New research highlights the complexity of Long COVID and why recovery often requires looking at the whole picture.

When people ask why Long COVID can be so difficult to understand, a new review published in Communications Medicine, by Mark Faghy and co-authors, offers part of the answer: Long COVID doesn't appear to be one thing. It appears to be many things happening at once.

The review summarizes evidence pointing to a wide range of changes in the body that may contribute to symptoms. These include changes in the immune system, nervous system, blood vessels, energy production, blood clotting, and in some cases, the possible persistence of viral material after the initial infection.

That complexity helps explain why symptoms can look so different from person to person. Fatigue, post-exertional symptom exacerbation (PEM), brain fog, poor sleep, dizziness, exercise intolerance, memory and concentration challenges, and nervous system symptoms may all arise from different combinations of underlying factors.

The researchers also highlight an important public health reality: Long COVID continues to affect millions of people worldwide, creating challenges not only for individuals and families, but also for healthcare systems, employers, and communities.

One of the strongest messages in the paper is that understanding Long COVID will require insights from many different fields. The authors point to the need for collaboration across areas such as immunology, neurology, cardiovascular medicine, rehabilitation, sleep medicine, mental health, and more. In the meantime, Pacing - getting the right mix of activity and rest - has helped people to tackle symptoms while supporting function. Also, interventions addressing the nervous system function and health should have positive impacts on both symptoms and how well other impacted body systems are working.     

At ThriveNinety, this resonates with what we've seen in practice. When symptoms involve multiple interconnected body systems, it makes sense to take a broader view of recovery too. While researchers continue working toward better diagnostics, there is growing recognition that supporting nervous system regulation, pacing, movement, sleep, recovery, and overall brain-body function can play an important role in helping people feel and function better. We have seen this working in practice, and as more research is published, it has shed light on the mechanisms behind why a recovery approach that supports multiple body -systems is so impactful.  

The science is still evolving. But one message is becoming increasingly clear with each new study: Long COVID is complex, and fully understanding it will require looking at how multiple body systems interact and influence one another, rather than focusing on any single explanation. 

Read the full research paper: Current Status and Future Directions in Long COVID Pathophysiology (Communications Medicine, 2026). Current status and future perspectives on the mechanistic and pathophysiological understanding of long COVID 

Warmly,
Katie & Andrea

PS: Research shows Long COVID is complex, involving multiple body systems. Understanding – and supporting – those systems together may be one of the keys to improving symptoms and restoring function.