distinction: “Anxiety and psychological distress can be manifestations among others… But saying psychological disorders are a consequence of the illness is not at all like asserting they are the cause of the symptoms.”
He warns, “By conflating the two… we harm patients,” and notes the psychological hypothesis seems to find more “institutional” support in France than elsewhere.
The debate underscores the complex, unresolved nature of Long Covid, where the search for answers continues to collide with patient experiences and scientific disagreement.
