#18,945
A week scarcely goes by without another study showing that COVID infection - and particularly, repeated infections - can have a major impact on a person's ongoing cardiovascular and neurological health.
While largely ignored by the public, a list of just some of the studies published in the last 3 months includes:
The Lancet: Vascular and Inflammatory Diseases after COVID-19 Infection and Vaccination in Children and Young People in England
JAHA: Viral Infections and Risk of Cardiovascular Disease: Systematic Review and Meta‐Analysis
Nature: Viral Infections and the Risk of Neurodegenerative Diseases (Meta-Analysis & Systemic Review)
European Society of Cardiology: Major Consensus Statement Released on Long-Term Cardiovascular Impact of COVID Infection
CSIRO Pub: Impacts of Long COVID on Disability, Function and Quality of Life for Adults Living in Australia
EHJ: Accelerated Vascular Ageing After COVID-19 Infection: The CARTESIAN Study
Preprint: Incidence of Long COVID Following Reinfection with COVID-19
COVID vaccines, while admittedly far from perfect, can help reduce (but not eliminate) the risks of infection, and even when breakthrough infections do occur; they can reduce the severity and/or duration of illness.
We've even seen studies showing vaccination may yield a marked reduction in the risk of developing Long COVID (see CIDRAP News 3 vaccine doses cut long-COVID risk by over 60%, analysis suggests).
This week, we've another preprint - this time from researchers at Johns Hopkins - which suggests that (pre-infection) COVID vaccination/boosters can reduce the severity of mental fatigue in recipients who were unlucky enough to go on to experience Long COVID.
Those who were both vaccinated & boosted saw a nearly 30% reduction in their WMFI (Wood Mental Fatigue Inventory) score.
This study is not without limitations and/or caveats. It is observational in nature, relies on self-reported data for infection and symptom history, and is based on a limited cohort (skewed towards those identifying as women, white, and from higher educational backgrounds).
Still, its findings align with others we've seen which find significant benefits from COVID vaccination and staying current with boosters.
I've posted the Abstract and a small excerpt below. Follow the link to read it in its entirety.
Pre-infection COVID-19 vaccination and long-COVID mental fatigue severity: Findings from the Johns Hopkins COVID Long Study
Madeline Sagona, Zhanmo Ni, Eryka Wentz, Karine Yenokyan, Thea Kammerling, Andrea DeVito, Priya Duggal, Shruti H. Mehta, Bryan Lau
doi: https://doi.org/10.1101/2025.11.07.25339684
This article is a preprint and has not been peer-reviewed [what does this mean?].
Preview PDF
Abstract
Background Long-COVID is a post-acute sequela of SARS-CoV-2 infection characterized by persistent, multi-system symptoms. Neurologic symptoms, such as mental fatigue, are often reported. While vaccination prior to infection is known to lessen symptom burden, its impact on mental fatigue remains unclear.
Objective Examine the association between vaccination and long-COVID-associated mental fatigue.
Methods We analyzed data from the Johns Hopkins COVID Long Study, a cohort study of 22,811 participants with and without infection. Among 2,634 participants with complete longitudinal follow-up, we examined the association between pre-infection vaccination and mental fatigue as measured by the Wood Mental Fatigue Inventory (WMFI; range 0-36, with lower scores indicating less fatigue). We considered three groups: long-COVID, recovered, and never infected, with the latter two groups as negative controls. We estimated the score differences between vaccinated and unvaccinated participants using covariate-adjusted quantile regression and mixed-effects linear models.
Results Among participants with long-COVID, receiving a booster dose was associated with lower WMFI scores across the distribution (1.5, 2.6, and 3.8 points lower at the 25th, 50th, and 75th percentiles; p ≤ 0.02) compared to those unvaccinated. Fully vaccinated participants also had lower scores, though these differences were not statistically significant. Findings were consistent in mixed-effect linear models where boosted (4.0 points lower) and fully vaccinated (1.9 points lower) participants with long-COVID had lower WMFI scores (p < 0.05). No associations were observed among recovered or never-infected participants.
Conclusion Pre-infection vaccination was associated with less long-COVID-associated mental fatigue, with the greatest benefit among boosted participants.
(SNIP)
Conclusion
In this nationwide virtual cohort, receiving a COVID-19 booster dose prior to SARS-CoV-2 infection was associated with lower long-COVID–associated mental fatigue. Fully vaccinated participants also hadlower WMFI scores compared to unvaccinated individuals, with smaller effects than those observed in boosted participants, consistent with a dose-response relationship. Associations were consistent across the distribution of scores and in mixed-effects models and were absent among recovered-COVID and never-infected controls, suggesting specificity to long-COVID.
As mental fatigue remains a common and disabling symptom of long-COVID, our results underscore the potential added value of vaccination in reducing long-term functional impairment. Future work should evaluate the biological and immunological mechanisms underlying this association, assess its durability over time, and determine whether additional booster doses further modify mental fatigue severity. Long-COVID remains a serious public health concern. Understanding how vaccination affects neurological symptoms like mental fatigue can inform future prevention strategies.
