Zika fever
Enable an agent to recognise Zika fever, assess the evidence and course of a suspected episode, and identify appropriate testing, referral and transmission-prevention actions.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
recalled by Codex without web access - no source was read
Researched by: Codex
Purpose and description
Enable an agent to recognise Zika fever, assess the evidence and course of a suspected episode, and identify appropriate testing, referral and transmission-prevention actions.
Zika fever is an acute infectious disease caused by Zika virus, transmitted primarily by infected Aedes mosquitoes, that is often mild but can be associated with neurological complications and, when infection occurs during pregnancy, congenital abnormalities.
It can be Classify an episode against an identified clinical or surveillance definition and explain unmet criteria.; Identify missing exposure, symptom or specimen-timing evidence needed to assess Zika attribution.; Flag unresolved dengue or other competing diagnoses for clinical review.; Identify pregnancy-related or neurological findings requiring an applicable referral pathway.; Retrieve current jurisdiction-specific testing, management and transmission-prevention guidance.; Prepare an auditable surveillance summary with classification, uncertainty and reporting-rule provenance..
Distinguishing features
Distinguish Zika virus infection from Zika fever: infection frequently occurs without symptoms, so a positive infection result does not alone establish a symptomatic disease episode. [WHO Zika fact sheet](https://www.who.int/news-room/fact-sheets/detail/zika-virus)
Assess the combination of rash, fever, conjunctivitis and joint symptoms; neither the name 'fever' nor this symptom pattern establishes the cause without supporting evidence. [WHO Zika fact sheet](https://www.who.int/news-room/fact-sheets/detail/zika-virus)
Require an explicit dengue differential because compatible symptoms and exposure geography overlap. [CDC testing and diagnosis](https://www.cdc.gov/zika/hcp/diagnosis-testing/)
Separate molecular evidence from antibody evidence and retain whether dengue or other flavivirus testing resolves the attribution. [CDC dengue and Zika diagnostic guidance](https://www.cdc.gov/mmwr/volumes/68/rr/rr6801a1.htm)
Separate maternal disease from fetal or infant outcomes: pregnancy-associated infection can cause congenital harm, but maternal infection and congenital disease are distinct assertions. [WHO Zika fact sheet](https://www.who.int/news-room/fact-sheets/detail/zika-virus)
Scope
+ Zika-specific clinical manifestations, onset, course and outcomes
+ Exposure routes and evidence supporting attribution to Zika virus
+ Diagnostic evidence, differential diagnosis and versioned case classification
+ Pregnancy-related implications and links to congenital or neurological complications
+ Disease-specific management, prevention and surveillance decision requirements
- The Zika virus organism, genome and taxonomic classification
- Mosquito species biology and vector-control programme operations
- The patient's complete health record and individual care encounters
- Independent models of dengue, chikungunya and other differential diagnoses
- Full models of congenital Zika syndrome and Guillain-Barré syndrome
- Outbreak management, travel policy and population health programme administration
Characteristics
- Disease and infection classification
- Symptomatic disease; asymptomatic infection; exposure only; unresolved Prevents exposure or laboratory evidence from being treated automatically as Zika fever.
- Diagnostic certainty
- Suspected; probable; confirmed; excluded; indeterminate, as defined by the cited authority and revision Makes certainty dependent on a stated definition rather than an unqualified label.
- Clinical manifestation profile
- Presence, absence or unknown status for rash, measured fever, conjunctivitis, arthralgia and other documented manifestations Supports recognition while preserving missing observations and competing explanations.
- Episode timeline
- Dated exposure intervals, onset and resolution; elapsed days with uncertainty Connects exposure plausibility, specimen timing and observed course.
- Exposure route attribution
- Mosquito-associated; sexual; vertical; other documented route; unknown, each with evidence and certainty Supports route-specific investigation without treating a plausible route as proven.
- Laboratory evidence
- Links to assay, specimen, collection date, result, reporting laboratory and interpretation Allows diagnostic claims to be reassessed against the actual testing evidence.
- Pregnancy relationship
- Linked pregnancy, gestational age at possible infection, dating uncertainty and assessment date Identifies pregnancy-specific assessment needs without equating maternal and fetal outcomes.
- Course and complication status
- Active; resolving; resolved; persistent symptoms; complication under evaluation; unknown Distinguishes recovery from unresolved symptoms or a separate complication.
- Classification provenance
- Code system, edition, jurisdiction, code, label, mapping scope and source Prevents disease, infection and congenital-condition codes from being substituted without checking their meanings.
- Population occurrence estimate
- Count or rate with numerator, denominator, population, geography, observation period and ascertainment method Keeps symptomatic disease estimates distinct from reported infections and seroprevalence.
Where this came from
wikidata · CC0 1.0
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 13 layers · 21 findings · 38 questions.
Zika disease identity Establish what the registry entry denotes and how disease assertions relate to infection and classification systems.
The label Zika fever can otherwise collapse exposure, infection, symptomatic disease and congenital outcomes into one concept.
Infection and disease boundary
Separate the registered disease from infection status and the person experiencing it.
Symptomatic episode boundary
Record symptoms and attribution separately from infection evidence; keep asymptomatic infection linked without automatically treating it as a fever episode.
- Does the authoritative terminology used for this entry include asymptomatic infection, or only symptomatic Zika virus disease? boundary
- Which observed manifestations are attributed to this disease episode, and by whom? provenance
Versioned classification
Connect terminology mappings and case definitions to their intended uses.
Codes and case definitions
Record ICD and SNOMED mappings with editions and scope; distinguish surveillance classification from clinical diagnosis. CDC provides a specifically versioned 2024 surveillance definition. [CDC 2024 case definition](https://ndc.services.cdc.gov/case-definitions/zika-virus-disease-2024/)
- Which ICD-10 variant, ICD-11 release and SNOMED CT edition map exactly to this registry concept? definition
- Which issuing body, revision and jurisdiction govern the case classification, and is its purpose surveillance or clinical assessment? provenance
Zika exposure attribution Represent the route, place and timing evidence connecting an episode to possible Zika transmission.
Exposure interpretation must accommodate mosquito-associated and non-vector routes without inferring infection from travel alone.
Route evidence
Describe plausible transmission routes and the strength of their support.
Route-specific exposure
Keep each candidate route and its supporting observations separate from the final route attribution.
- What mosquito, sexual, pregnancy-related or other documented exposure could explain this infection? provenance
- What evidence distinguishes a documented transmission route from a possible one? boundary
Exposure time and place
Locate possible acquisition in time and geography using dated evidence.
Acquisition window
Preserve travel or residence intervals, other exposure dates and uncertainty about where infection was acquired.
- What exposure intervals precede symptom onset, and how precisely are those dates known? measurement
- Which dated public-health source describes Zika transmission at the relevant location during those intervals? provenance
Zika diagnostic evidence Connect clinical suspicion to appropriately interpreted laboratory evidence and competing diagnoses.
Symptoms overlap with other arboviral diseases, and test interpretation requires specimen and timing context.
Specimen and assay context
Make laboratory results interpretable against episode timing and the applicable testing algorithm.
Timed test interpretation
Retain molecular and serological results as distinct evidence, alongside specimen type, collection date and the interpretation supplied by the laboratory.
- Which assay and specimen produced each result, and how many days after onset or possible exposure was it collected? measurement
- Under the applicable testing guidance, what can this result establish or leave unresolved? definition
- Is further testing indicated by that guidance, and is it available through the relevant laboratory? action
Arboviral differential
Track alternative causes and ambiguity in Zika attribution.
Dengue and flavivirus ambiguity
Preserve dengue evaluation and unresolved serological attribution; positive antibody evidence may require additional interpretation or testing. [CDC dengue and Zika diagnostic guidance](https://www.cdc.gov/mmwr/volumes/68/rr/rr6801a1.htm)
- What evidence supports or weakens dengue, chikungunya or another explanation for this presentation? boundary
- What prior flavivirus infection or vaccination history is relevant to interpreting the antibody results? provenance
- What unresolved ambiguity must remain in the diagnostic assertion after available testing? definition
Zika course and consequences Represent the acute trajectory and clinically important pregnancy or neurological relationships.
An episode's apparent resolution does not by itself settle linked pregnancy outcomes or complication assessments.
Acute course
Describe manifestations and their progression without imposing a fixed course on every episode.
Manifestation trajectory
Record onset and resolution of individual manifestations, functional impact and persistent or atypical features.
- When did rash, fever, conjunctivitis, joint symptoms and other manifestations begin and resolve? measurement
- Which persistent or worsening findings require reassessment of the diagnosis or investigation of a complication? action
Pregnancy consequences
Link possible maternal infection timing to pregnancy assessment while keeping fetal outcomes separately evidenced.
Maternal and fetal separation
Maintain separate maternal infection, fetal assessment and infant outcome assertions, connected by an explicitly documented pregnancy relationship.
- Was a pregnancy ongoing during possible infection, and what gestational interval and dating uncertainty apply? measurement
- Which fetal or infant findings are observed, and which are only risks or pending assessments? boundary
- Which current pregnancy or infant evaluation pathway applies to the available evidence? action
Neurological consequences
Connect neurological presentations to assessment and separately modelled complications.
Neurological complication attribution
Zika infection is associated with Guillain-Barré syndrome and other neurological complications; an individual attribution requires its own evidence. [WHO Zika fact sheet](https://www.who.int/news-room/fact-sheets/detail/zika-virus)
- What new neurological manifestations have been documented, and when did they occur relative to the suspected infection? measurement
- What assessment supports a linked neurological diagnosis and its attribution to Zika? provenance
- Do the documented findings meet the applicable pathway's criteria for urgent evaluation? action
Zika actions and surveillance Connect evidence and disease state to current clinical, prevention and reporting pathways.
Permissible next actions depend on diagnostic uncertainty, pregnancy context, exposure route and jurisdiction.
Clinical action selection
Identify the guidance and unresolved conditions governing care decisions.
Management and review gates
Record which current management pathway applies and which unresolved diagnostic or complication questions affect proposed actions.
- Which current clinical guidance supports the proposed management for this presentation? provenance
- How do unresolved dengue, pregnancy status or suspected complications change the next action? action
Transmission prevention
Select prevention advice using route-specific evidence and current guidance.
Dated prevention advice
Treat precaution durations and triggers as versioned guidance requirements rather than timeless properties of Zika fever.
- Which mosquito-exposure, sexual-transmission or pregnancy-planning precautions apply to this situation? action
- Which authority and revision define each precaution's duration and starting event? provenance
Surveillance interpretation
Keep reporting classifications and population estimates tied to their ascertainment methods.
Reportable case and denominator
Separate clinical disease episodes, reported cases, detected infections and seroprevalence when interpreting occurrence.
- Does this episode meet the jurisdiction's reporting definition, and which revision applies? action
- What population, year, geography, numerator and denominator support an occurrence estimate? measurement
- Does ascertainment measure symptomatic disease, detected infection or prior exposure, and what limitations are documented? boundary
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- This is recall-based information; no sources were consulted.
- The listed kinds are clinical distinctions, not a formal exhaustive subtype classification; fever is not present in every symptomatic case.
- Verify current case definitions, testing algorithms and coding revisions; prevalence requires a specified population, location, year and ascertainment method.
- Which of these check these first hold for the sense of Zika fever this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Uncomplicated symptomatic Zika virus disease
- Zika virus disease with neurological complications
- Which of these kinds and varieties hold for the sense of Zika fever this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- ICD-10 - A92.5 - Zika virus disease; confirm the applicable WHO edition or national modification before coding.
- Which of these identifiers and schemes hold for the sense of Zika fever this model covers, and on what evidence? provenance
Standards and regulation
Recalled without web access and unsourced; every item is a lead to verify.
- World Health Organization surveillance case definitions distinguish suspected, probable and confirmed Zika virus disease.
- World Health Organization laboratory guidance addresses testing for Zika virus infection.
- Which of these standards and regulation hold for the sense of Zika fever this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Clinical assessment of compatible rash, fever, conjunctivitis and joint pain in an epidemiologically relevant setting.
- Laboratory-supported differentiation from dengue and chikungunya.
- Public-health surveillance and outbreak investigation.
- Assessment and follow-up of pregnancies with possible maternal Zika virus infection.
- Which of these real-world use hold for the sense of Zika fever this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Incubation period in symptomatic infection - 3-14 - days
- Usual duration of acute symptoms - 2-7 - days
- Which of these typical measurements hold for the sense of Zika fever this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Infection during pregnancy can cause congenital Zika syndrome, including microcephaly and other brain and eye abnormalities.
- Guillain-Barré syndrome can occur in association with infection.
- Many infections are asymptomatic, limiting detection through symptom-based surveillance.
- Serological cross-reactivity with other flaviviruses can complicate interpretation of antibody tests.
- Sexual and maternal-fetal transmission mean mosquito exposure alone does not define transmission risk.
- Which of these failure modes and hazards hold for the sense of Zika fever this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Transmission risk varies with competent mosquito populations, climate, population immunity and outbreak history.
- Prior dengue infection or other flavivirus exposures can affect serological interpretation.
- Reporting obligations and diagnostic testing pathways vary by jurisdiction.
- Which of these regional variation hold for the sense of Zika fever this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Zika virus infection - Infection includes asymptomatic cases; Zika fever denotes clinical illness, although terminology sometimes overlaps.
- Dengue - Caused by dengue viruses rather than Zika virus; overlapping symptoms require epidemiological and laboratory differentiation.
- Chikungunya - Caused by chikungunya virus; prominent or persistent joint pain is suggestive, but laboratory testing distinguishes the infections.
- Congenital Zika syndrome - A constellation of fetal or infant abnormalities resulting from infection in utero, rather than the acute febrile illness.
- Zika virus - The infectious agent, rather than the disease it causes.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of Zika fever this model covers, and on what evidence? provenance
What the second pass must settle
- Does the authoritative registry source intend 'Zika fever' to include asymptomatic Zika virus infection, and does an existing Vercy world model already own that concept?
- Which exact ICD-10, ICD-11 and SNOMED CT codes and editions preserve the intended boundary between acquired disease, infection and congenital disease?
- Which issuing body's clinical and surveillance definitions should govern the intended deployment, and how should disagreements between them be represented?
- Which current jurisdiction-specific testing, pregnancy follow-up and transmission-prevention guidance should be operationalised, including local assay availability?
- Which population- and year-specific occurrence estimates distinguish symptomatic Zika disease from infection and quantify ascertainment uncertainty?