{
  "schema_version": "2.0.0",
  "id": "cao-lormeau-zika-gbs",
  "name": "French Polynesia Zika–Guillain-Barré case-control study",
  "aliases": [
    "Cao-Lormeau Zika GBS study"
  ],
  "outbreak_event": "French Polynesia Zika outbreak 2013-14",
  "pathogen_id": "zika-virus",
  "pathogen_class": "virus",
  "exposure_ascertainment": "mixed",
  "design": "case_control",
  "denominator_defined": "no",
  "denominator_method": null,
  "recruitment_source": "hospital",
  "time_zero_definition": "Onset of Guillain-Barré syndrome (cases); preceding transient illness compatible with Zika ~6 days earlier",
  "time_zero_precision": "week",
  "control_group": "other_disease",
  "control_matching_variables": [
    "age",
    "sex",
    "island of residence"
  ],
  "n_source_population": null,
  "n_enrolled": 42,
  "n_analysed": 42,
  "followups": [],
  "max_followup_months": null,
  "instruments": [
    "brighton-gbs-criteria"
  ],
  "case_definition": "not_applicable",
  "pem_assessed": "no",
  "objective_measures": [
    "none"
  ],
  "specimens_collected": true,
  "specimen_types": [
    "serum"
  ],
  "acute_phase_specimens": "yes",
  "storage": null,
  "biobank_status": "unknown",
  "consent_future_use": "unknown",
  "external_access": "unknown",
  "contact": null,
  "registration_id": null,
  "funders": [
    "Labex IBEID",
    "European Union"
  ],
  "conflicts": null,
  "data_availability": null,
  "notes": "Case-control design (42 GBS cases; two control groups of 98 age/sex/island-matched patients and 70 Zika-positive patients without neurological signs). Establishes the causal link between Zika infection and an acute post-infectious immune sequela (GBS) rather than a chronic fatigue/pain syndrome; included to span the immune-neurological end of the PAIS spectrum. No longitudinal follow-up of chronic outcomes in this report.",
  "publications": [
    {
      "id": "cao-lormeau-2016",
      "title": "Guillain-Barré Syndrome outbreak associated with Zika virus infection in French Polynesia: a case-control study",
      "authors": "Cao-Lormeau VM, Blake A, Mons S, et al.",
      "year": 2016,
      "journal": "The Lancet",
      "doi": "10.1016/S0140-6736(16)00562-6",
      "pmid": "26948433",
      "url": "https://pubmed.ncbi.nlm.nih.gov/26948433/",
      "open_access": false,
      "is_primary_cohort_paper": true
    }
  ],
  "symptom_inventory_scope": "single_domain",
  "n_symptoms_queried": null,
  "symptom_instrument_note": null,
  "related_cohorts": [],
  "last_verified": "2026-07-20",
  "verified_by": "OSMF research-tracker (web-verified against source)",
  "harmonisation_ruleset": "pais-harmony-v1",
  "observations": [
    {
      "id": "zika-gbs-serology",
      "cohort_id": "cao-lormeau-zika-gbs",
      "publication_id": "cao-lormeau-2016",
      "schema_version": "2.0.0",
      "measure_id": "event:guillain-barre-syndrome",
      "measure_verbatim": "Guillain-Barré syndrome patients with serological evidence of recent Zika virus infection (anti-ZIKV IgM or IgG)",
      "population": {
        "scope": "whole_cohort",
        "stratum": null,
        "denominator_basis": "assessed_at_timepoint",
        "n_assessed": 42
      },
      "timing": {
        "timepoint_months": 0,
        "timepoint_band": "acute",
        "reference_period": "not_reported",
        "is_cumulative": false
      },
      "method": {
        "ascertainment": "unclear",
        "instrument_id": "brighton-gbs-criteria",
        "severity_threshold": null,
        "blinded_assessment": "not_reported"
      },
      "value": {
        "type": "proportion",
        "numerator": 41,
        "denominator": 42,
        "percent": 98,
        "ci": null,
        "precision": "exact"
      },
      "comparator": {
        "group": "none",
        "value": {
          "status": "not_applicable"
        },
        "effect": null
      },
      "harmonised": null,
      "provenance": {
        "source_locator": "Results (41/42 GBS cases had anti-ZIKV IgM or IgG)",
        "extracted_by": null,
        "extracted_on": null,
        "verified_by": "OSMF research-tracker (web-verified against source)",
        "verified_on": "2026-07-20",
        "extraction_method": "manual"
      }
    }
  ]
}