Your gut bacteria during COVID infection may predict whether you develop long COVID

Key Findings

🏃 Exercise Quieted Brain Inflammation After Spike Protein Exposure — in Rats

• Rats exposed to the SARS-CoV-2 spike protein in the brain ran less and showed disrupted day-night activity patterns for 17 days — behavioral signatures that mirror long COVID fatigue.
• Rats that had access to running wheels before and after exposure did not develop the persistent hypothalamic inflammation seen in sedentary animals, and showed elevated brain corticosterone 18 days post-injection.

🫀 Long COVID Raises Cardiovascular, Kidney, and Lung Risk — and Age Changes the Picture

• A retrospective cohort study found that people with long COVID face elevated risks of adverse cardiovascular, renal, and pulmonary outcomes compared to those who recovered from COVID-19 without persistent symptoms.
• Risk profiles shifted meaningfully by age and sex, suggesting long COVID is not one uniform condition but a set of overlapping vulnerabilities that look different depending on who you are.

🧫 A Gut Protein May Be Driving Inflammation Across Multiple Diseases

• A study in Gut — one of the field's highest-ranked journals — identified intestinal flagellin, a bacterial protein, as a driver of multisystem inflammation through a specific immune signaling axis shared across rheumatoid arthritis, inflammatory bowel disease, and long COVID.
• Long COVID was used as a model precisely because its defined onset and treatment-naive status make gut-driven mechanisms easier to isolate.

🧠 Neurological Symptoms After COVID Hospitalization Persist — and Predict Cognitive Decline

• A 36-month longitudinal study of patients hospitalized for COVID-19 tracked neurological and psychiatric symptom trajectories and found persistent symptoms were associated with worse performance across specific cognitive domains.
• Baseline biological markers predicted who would have worse long-term neurological outcomes, pointing toward early biological signals that may flag high-risk patients.

😌 Higher Psychological Wellbeing Linked to Lower Long COVID Risk in Older Europeans

• Among nearly 30,000 adults aged 50 and older across 27 European countries and Israel, those with the highest psychological wellbeing scores were 23% less likely to develop long COVID than those with the lowest scores.
• The same group was also significantly more likely to get vaccinated — making it difficult to fully separate wellbeing's direct effect from its downstream behaviors.

🦠 Some COVID Antibodies May Help the Virus Enter Immune Cells — Others Block It

• Researchers identified four groups of antibodies targeting the SARS-CoV-2 receptor-binding domain that differ in how they regulate the virus's shape — and found that only some groups enabled the virus to enter macrophages, a process linked to severe inflammation.
• Critically, antibodies from other groups were able to inhibit that entry, suggesting vaccine design could potentially be tuned to avoid eliciting the problematic type.