Long Covid Newsletter
Issue #10November 10, 20257 studies

Blood test detects long COVID brain fog with 90% accuracy by measuring key proteins

Blood test detects long COVID brain fog with 90% accuracy by measuring key proteins

Monday, November 10th Long Covid Newsletter Issue #10

This week's research brings us closer to real diagnostic tools for long COVID—and reveals some surprising patterns about who's most at risk.

🧬 Blood Test Achieves 90% Accuracy for Long COVID Brain Fog

Researchers analyzed over 7,000 proteins in blood samples from 48 long COVID patients with neurologic symptoms (brain fog, cognitive issues) compared to 44 control subjects. Here's what they found:

  • Three key proteins—C5a, TGF-β1, and Gliomedin—together identified neurologic long COVID with 94% sensitivity and 86% specificity (90% overall accuracy)

  • Adding three more biomarkers (Gal3ST1, IFN-λ1, and GHRH) boosted accuracy to 94%

  • A full panel of 11 biomarkers achieved nearly 100% accuracy, and importantly, many of these proteins can be targeted by existing FDA-approved drugs

Why this matters: This is the closest we've come to a reliable diagnostic test for one of long COVID's most debilitating symptoms. Brain fog affects millions but has been nearly impossible to diagnose objectively—until now.

Top 20% journal 🔗 Brain, Behavior, and Immunity - Health 🗓️ Oct 28

Key Findings

🧠 Mental Illness Increases Long COVID Risk by 10%

A massive study of 1,625,857 COVID patients found that those with serious mental illness (schizophrenia, bipolar disorder, or major depression) had 10% higher odds of developing long COVID. Among the 258,523 patients with mental illness, 24.8% developed long COVID compared to lower rates in those without psychiatric conditions.

💡 Mental health and physical health are more connected than we thought—psychiatric conditions may prime the body for post-viral complications.
🥈 Top 2% journal 🔗 JAMA Network Open 🗓️ Oct 29

🔬 Children's Antibody Levels Predict Long COVID Severity

In 92 children with long COVID, researchers found that anti-nucleocapsid antibody levels directly correlated with symptom severity. Kids with antibody levels above 11 had significantly worse symptoms, and these antibody levels also tracked with higher monocyte counts (immune cells linked to inflammation).

💡 A simple antibody test might help doctors predict which kids will struggle most with long COVID symptoms.
Top 20% journal 🔗 Journal of Infection and Public Health 🗓️ Oct 29

💊 Comprehensive Care Cuts Long COVID Costs to £1,700 Per Patient

UK researchers tracked 1,013 hospitalized COVID patients for 12 months and found that comprehensive follow-up services (assessment, rehabilitation, mental health support) cost only £1,700 per quality-adjusted life-year gained. Only 29% of patients felt fully recovered at one year, and 41% had new medical diagnoses.

💡 Investing in post-COVID care isn't just humane—it's economically smart at less than £2,000 per patient helped.
Top 20% journal 🔗 BMJ Open Respiratory Research 🗓️ Oct 31

🦠 Gut Bacteria Changes Persist in Long COVID

Multiple studies confirm that long COVID patients show consistent gut microbiome disruption: reduced beneficial bacteria like Faecalibacterium prausnitzii and Bifidobacterium, increased inflammatory species like Ruminococcus gnavus. These changes may fuel ongoing inflammation through the gut-brain and gut-lung connections.

💡 Your gut bacteria might hold keys to both understanding and treating long COVID's diverse symptoms.

🫀 Blood Clotting Problems Drive Long COVID Complications

A study of 32 long COVID patients found elevated levels of clotting proteins (prothrombin, thrombin, fibrinogen) and endothelial damage markers 26 months post-infection. Despite no detectable viral RNA, these patients showed persistent inflammation and coagulation abnormalities that create a pro-thrombotic (clot-forming) environment.

💡 Long COVID might be less about lingering virus and more about a blood system that can't reset after the initial infection.
🥉 Top 5% journal 🔗 Frontiers in Immunology 🗓️ Nov 3

🔥 Severe COVID Survivors Face 85% Mortality Rate

Among 59 long COVID patients who developed severe ARDS (acute respiratory distress syndrome), the mortality rate reached 85%. However, patients who received CPAP support initially had better survival rates (23%) compared to those treated with high-flow nasal cannula alone, though the numbers were small.

💡 The most severe long COVID cases remain extremely dangerous, but early respiratory support choices might matter for survival.
Top 20% journal 🔗 Journal of Clinical Medicine 🗓️ Oct 29

Implications

These studies paint a picture of long COVID as a complex, measurable condition with clear biomarkers and risk factors. The convergence on blood-based diagnostics, gut health, and targeted treatments suggests we're moving from 'it's all in your head' to 'here's exactly what's wrong and how we can help.'

Studies in this issue

Primary sources used for this newsletter.

  1. Blood markers linked to brain and nerve problems in long COVID
    main storyBrain, behavior, & immunity - health2025-10-28PMID 41146907
  2. Long-Term COVID-19 Symptoms in People with Schizophrenia, Bipolar Disorder, or Major Depression
    key findingJAMA network open2025-10-29PMID 41160025
  3. Levels of antibodies to COVID-19's core virus protein are linked to ongoing symptoms after infection in children
    key findingJournal of infection and public health2025-10-29PMID 41161027
  4. Breathing support methods and health outcomes in long COVID patients with severe lung failure
    key findingJournal of clinical medicine2025-10-29PMID 41156093
  5. The Gut Microbiome and Long COVID-19: What We Know So Far
    key findingInternational journal of molecular sciences2025-10-29PMID 41155411
  6. Clinical and cost-effectiveness of different care routes after COVID-19 hospital stays in the UK
    key findingBMJ open respiratory research2025-10-31PMID 41173504
  7. Immune and blood vessel problems linked to increased blood clot risk in Long COVID
    key findingFrontiers in immunology2025-11-03PMID 41181095

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