A recent study has uncovered unusual structures in the blood of individuals suffering from long Covid, which may be connected to debilitating symptoms such as brain fog and fatigue. Researchers have identified distinctive biomarkers that could provide insight into the underlying mechanisms of long Covid, a condition that has puzzled the medical community since the onset of the pandemic.
The study, published in the Journal of Medical Virology, was led by Professor Alain Thierry from Montpellier University and included contributions from South African physiologist Professor Resia Pretorius. The team analyzed blood samples from 50 long Covid patients and 38 healthy volunteers, revealing a significant increase in the presence and size of clots in the blood of those affected by long Covid.
Researchers discovered that these clots were nearly 20 times more prevalent compared to those in healthy individuals. They found that the clots contained neutrophil extracellular traps (NETs), sticky structures made up of DNA and enzymes that white blood cells release to ensnare invading viruses. Typically, NETs disintegrate after serving their purpose, but in long Covid patients, these structures became trapped within microclots, creating stubborn formations that can obstruct blood flow in small vessels.
The team utilized advanced imaging techniques, including imaging flow cytometry and fluorescence microscopy, to analyze blood samples. Their findings indicated that the NETs and microclots were present in all samples, but were notably more prominent in those with long Covid. The differentiation was so clear that when the samples were anonymized, an artificial intelligence system could correctly identify long Covid patients with approximately 91% accuracy.
This discovery suggests the potential for a biomarker that could aid clinicians in diagnosing long Covid, a condition often overlooked due to standard tests returning normal results. The relationship between the identified biomarkers supports two prevailing theories regarding the condition: one posits that microclots obstruct blood flow, while the other indicates that the sticky DNA webs created by NETs contribute similarly.
Research on this topic has evolved over time. In 2021, Pretorius’s team first highlighted the presence of microclots in long Covid patients. The following year, Thierry’s group reported heightened levels of NETs. The current study synthesizes these findings, proposing that the interaction between these two blood components may lead to complications associated with long Covid.
As scientists continue to unravel the complexities of long Covid, there is cautious optimism that understanding the role of these blood components could lead to effective treatments or even a cure. The implications of this research extend beyond individual health, impacting public health strategies as the world continues to navigate the long-term effects of the pandemic.
