Long Covid Newsletter
Issue #6October 13, 20257 studies

Long COVID reinfection doubles risk in kids, while treatment cuts risk by 12% in older adults

Long COVID reinfection doubles risk in kids, while treatment cuts risk by 12% in older adults

Monday, Monday, October 13th Long Covid Newsletter Issue #6

New research this week reveals surprising patterns about who's most at risk for long COVID—and what might actually help prevent it.

🚨 COVID Reinfection Doubles Long COVID Risk in Kids

A massive study of 465,717 children and teens found that getting COVID twice significantly increases their risk of developing long COVID symptoms. Here's what researchers discovered:

  • Kids who got reinfected had more than double the risk (2.08x higher) of receiving an official long COVID diagnosis compared to those with just one infection

  • The study tracked 24 different symptoms and conditions—reinfected kids showed increased risk for everything from heart problems and cognitive issues to fatigue and taste/smell changes

  • This pattern held true across all age groups from 12-21 years old, with particularly concerning increases in serious conditions like myocarditis and blood clots

Why this matters: Parents and doctors have been debating whether repeat COVID infections in kids are "no big deal"—this data suggests otherwise. With 58,417 children experiencing reinfections in just the study period, the cumulative health impact could be substantial.

🥇 Top 1% journal 🔗 The Lancet Infectious Diseases 🗓️ Oct 3

Key Findings

💊 Paxlovid Cuts Long COVID Risk—But Only for Older Adults

Analysis of 874,299 patients revealed that the COVID treatment nirmatrelvir-ritonavir (Paxlovid) reduces long COVID risk, but the protection varies dramatically by age. Adults 65+ saw a 12% risk reduction, while those 50-64 got 7% protection. However, the drug showed minimal benefit for adults 18-49 and zero effect for teens 12-17.

💡 Age matters for Paxlovid's long COVID benefits—older patients get the most protection.
🎖️ Top 10% journal 🔗 Open Forum Infectious Diseases 🗓️ Oct 1

🧠 Brain Scans Reveal Why Long COVID Causes Memory Problems

Scientists used advanced PET brain imaging on 30 long COVID patients with cognitive issues and found something striking: their brains showed increased AMPA receptors (key components for brain signaling) across large regions. This systemic increase may explain the "brain fog" many patients experience, as excessive excitatory signaling can disrupt normal information processing and potentially damage neurons over time.

💡 Long COVID brain fog has a measurable biological basis—it's not "all in your head."
🎖️ Top 10% journal 🔗 Brain Communications 🗓️ Oct 2

💗 Heart Rhythm Problems Linked to Spike Protein Inflammation

Researchers injected mice with just the SARS-CoV-2 spike protein (no live virus) and found it was enough to cause heart rhythm problems and structural changes to heart tissue. The spike protein triggered inflammation and disrupted key heart proteins responsible for electrical signaling, suggesting that viral pieces—not just active infection—can cause cardiac complications.

💡 COVID's heart effects may come from inflammatory responses to viral proteins, not just direct infection.
Top 20% journal 🔗 Scientific Reports 🗓️ Sep 30

🩸 Blood Clots Contain Immune System "Traps" in Long COVID

Scientists discovered that the abnormal blood clots found in long COVID patients aren't just random—they contain structures called neutrophil extracellular traps (NETs), which are normally used by immune cells to catch pathogens. These NETs appear to be stabilizing the microclots in circulation, potentially explaining why some long COVID patients have persistent circulation problems.

💡 Long COVID blood clots are reinforced by immune system components, making them more persistent.
Top 20% journal 🔗 Journal of Medical Virology 🗓️ Oct 2

🏃‍♀️ Exercise Helps Long COVID—But Dizziness is the Enemy

A study of 219 long COVID patients found that those maintaining moderate-to-high physical activity had better heart function, sleep quality, and overall wellbeing. However, dizziness was the strongest predictor of reduced activity—patients with more dizziness took fewer steps both on the same day and the following day, regardless of other symptoms.

💡 Managing dizziness might be key to helping long COVID patients stay active and recover better.
🎖️ Top 10% journal 🔗 BMC Public Health 🗓️ Oct 1

🧬 Depression and Anxiety Link to Autoimmune Activity

Among 228 long COVID patients in Colombia, 57% developed persistent symptoms, with high rates of depression (21%), anxiety (31%), and insomnia (29%). Importantly, these mental health symptoms correlated with the presence of autoantibodies—particularly antinuclear antibodies—suggesting that immune system dysfunction may directly contribute to psychiatric symptoms in long COVID.

💡 Long COVID's mental health effects may have an autoimmune component, not just psychological stress.
Top 20% journal 🔗 BMC Infectious Diseases 🗓️ Sep 30

Implications

This week's research paints a clearer picture of long COVID's biological mechanisms—from brain receptor changes to immune-stabilized blood clots—while revealing that prevention strategies work differently across age groups. The finding that reinfection doubles risk in children, combined with limited Paxlovid benefits for younger patients, suggests we need age-specific approaches to long COVID prevention and treatment.

Studies in this issue

Primary sources used for this newsletter.

  1. Long COVID linked to repeat COVID-19 infections in children and teens during the Omicron period
    main storyThe Lancet. Infectious diseases2025-10-03PMID 41043442
  2. Mental health symptoms linked to immune system problems in people with long COVID
    key findingBMC infectious diseases2025-09-30PMID 41023887
  3. Does Nirmatrelvir-Ritonavir Lower Post-COVID Risks in Young People and Adults?
    key findingOpen forum infectious diseases2025-10-01PMID 41031103
  4. Tiny blood clots linked to immune traps are higher in people with long COVID
    key findingJournal of medical virology2025-10-02PMID 41036702
  5. Inflammation from the COVID-19 spike protein may increase irregular heartbeats
    key findingScientific reports2025-09-30PMID 41028062
  6. Widespread rise in brain AMPA receptors linked to thinking problems in long COVID
    key findingBrain communications2025-10-02PMID 41036177
  7. Moderate to high physical activity linked to long COVID symptoms, heart recovery, fitness, sleep, and quality of life
    key findingBMC public health2025-10-01PMID 41029289

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