chikungunya
Enable an agent to recognise a possible chikungunya episode, assess diagnostic certainty and functional burden, and identify appropriate clinical 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 a possible chikungunya episode, assess diagnostic certainty and functional burden, and identify appropriate clinical and transmission-prevention actions.
Chikungunya is a mosquito-borne infectious disease caused by chikungunya virus, typically producing acute fever and marked joint pain that can persist or recur after the acute illness.
It can be Assemble an episode timeline linking exposure, symptom onset, specimen collection, and recovery.; Identify missing diagnostic evidence and suggest clinician review of whether additional testing is appropriate.; Flag unresolved dengue assessment before an agent proposes pain-management options.; Track joint symptoms and everyday function to support follow-up or specialist referral.; Identify time-sensitive mosquito-bite prevention and jurisdiction-specific reporting handoffs.; Retrieve current, jurisdiction-specific vaccine guidance for an exposed or travelling person without assuming universal eligibility..
Distinguishing features
Require a relationship to chikungunya virus infection: fever and joint pain alone do not identify the disease, and the disease episode is distinct from the virus entity.
Record abrupt fever with prominent, often bilateral joint pain as a recognition pattern, while retaining dengue and Zika as competing explanations; symptoms alone cannot reliably establish the diagnosis. See [WHO chikungunya fact sheet](https://www.who.int/en/news-room/fact-sheets/detail/chikungunya).
Distinguish appropriately timed viral RNA detection from antibody evidence: an isolated antibody result must not automatically identify when infection occurred. See [CDC diagnostic guidance](https://www.cdc.gov/chikungunya/hcp/diagnosis-testing/index.html).
Treat persistent or relapsing joint symptoms after the acute illness as a possible chikungunya-related course, while separately evaluating other rheumatologic explanations. See [CDC clinical guidance](https://www.cdc.gov/chikungunya/hcp/clinical-signs/index.html).
Scope
+ Recognition and evidence-based classification of a suspected or confirmed chikungunya episode
+ Exposure history and plausible acquisition context
+ Interpretation of diagnostic evidence relative to symptom onset
+ Acute illness, complications, persistent joint symptoms, and functional recovery
+ Disease-specific care constraints, prevention opportunities, and public-health handoffs
- Chikungunya virus taxonomy, genome structure, and laboratory propagation
- Aedes mosquito biology and comprehensive vector-control programme design
- Full models of dengue, Zika, malaria, and inflammatory arthritis
- Vaccine manufacturing, product specifications, and regulatory dossiers
- Population-level outbreak simulation and general healthcare service management
Characteristics
- Episode classification
- Suspected, probable, confirmed, excluded, or unresolved, using a named case definition and version Separates a recognition hypothesis from a classification supported by specified evidence.
- Time since symptom onset
- Days, with onset date and uncertainty interval Anchors diagnostic interpretation, disease course, and transmission-prevention timing.
- Acquisition context
- Links to residence, travel, exposure dates, local transmission evidence, and possible transmission route Supports exposure plausibility without treating geography as diagnostic proof.
- Diagnostic evidence
- Links to specimens, collection dates, assay types, results, laboratories, and confirmatory tests Makes classification traceable and allows reassessment when additional results arrive.
- Joint symptom distribution
- Named joints, laterality, pain, swelling, stiffness, and clinician-observed inflammation Distinguishes reported arthralgia from documented arthritis and supports longitudinal comparison.
- Pain and functional limitation
- Named pain scale and score; walking, self-care, sleep, and work limitations with observation dates Captures disability that fever resolution alone would miss.
- Disease course
- Acute illness, persistent symptoms, relapsing symptoms, recovered, or uncertain; phase thresholds explicitly sourced Prevents inconsistent duration labels from obscuring progression.
- Severe disease vulnerability
- Age, relevant comorbidities, pregnancy timing, and neonatal exposure context Provides context for clinician assessment and follow-up priority.
- Dengue assessment
- Not assessed, under investigation, supported, or excluded under a documented clinical assessment Preserves a competing diagnosis that can change medication safety decisions.
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 · 11 layers · 18 findings · 28 questions.
Disease identity and boundaries Establish what qualifies as a chikungunya disease episode and preserve competing explanations.
The registry lacks a definition, and the disease must not be conflated with its pathogen, an exposure, or an undifferentiated febrile illness.
Episode definition
Represent disease identity and case classification explicitly.
Case definition and certainty
Record the authority and version of the case definition, the evidence satisfying its criteria, and whether the label serves clinical care or surveillance.
- Which clinical or surveillance definition governs this episode's suspected, probable, or confirmed classification? definition
- Does the record describe symptomatic disease, asymptomatic infection, past infection, or exposure without evidence of infection? boundary
Competing and coexisting diagnoses
Separate chikungunya from illnesses with overlapping presentations without assuming mutual exclusion.
Differential evidence
Retain evidence for dengue, Zika, other exposure-relevant febrile illnesses, and alternative causes of joint symptoms.
- Which findings and tests support chikungunya over dengue, Zika, or other locally relevant diagnoses? boundary
- What evidence supports a concurrent infection or an independent joint disorder rather than a single explanation? provenance
Exposure and transmission Connect the episode to plausible acquisition and opportunities to prevent onward transmission.
Chikungunya interpretation depends on where and when exposure occurred and on the relationship between an infected person and mosquito vectors.
Acquisition history
Reconstruct location and exposure timing without inferring infection solely from travel.
Plausible exposure window
Link residence, travel, mosquito exposure, and dated local transmission reports to symptom onset; preserve uncertainty about acquisition location.
- Which locations and exposure dates plausibly precede onset under the incubation range used by the selected reference? measurement
- Which dated source establishes chikungunya transmission at each proposed acquisition location? provenance
Onward transmission context
Identify mosquito-mediated prevention needs and special exposure pathways.
Transmission-prevention window
Record bite-prevention needs during early illness and any maternal illness near delivery or blood-exposure context requiring specific assessment. CDC advises preventing mosquito exposure during the first week of illness. See [CDC treatment and prevention guidance](https://www.cdc.gov/chikungunya/hcp/treatment-prevention/).
- Where is the person relative to symptom onset, and what mosquito-bite prevention measures are feasible now? action
- Is there a perinatal or blood-exposure circumstance requiring a separate clinical or public-health handoff? boundary
Diagnostic evidence and timing Interpret laboratory evidence in its temporal and methodological context.
A result's meaning changes with collection timing and assay type; an unqualified positive or negative label loses essential information.
Specimen and assay timeline
Relate each result to symptom onset and the test's intended detection window.
Time-qualified test result
Capture specimen type, collection date, assay, result, and laboratory interpretation. RNA testing is used during acute infection, while serology becomes useful after the first week. See [CDC diagnostic guidance](https://www.cdc.gov/chikungunya/hcp/diagnosis-testing/index.html).
- How many days after onset was each specimen collected, and was the assay appropriate for that interval? measurement
- Does a negative result justify exclusion, or does its timing warrant clinician-directed follow-up testing? action
Confirmation and discordance
Resolve provisional or conflicting evidence without overstating certainty.
Antibody confirmation and attribution
Record whether a positive IgM result received confirmatory neutralizing-antibody testing and distinguish evidence of infection from attribution of the current symptoms. See [CDC diagnostic guidance](https://www.cdc.gov/chikungunya/hcp/diagnosis-testing/index.html).
- What confirmation supports the antibody result, and what limitations did the laboratory report? provenance
- How do prior illness, vaccination history, and conflicting results affect attribution to the current episode? boundary
Clinical course and joint burden Track acute severity and the prolonged musculoskeletal consequences that can dominate recovery.
Chikungunya can remain disabling after the initial fever has resolved, so episode state cannot be represented by infection confirmation alone.
Acute manifestations and severity
Record the presenting syndrome, clinical deterioration, and vulnerability context.
Acute burden and escalation
Track fever, joint pain, hydration, functional ability, and suspected organ involvement alongside age and comorbidities; distinguish risk factors from observed complications.
- What are the current measured symptoms, functional limitations, and clinician-observed signs of complications? measurement
- Which current findings meet the applicable clinical pathway's criteria for urgent assessment or hospital care? action
Persistent musculoskeletal course
Follow continuing or relapsing joint symptoms and recovery of everyday function.
Joint symptom trajectory
Distinguish pain, inflammatory joint findings, and disability over time, preserving the evidence for attributing them to chikungunya.
- Which joints and daily activities remain affected, for how long, and with what change on repeated assessments? measurement
- What supports post-chikungunya attribution, and what findings require investigation for another rheumatologic condition? boundary
Care, prevention, and handoffs Connect disease evidence to clinician-led care and current prevention or reporting requirements.
Safe actions depend on unresolved differential diagnoses, the patient's course, and changing local guidance.
Symptom care and follow-up
Make treatment prerequisites and reassessment needs explicit.
Care decision constraints
Record the clinician's supportive-care plan and medication constraints. CDC advises managing suspected chikungunya as dengue until dengue is ruled out, with acetaminophen preferred initially for fever and pain. See [CDC treatment guidance](https://www.cdc.gov/chikungunya/hcp/treatment-prevention/).
- Has dengue been sufficiently assessed before aspirin or an NSAID is considered, and what patient-specific contraindications apply? action
- What persistent pain, inflammation, or functional limitation warrants reassessment, rehabilitation, or specialist review? action
Prevention and public-health interface
Identify current vaccine guidance and reporting duties without embedding universal product or jurisdiction assumptions.
Dated prevention and reporting rules
Link vaccination assessment and suspected or confirmed case reporting to the relevant authority, jurisdiction, effective date, and individual circumstances.
- Which current local vaccine recommendations apply to this person's age, health status, travel, and exposure context? action
- Which authority requires notification of this episode, using what case category and deadline? provenance
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 describes the human infectious disease, rather than the virus or an abstract state implied by the supplied domain code.
- Time boundaries separating acute, post-acute and chronic disease vary between clinical frameworks.
- This is a recall-based account; current geographic distribution, vaccine recommendations and national reporting requirements require verification.
- Which of these check these first hold for the sense of chikungunya this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Acute chikungunya
- Post-acute chikungunya
- Chronic chikungunya-associated joint disease
- Which of these kinds and varieties hold for the sense of chikungunya 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 - A92.0 - WHO classification code for chikungunya virus disease.
- Which of these identifiers and schemes hold for the sense of chikungunya 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 diagnosis and differential diagnosis of fever with prominent joint pain.
- Public-health surveillance of mosquito-borne disease and outbreaks.
- Laboratory confirmation using viral RNA detection or antibody testing, depending on time since symptom onset.
- Planning mosquito control and prevention of mosquito bites.
- Assessment and follow-up of persistent joint pain and functional impairment.
- Which of these real-world use hold for the sense of chikungunya 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 after an infective mosquito bite - Usually 4-8; reported range approximately 2-12 - days
- Duration of persistent joint symptoms - Months to years in some affected people - time
- Which of these typical measurements hold for the sense of chikungunya 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.
- Persistent or recurrent joint pain can cause substantial disability.
- Clinical overlap with dengue and Zika can lead to misclassification.
- Rare severe manifestations include neurological, cardiac and ocular complications.
- Newborns exposed around delivery, older adults and people with underlying conditions have increased risk of severe disease.
- Aedes mosquitoes can sustain outbreaks where vector populations and environmental conditions permit transmission.
- Which of these failure modes and hazards hold for the sense of chikungunya this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Transmission has occurred across Africa, Asia, the Americas and islands of the Indian and Pacific oceans.
- Aedes aegypti and Aedes albopictus differ in local abundance and importance as vectors.
- Temperate regions can experience seasonal local transmission when competent mosquitoes are present and the virus is introduced.
- Which of these regional variation hold for the sense of chikungunya 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.
- Chikungunya virus - The virus is the infectious agent; chikungunya is the disease it causes.
- Dengue - Dengue is caused by dengue viruses; symptoms and mosquito vectors overlap, so laboratory testing may be needed to distinguish infections.
- Zika virus disease - Zika is caused by Zika virus and has a different complication profile; overlapping symptoms can require laboratory differentiation.
- Rheumatoid arthritis - Rheumatoid arthritis is an autoimmune inflammatory disease; chronic chikungunya-associated arthritis follows chikungunya infection and can resemble it clinically.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of chikungunya this model covers, and on what evidence? provenance
What the second pass must settle
- Which authoritative case definitions and duration thresholds should govern acute, post-acute, and chronic states across the jurisdictions this model must serve?
- Which validated measures best capture chikungunya-related joint disability across ages, languages, and care settings?
- What evidence is sufficient to attribute persistent inflammatory joint disease to chikungunya rather than a coincident or newly apparent rheumatologic disorder?
- How should prior vaccination and assay-specific limitations alter interpretation of antibody evidence for a new suspected episode?
- Which current clinical pathways should supply escalation criteria and persistent-joint-symptom management rules, and how will their updates be incorporated?