Viral persistence is one theory that may explain a subset of long covid and other postviral cases (mecfs example [1]). There's lots of theories including itacon

Viral persistence is one theory that may explain a subset of long covid and other postviral cases (mecfs example [1]). There's lots of theories including itaconate shunt [2] and metabolic trap [3], glutamate toxicity [4], cranio-cervical instability and infections causing breakdown of tendons [5], gut biome imbalances [6][7], endothelial damage, and others. I'm not sure what the most promising ones are but the search for biomarkers continues. What we call long covid or mecfs or chronic lyme or fibromyalgia etc etc are all umbrella terms for symptom clusters so they lack some specificity and are likely multi-causal. There are many overlaps in LC and mecfs patient populations in studies (vs controls), so its likely a fair-to-significant amount of LC is actually what we call mecfs. Much of the mystery and suffering of long covid would have been avoided if we'd invested anything in investigating these conditions pre-covid (mecfs has the least funding to disease burden and the worst quality of life of all major diseases), but the medical community generally didn't want to believe these diseases were real. Same thing happened with autoimmune conditions like lupus and MS before their mechanisms were discovered. All of these conditions predominately affect women. [1] https://me-pedia.org/wiki/Persistent_infection_hypothesis https://me-pedia.org/wiki/Persistent_infection_hypothesis [2] https://me-pedia.org/wiki/Itaconate_shunt_hypothesis https://me-pedia.org/wiki/Itaconate_shunt_hypothesis [3] https://me-pedia.org/wiki/Metabolic_trap https://me-pedia.org/wiki/Metabolic_trap [4] https://me-pedia.org/wiki/Glutamate https://me-pedia.org/wiki/Glutamate [5] https://me-pedia.org/wiki/Craniocervical_instability https://me-pedia.org/wiki/Craniocervical_instability [6] https://me-pedia.org/wiki/Microbiome https://me-pedia.org/wiki/Microbiome [7] https://www.remissionbiome.org/ https://www.remissionbiome.org/