{
  "schema_version": "2.0.0",
  "harmonisation_ruleset": "pais-harmony-v1",
  "id": "marburg-pacvs",
  "name": "PACVS registry cohort (Semmler/Mundorf)",
  "aliases": ["Post-Acute COVID-19 Vaccination Syndrome registry", "Marburg/Düsseldorf PACVS cohort"],
  "outbreak_event": "COVID-19 vaccination campaign (2021-)",
  "pathogen_id": "covid-19-vaccine",
  "pathogen_class": "vaccine",
  "exposure_ascertainment": "clinical_diagnosis",
  "design": "cross_sectional",
  "denominator_defined": "no",
  "denominator_method": null,
  "recruitment_source": "self_referral",
  "time_zero_definition": "First SARS-CoV-2 (mRNA) vaccination; chronic symptoms persisting >=5 months",
  "time_zero_precision": "month",
  "control_group": "healthy_convenience",
  "control_matching_variables": ["age", "sex"],
  "n_source_population": null,
  "n_enrolled": 191,
  "n_analysed": 191,
  "followups": [{ "months": 6, "n_assessed": 191, "n_lost": null }],
  "max_followup_months": 6,
  "instruments": [],
  "case_definition": "author_defined",
  "pem_assessed": "no",
  "objective_measures": ["lab_panel"],
  "specimens_collected": true,
  "specimen_types": ["serum"],
  "acute_phase_specimens": "no",
  "storage": null,
  "biobank_status": "unknown",
  "consent_future_use": "unknown",
  "external_access": "unknown",
  "contact": null,
  "registration_id": null,
  "funders": ["not reported"],
  "conflicts": null,
  "data_availability": null,
  "notes": "Comparative registry cohort of 191 people reporting post-acute COVID-19 vaccination syndrome (PACVS) vs 89 healthy controls, with serum biomarkers measured before and 6 months after vaccination. Distinguishes the vaccine trigger class (with Nohynek). Self-referred, not denominator-defined, so prevalence figures describe the affected registry, not a population; control-group values for individual markers were not extracted here and are marked measured_not_reported.",
  "symptom_inventory_scope": "targeted_panel",
  "n_symptoms_queried": null,
  "symptom_instrument_note": "Symptom clustering plus serum biomarker panel (interleukins, thyroid hormones, IgG subclasses, iron markers, neurofilament light chain, receptor autoantibodies).",
  "related_cohorts": [],
  "last_verified": "2026-07-20",
  "verified_by": "OSMF research-tracker (web-verified against source)",
  "publications": [
    {
      "id": "mundorf-2024",
      "title": "Clinical and Diagnostic Features of Post-Acute COVID-19 Vaccination Syndrome (PACVS)",
      "authors": "Mundorf AK, Semmler A, Heidecke H, et al.",
      "year": 2024,
      "journal": "Vaccines (Basel)",
      "doi": "10.3390/vaccines12070790",
      "pmid": "39066428",
      "url": "https://pubmed.ncbi.nlm.nih.gov/39066428/",
      "open_access": true,
      "is_primary_cohort_paper": true
    },
    {
      "id": "semmler-2023",
      "title": "Chronic Fatigue and Dysautonomia following COVID-19 Vaccination Is Distinguished from Normal Vaccination Response by Altered Blood Markers",
      "authors": "Semmler A, Mundorf AK, Kuechler AS, et al.",
      "year": 2023,
      "journal": "Vaccines (Basel)",
      "doi": "10.3390/vaccines11111642",
      "pmid": "38005974",
      "url": "https://pubmed.ncbi.nlm.nih.gov/38005974/",
      "open_access": true,
      "is_primary_cohort_paper": false
    }
  ],
  "observations": [
    {
      "id": "marburg-fatigue",
      "cohort_id": "marburg-pacvs",
      "publication_id": "mundorf-2024",
      "schema_version": "2.0.0",
      "measure_id": "sym:fatigue",
      "measure_verbatim": "malaise and chronic fatigue present in >80% of cases",
      "population": { "scope": "whole_cohort", "stratum": null, "denominator_basis": "assessed_at_timepoint", "n_assessed": 191 },
      "timing": { "timepoint_months": 6, "timepoint_band": "3-6mo", "reference_period": "current", "is_cumulative": false },
      "method": { "ascertainment": "structured_checklist", "instrument_id": null, "severity_threshold": null, "blinded_assessment": "not_reported" },
      "value": { "type": "proportion", "numerator": { "status": "measured_not_reported" }, "denominator": 191, "percent": 80, "ci": null, "precision": "approximate" },
      "comparator": { "group": "healthy_convenience", "value": { "status": "measured_not_reported" }, "effect": null },
      "harmonised": null,
      "provenance": { "source_locator": "Abstract (>80% malaise and chronic fatigue)", "extracted_by": null, "extracted_on": null, "verified_by": "OSMF research-tracker (web-verified against source)", "verified_on": "2026-07-20", "extraction_method": "manual" }
    },
    {
      "id": "marburg-il6",
      "cohort_id": "marburg-pacvs",
      "publication_id": "mundorf-2024",
      "schema_version": "2.0.0",
      "measure_id": "lab:il-6",
      "measure_verbatim": "elevated interleukin-6",
      "population": { "scope": "whole_cohort", "stratum": null, "denominator_basis": "assessed_at_timepoint", "n_assessed": 191 },
      "timing": { "timepoint_months": 6, "timepoint_band": "3-6mo", "reference_period": "current", "is_cumulative": false },
      "method": { "ascertainment": "lab_assay", "instrument_id": null, "severity_threshold": "above reference range", "blinded_assessment": "not_reported" },
      "value": { "type": "proportion", "numerator": { "status": "measured_not_reported" }, "denominator": 191, "percent": 60, "ci": null, "precision": "approximate" },
      "comparator": { "group": "healthy_convenience", "value": { "status": "measured_not_reported" }, "effect": null },
      "harmonised": null,
      "provenance": { "source_locator": "Results (elevated IL-6 in 60%)", "extracted_by": null, "extracted_on": null, "verified_by": "OSMF research-tracker (web-verified against source)", "verified_on": "2026-07-20", "extraction_method": "manual" }
    },
    {
      "id": "marburg-il8",
      "cohort_id": "marburg-pacvs",
      "publication_id": "mundorf-2024",
      "schema_version": "2.0.0",
      "measure_id": "lab:il-8",
      "measure_verbatim": "elevated interleukin-8 (reported 83-90%)",
      "population": { "scope": "whole_cohort", "stratum": null, "denominator_basis": "assessed_at_timepoint", "n_assessed": 191 },
      "timing": { "timepoint_months": 6, "timepoint_band": "3-6mo", "reference_period": "current", "is_cumulative": false },
      "method": { "ascertainment": "lab_assay", "instrument_id": null, "severity_threshold": "above reference range", "blinded_assessment": "not_reported" },
      "value": { "type": "proportion", "numerator": { "status": "measured_not_reported" }, "denominator": 191, "percent": 83, "ci": null, "precision": "approximate" },
      "comparator": { "group": "healthy_convenience", "value": { "status": "measured_not_reported" }, "effect": null },
      "harmonised": null,
      "provenance": { "source_locator": "Results (elevated IL-8, 83-90%)", "extracted_by": null, "extracted_on": null, "verified_by": "OSMF research-tracker (web-verified against source)", "verified_on": "2026-07-20", "extraction_method": "manual" }
    },
    {
      "id": "marburg-ft3",
      "cohort_id": "marburg-pacvs",
      "publication_id": "mundorf-2024",
      "schema_version": "2.0.0",
      "measure_id": "lab:ft3-low",
      "measure_verbatim": "reduced free tri-iodine thyroxine (>80%)",
      "population": { "scope": "whole_cohort", "stratum": null, "denominator_basis": "assessed_at_timepoint", "n_assessed": 191 },
      "timing": { "timepoint_months": 6, "timepoint_band": "3-6mo", "reference_period": "current", "is_cumulative": false },
      "method": { "ascertainment": "lab_assay", "instrument_id": null, "severity_threshold": "below reference range", "blinded_assessment": "not_reported" },
      "value": { "type": "proportion", "numerator": { "status": "measured_not_reported" }, "denominator": 191, "percent": 80, "ci": null, "precision": "approximate" },
      "comparator": { "group": "healthy_convenience", "value": { "status": "measured_not_reported" }, "effect": null },
      "harmonised": null,
      "provenance": { "source_locator": "Results (low fT3 in >80%)", "extracted_by": null, "extracted_on": null, "verified_by": "OSMF research-tracker (web-verified against source)", "verified_on": "2026-07-20", "extraction_method": "manual" }
    },
    {
      "id": "marburg-snfl",
      "cohort_id": "marburg-pacvs",
      "publication_id": "mundorf-2024",
      "schema_version": "2.0.0",
      "measure_id": "lab:snfl",
      "measure_verbatim": "elevated soluble neurofilament light chains above the 90th percentile",
      "population": { "scope": "whole_cohort", "stratum": null, "denominator_basis": "assessed_at_timepoint", "n_assessed": 191 },
      "timing": { "timepoint_months": 6, "timepoint_band": "3-6mo", "reference_period": "current", "is_cumulative": false },
      "method": { "ascertainment": "lab_assay", "instrument_id": null, "severity_threshold": ">90th percentile", "blinded_assessment": "not_reported" },
      "value": { "type": "proportion", "numerator": { "status": "measured_not_reported" }, "denominator": 191, "percent": 27, "ci": null, "precision": "exact" },
      "comparator": { "group": "healthy_convenience", "value": { "status": "measured_not_reported" }, "effect": null },
      "harmonised": null,
      "provenance": { "source_locator": "Results (sNfL >90th percentile in 27%)", "extracted_by": null, "extracted_on": null, "verified_by": "OSMF research-tracker (web-verified against source)", "verified_on": "2026-07-20", "extraction_method": "manual" }
    }
  ]
}