PACVS vs Gulf War Illness: symptoms, biomarkers, trials and research
A data-driven comparison of Post-Acute COVID-19 Vaccination Syndrome (PACVS) and Gulf War Illness built from the Open Source Medicine Foundation biomarker atlases, PubMed literature feeds, ClinicalTrials.gov registry extract and post-acute infection syndrome (PAIS) cohort database.
Both are exposure-attributed syndromes rather than infections: GWI to deployment-related chemicals and vaccines, PACVS to a vaccine. Autoimmune and autonomic markers appear in both literatures, which is the main reason to look at them side by side.
What each condition is
Post-Acute COVID-19 Vaccination Syndrome
Also known as: PCVS, Post-Vac Syndrome, Post-vaccination syndrome
PACVS (also written PCVS or post-vac syndrome) refers to persistent, Long COVID-like symptoms that begin shortly after SARS-CoV-2 vaccination and last for months in a small subset of recipients. It is not a recognised diagnostic entity in most countries and is defined differently across the handful of registry and survey cohorts that exist (Marburg, Yale LISTEN, VITAE). Research is early-stage: the literature is small, the biomarker evidence comes mainly from case series, and only a few interventional studies are registered.
Atlas scope: Molecular, serologic, immunologic, and functional alterations reported in Post-Acute COVID-19 Vaccination Syndrome (PACVS) — persistent symptoms following SARS-CoV-2 vaccination — from PACVS/PCVS primary studies and post-vaccination adverse-event literature.
OSMF resources: biomarker atlas · literature feed
Gulf War Illness
Also known as: GWI, Gulf War Syndrome, Chronic Multisymptom Illness
Gulf War Illness is a chronic multisymptom condition affecting roughly a quarter to a third of the nearly 700,000 US and allied personnel deployed in the 1990-1991 Gulf War. It is defined by the Kansas or CDC criteria (fatigue, pain, cognitive and mood symptoms, gastrointestinal and respiratory complaints) rather than by a single exposure, though pyridostigmine bromide, pesticides and low-level nerve agents are the leading hypotheses. Unlike the other conditions compared here it has no infectious trigger, which makes its biomarker overlap with post-viral syndromes scientifically interesting.
Atlas scope: Inflammatory, autoimmune, metabolic, cholinergic, and exposure-related biomarker alterations in Gulf War Illness (GWI / chronic multisymptom illness) compared to healthy deployed and non-deployed Gulf War veterans.
OSMF resources: biomarker atlas · literature feed
Side-by-side summary
| Measure | PACVS | Gulf War Illness |
|---|---|---|
| Biomarkers catalogued | 32 | 41 |
| Biomarker categories covered | autoimmune (8), functional (8), spike (4), molecular (4), metabolic (3), serologic (2), inflammatory (2), proteomic (1) | inflammatory (10), metabolic (8), exposure (7), autoimmune (5), neurological (4), functional (3), autonomic (2), ocular (2) |
| Markers with LOINC codes | 3 | 12 |
| Literature studies tracked | 15 | 75 |
| Most recent tracked study | 24 Sep 2026 | 25 Jun 2026 |
| Registered trials (all statuses) | 2 | 4 |
| Recruiting / not yet recruiting | 2 | 0 |
| Active, not recruiting | 0 | 0 |
| Completed | 0 | 4 |
| Terminated / withdrawn / suspended | 0 | 0 |
| Unknown status | 0 | 0 |
| Named cohorts in PAIS database | 4 | 0 |
| Therapeutic agents tracked | 7 | 10 |
Trial condition matching: PACVS uses keyword matching on registry condition and title fields; Gulf War Illness uses keyword matching on registry condition and title fields. Trials listing both conditions: 0.
Shared biomarkers (4)
Markers catalogued in both atlases, matched by normalised name or LOINC code. All shared markers are reported in the same direction in both atlases.
| Biomarker | Category | Direction in PACVS | Direction in Gulf War Illness | Matched by | Sources |
|---|---|---|---|---|---|
| IL-6 Interleukin-6 (IL-6) in Gulf War Illness | inflammatory | Increased vs HC | Increased vs HGV | LOINC 26881-5 | Mundorf et al. 2024; Johnson et al. 2016 |
| Heart rate variability (HRV) | functional / autonomic | Decreased vs HC | Decreased vs HGV | name | Mundorf et al. 2024; Gean et al. 2021 |
| Orthostatic heart rate increment | functional / autonomic | Increased vs HC | Increased vs HGV | name | Mundorf et al. 2024; Gean et al. 2021 |
| 6-minute walk distance | functional | Decreased vs HC | Decreased vs HGV | name | Halma 2024; Gean et al. 2021 |
Distinct biomarkers
Top 15 markers catalogued for one condition but not matched in the other. Full lists are on the PACVS atlas and the Gulf War Illness atlas.
Only in PACVS atlas (28)
- S1 in CD16+ monocytes Increased spike
- Circulating spike (post-mRNA myocarditis) Increased spike
- Spike in cutaneous lesions Increased spike
- Spike in neurological tissue Increased spike
- Anti-Spike (Anti-S) antibodies Increased serologic
- Anti-Nucleocapsid (Anti-N) antibodies Decreased serologic
- 2P proteotypic peptides (K986P/V987P) Increased molecular
- Wild-type viral spike peptides Decreased molecular
- BNT162b2 vaccine mRNA (qPCR) Mixed / conflicting molecular
- Vaccine mRNA (hybrid 3'UTR motifs) Mixed / conflicting molecular
- Anti-ACE2 autoantibodies Increased autoimmune
- Anti-AT1R (angiotensin II type 1 receptor) Increased autoimmune
- Anti-MAS1 receptor autoantibodies Increased autoimmune
- Anti-STAB1 autoantibodies Increased autoimmune
- Anti-ADRA2A (α2B adrenergic receptor) Decreased autoimmune
+13 more in the atlas.
Only in Gulf War Illness atlas (37)
- C-Reactive Protein (CRP) Increased inflammatory
- Tumor Necrosis Factor-α (TNF-α) Increased inflammatory
- Interleukin-1β (IL-1β) Increased inflammatory
- Interleukin-8 (IL-8 / CXCL8) Increased inflammatory
- Neopterin Increased inflammatory
- sCD26 (soluble DPPIV) Mixed / conflicting inflammatory
- sCD14 Increased inflammatory
- Homocysteine Increased metabolic
- Interferon-γ (IFN-γ) Increased inflammatory
- Glutathione (GSH) Decreased metabolic
- GSH:GSSG ratio Decreased metabolic
- 8-isoprostane Increased metabolic
- Coenzyme Q10 Decreased metabolic
- PON1 (paraoxonase 1) activity Decreased exposure
- PON1 Q192R polymorphism Mixed / conflicting exposure
+22 more in the atlas.
Overlapping therapeutics under investigation (0)
No therapeutic agent is currently tracked for both conditions. PACVS has 7 tracked agents and Gulf War Illness has 10; see the therapeutic agents index.
Research cohorts
PACVS cohorts (4)
- Post-Vac-Syndrom Deutschland patient survey survey, n=777, biobank not_applicable
- VITAE vaccine-injury survey (Halma & Varon) survey, n=706, biobank not_applicable
- Yale LISTEN post-vaccination syndrome cohort (Krumholz) survey, n=241, biobank active
- PACVS registry cohort (Semmler/Mundorf) cross sectional, n=191, biobank unknown
Gulf War Illness cohorts (0)
No named cohort for this condition in the PAIS database yet.
Recent research
Latest PACVS studies
Latest Gulf War Illness studies
Frequently asked questions
Can you have both PACVS and Gulf War Illness?
They are not mutually exclusive. Both are diagnosed clinically, and a person can meet criteria for PACVS and Gulf War Illness at the same time. In the OSMF data the two conditions share 4 catalogued biomarkers, 0 registered trials list both conditions, and 0 cohorts in the PAIS database are relevant to both. Overlap in a dataset is not evidence that one condition causes the other.
How do the biomarker profiles differ?
PACVS has 32 catalogued markers, led by autoimmune (8), functional (8), spike (4). Gulf War Illness has 41, led by inflammatory (10), metabolic (8), exposure (7). 4 markers appear in both atlases, and all shared markers are reported in the same direction. Categories unique to PACVS: molecular, proteomic, serologic, spike; unique to Gulf War Illness: autonomic, exposure, neurological, ocular.
Which has more active clinical trials?
PACVS has more: 2 active or recruiting trials versus 0 for Gulf War Illness (registry snapshot 07 Oct 2026). Totals including completed, terminated and unknown-status studies are 2 for PACVS and 4 for Gulf War Illness. Condition matching for PACVS, Gulf War Illness relies on keyword matching of registry condition fields and may miss trials. Trial counts measure research attention, not treatment efficacy.
Which condition has more recent research?
OSMF tracks 15 recent PubMed-indexed studies for PACVS (latest 24 Sep 2026) and 75 for Gulf War Illness (latest 25 Jun 2026). The feeds hold a rolling window of recent publications, so they indicate current publication pace rather than lifetime output. See the PACVS feed and the Gulf War Illness feed for the full lists.
Are the same treatments being studied for both?
No therapeutic agent is currently tracked for both PACVS and Gulf War Illness in the OSMF trial registry or agent database. That reflects the small or non-overlapping evidence base rather than proof that treatments differ.
Which has larger research cohorts?
The PAIS cohort database lists 4 named cohorts for PACVS and 0 named cohorts for Gulf War Illness, the largest being Post-Vac-Syndrom Deutschland patient survey (777 enrolled). Cohorts with stored biospecimens and open external access are the most useful for cross-condition biomarker validation.
Related comparisons
Cite this page
@misc{osmf_pacvs_vs_gulfwarillness,
author = {Open Source Medicine Foundation},
title = {PACVS vs Gulf War Illness: symptoms, biomarkers, trials and research compared},
year = {2026},
howpublished = {\url{https://research.opensourcemed.info/compare/pacvs-vs-gulf-war-illness.html}},
note = {Data as of 2026-10-07}
}Get OSMF research updates
New biomarker, trial and cohort data, summarised for patients and researchers.
Last updated 07 Oct 2026 (page build). Underlying data: literature feeds 07 Oct 2026 / 09 Jul 2026; trial registry 07 Oct 2026; atlases 30 Jun 2026 / 29 Jun 2026. Generated by scripts/build_compare_pages.py.