Scientists studying the long-term effects of COVID-19 may have finally found an explanation for the long-lasting effects like brain fog and exhaustion that we’ve come to call long COVID.

A new study published in the Journal of Medical Virology suggests the problem may lie in tiny blood clots called microclots and a sticky molecular web spun by immune cells known as neutrophil extracellular traps, or NETs.

Microclots are a smaller, sneakier version of a blood clot and apparently far more persistent in people with long COVID. First flagged by South African physiologist Resia Pretorius in 2021, microclots can clog capillaries just enough to slow blood flow and starve tissues of oxygen, exactly the kind of thing that could help fuel debilitating fatigue.

Separately, French geneticist Alain

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