hand, foot and mouth disease
Enable an agent to recognise hand, foot and mouth disease, assess an attributed illness episode, and identify appropriate assessment, care and transmission-control actions from documented evidence.
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 hand, foot and mouth disease, assess an attributed illness episode, and identify appropriate assessment, care and transmission-control actions from documented evidence.
Hand, foot and mouth disease is an acute contagious illness caused by several enteroviruses, typically producing fever, oral vesicles or ulcers, and a rash on the hands and feet, predominantly in young children.
It can be Compare a documented oral and skin presentation with a sourced HFMD case definition and flag missing observations.; Track an episode's symptom course and hydration evidence to identify reassessment needs.; Associate laboratory evidence with an episode while preserving uncertainty about causal attribution.; Retrieve applicable clinical guidance when severity or complications require assessment.; Determine which local attendance, hygiene and reporting guidance applies to the affected setting.; Compare population estimates only after aligning case definitions, denominators, locations and periods..
Distinguishing features
Check that the concept concerns human HFMD rather than animal foot-and-mouth disease, which is unrelated. [CDC causes](https://www.cdc.gov/hand-foot-mouth/causes/index.html)
Assess the combination of mouth sores and hand or foot rash, with fever recorded separately; do not infer the diagnosis from the disease name alone. [CDC symptoms](https://www.cdc.gov/hand-foot-mouth/signs-symptoms/index.html)
Require lesion distribution and oral examination evidence when comparing HFMD with an oral-only syndrome or another vesicular rash.
Distinguish clinical HFMD from an enterovirus-positive result: record the clinical syndrome and pathogen evidence as separate assertions.
Treat age as contextual evidence rather than an exclusion rule: HFMD is common below age five but can affect other ages. [CDC overview](https://www.cdc.gov/hand-foot-mouth/index.html)
Scope
+ Clinical recognition of typical, incomplete and atypical presentations
+ Enterovirus attribution and interpretation of supporting laboratory evidence
+ Episode timing, hydration, severity, complications and recovery
+ Exposure, transmission and setting-specific prevention decisions
+ Versioned diagnostic definitions, terminology mappings and population evidence
- The patient's complete health record and unrelated conditions
- Care encounters, staffing, billing and treatment administration records
- General enterovirus taxonomy and laboratory assay specifications
- Animal foot-and-mouth disease
- Independent models of alternative rash illnesses
- Institution-wide outbreak management beyond HFMD-specific requirements
Characteristics
- Diagnostic assertion
- Suspected, clinically diagnosed, laboratory-supported, rejected or unresolved; retain the issuing definition Prevents a provisional label or positive assay from silently becoming a confirmed disease episode.
- Lesion phenotype
- Oral and skin sites, morphology, pain, extent; absent, present or unexamined at each site Supports recognition and comparison with competing explanations.
- Episode timing
- Dates and elapsed days for fever, oral lesions, skin lesions and recovery; uncertainty recorded Makes progression and persistent symptoms interpretable.
- Hydration evidence
- Fluid intake in mL over a stated interval when available, urine frequency and clinician-assessed hydration Connects painful oral symptoms to a concrete assessment need.
- Severity and complication assessment
- Assessment pending, uncomplicated, complication suspected or complication documented; criteria and timestamp required Supports escalation without assuming that every episode follows the usual course.
- Causal attribution
- Episode linked to an identified or suspected enterovirus, supporting specimen and assay, or unknown agent HFMD has multiple viral causes; the syndrome does not establish a particular virus. [CDC causes](https://www.cdc.gov/hand-foot-mouth/causes/index.html)
- Exposure setting
- Household, childcare, school or other contact setting, with exposure dates and confidence Supports plausible exposure assessment and targeted prevention.
- Terminology mapping
- Coding system, jurisdiction, release, code, preferred term and mapping fidelity Keeps administrative classification distinct from clinical diagnostic evidence.
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 · 19 findings · 29 questions.
Syndrome recognition Evidence needed to recognise HFMD and keep its diagnostic boundaries explicit.
The characteristic name can encourage diagnosis from an incomplete symptom checklist.
Oral and cutaneous pattern
Observed lesion sites, morphology and accompanying symptoms.
Documented presentation
Record oral lesions, hand and foot involvement, other affected sites and fever independently, including unexamined sites.
- Which oral and skin sites were examined, and what lesion morphology, pain and distribution were documented? measurement
- Which sourced definition supports recognising this presentation as typical, incomplete or atypical HFMD? definition
Diagnostic boundaries
Competing explanations and the status of the diagnostic assertion.
Differential and confidence
Keep competing diagnoses and unresolved evidence visible rather than treating all oral ulcers or acral rashes as HFMD.
- What observations support HFMD over herpangina, gingivostomatitis, varicella or another explanation for this presentation? boundary
- Who assigned the diagnostic status, on what date, and using which clinical or surveillance definition? provenance
Viral attribution Causal evidence and its limits for the HFMD syndrome.
An agent must distinguish a clinical syndrome, a detected virus and a supported causal claim.
Etiologic identity
Attribution to a specific enterovirus where evidence permits.
Attributed enterovirus
Allow unknown attribution and distinguish suspected from identified agents, including coxsackievirus A16, coxsackievirus A6 and EV-A71. [CDC causes](https://www.cdc.gov/hand-foot-mouth/causes/index.html)
- Is the attributed virus supported by testing of this episode, inferred from an outbreak, or unknown? provenance
- Does the evidence identify a particular viral type or only a broader enterovirus group? boundary
Laboratory interpretation
Specimen, timing and assay context needed to interpret a result.
Episode-linked test evidence
Represent laboratory results with their collection context and interpretive limits; do not make testing a universal prerequisite without a cited definition.
- Which specimen and assay produced the result, and when was collection relative to symptom onset? measurement
- What does the applicable guidance allow this result to establish about the current HFMD episode? boundary
Course and care decisions Episode progression and evidence that changes assessment or care needs.
Oral pain, hydration and uncommon complications matter more to action than the disease label alone.
Symptoms and hydration
Symptom trajectory and ability to maintain intake.
Oral pain and fluid balance
Record drinking difficulty alongside intake and hydration observations. Painful mouth sores can interfere with swallowing. [CDC symptoms](https://www.cdc.gov/hand-foot-mouth/signs-symptoms/index.html)
- How have mouth pain, drinking, urine output and fever changed since onset? measurement
- Which age-appropriate, sourced criteria indicate that hydration or symptom control needs clinical reassessment? action
Complications and resolution
Evidence for escalation, recovery or reconsideration of the diagnosis.
Departure from expected course
Separate recovery assessment from suspected complications and record the criteria behind escalation; most children have mild symptoms lasting 7 to 10 days. [CDC symptoms](https://www.cdc.gov/hand-foot-mouth/signs-symptoms/index.html)
- Are symptoms improving, persisting or worsening, and are there documented neurologic or other complication concerns? measurement
- Which current guideline determines the urgency of assessment and the evidence required to mark this episode resolved? action
Transmission and setting Exposure evidence and context-specific prevention requirements.
An individual HFMD episode can require actions involving household or group settings.
Exposure and clustering
Contact history and links to other episodes.
Plausible exposure links
Record temporally plausible contacts and cluster membership without asserting a proven transmission chain.
- Which household, childcare, school or other contacts occurred before onset, and on what dates? measurement
- What evidence supports linking this episode to a cluster rather than merely sharing a setting? provenance
Prevention and participation
Applicable guidance for hygiene, attendance and notification.
Setting-specific actions
Attach prevention and participation decisions to a named authority, jurisdiction and effective date; keep clinical recovery distinct from permission to return.
- Which local HFMD guidance governs hygiene, childcare or school attendance, and outbreak notification? provenance
- Given the recorded symptoms and setting, what actions does that guidance require and when must they be reviewed? action
Classification and population evidence Versioned concept mappings and interpretable measures of disease occurrence.
Codes and case counts can describe different boundaries unless their definitions travel with them.
Versioned concept mapping
Relationship between the registry concept and clinical terminologies.
Verified disease mappings
Require verification of ICD-10, ICD-11 and SNOMED CT mappings in the applicable releases, including whether each mapping is exact or broader.
- Which verified codes and preferred terms map to HFMD in the relevant ICD and SNOMED CT releases? provenance
- Does each mapping denote the disease itself, a broader enteroviral syndrome, or a different recordable concept? boundary
Population and surveillance
Population context for reported HFMD occurrence and severity.
Denominated frequency
Distinguish incidence, prevalence, notified cases and hospital series; retain age range, location, period, denominator and ascertainment method.
- What population, year, denominator and case definition support the reported HFMD frequency? measurement
- How do reporting coverage, testing selection and recruitment setting limit comparison with other estimates? 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 recalled knowledge, not source-verified research; no sources were consulted.
- Verify coding revisions, national reporting requirements, and any formal surveillance case definition before operational use.
- Timing ranges are approximate; prevalence, pathogen distribution, and complication rates require a specified population, period, and source.
- Which of these check these first hold for the sense of hand, foot and mouth disease this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Typical hand, foot and mouth disease
- Atypical hand, foot and mouth disease, often associated with coxsackievirus A6
- Which of these kinds and varieties hold for the sense of hand, foot and mouth disease this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- WHO ICD-10 - B08.4 - Enteroviral vesicular stomatitis with exanthem; confirm the applicable national modification and revision when coding.
- Which of these identifiers and schemes hold for the sense of hand, foot and mouth disease 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 ICD-10 classifies the disease under B08.4; this classification is not a diagnostic criterion set.
- Which of these standards and regulation hold for the sense of hand, foot and mouth disease 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 recognition of a usually self-limited childhood infectious illness
- Surveillance and investigation of outbreaks in childcare settings and schools
- Enterovirus testing and typing in selected severe, atypical, or outbreak-associated cases
- Distinguishing the disease from an individual infection episode, the recorded diagnosis, and the encounter providing care
- Which of these real-world use hold for the sense of hand, foot and mouth disease 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 - Approximately 3-6 - days
- Usual duration of uncomplicated illness - Approximately 7-10 - days
- Which of these typical measurements hold for the sense of hand, foot and mouth disease 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.
- Painful mouth lesions can reduce fluid intake and cause dehydration.
- Transmission can occur through fecal contamination, respiratory and oral secretions, blister fluid, and contaminated objects.
- Rare neurological complications include meningitis, encephalitis, and acute flaccid paralysis, particularly with enterovirus A71.
- Severe enterovirus A71-associated disease can involve cardiopulmonary deterioration.
- Atypical widespread lesions can be mistaken for other vesicular skin diseases; temporary nail shedding can follow recovery.
- Which of these failure modes and hazards hold for the sense of hand, foot and mouth disease this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Circulating enterovirus types and the proportion of severe cases vary by place and outbreak.
- Large outbreaks associated with enterovirus A71 have been especially prominent in parts of East and Southeast Asia.
- Seasonality varies with climate, with summer and autumn peaks common in temperate regions.
- Which of these regional variation hold for the sense of hand, foot and mouth disease 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.
- Foot-and-mouth disease - A distinct aphthovirus infection principally affecting cloven-hoofed animals; it is not the human enteroviral illness.
- Herpangina - An enteroviral syndrome with lesions predominantly in the posterior mouth and throat, usually without the characteristic hand and foot rash.
- Varicella - Caused by varicella-zoster virus and typically produces a generalized itchy eruption with lesions in successive stages.
- Primary herpetic gingivostomatitis - Usually caused by herpes simplex virus, with prominent gingival inflammation and painful oral lesions rather than the characteristic acral eruption.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of hand, foot and mouth disease this model covers, and on what evidence? provenance
What the second pass must settle
- Which issuing bodies and current revisions provide the clinical and surveillance definitions needed for the intended jurisdictions, including atypical presentations?
- What are the verified ICD-10, ICD-11 and SNOMED CT mappings, release identifiers and mapping limitations for this registry concept?
- Which age-specific escalation and recovery criteria should govern hydration concerns, persistent symptoms and suspected complications?
- Which current local policies govern attendance, reporting and prevention, including any locally available vaccination programme and its viral coverage?
- Which population-based studies provide comparable HFMD incidence or prevalence estimates with explicit age groups, locations, years and ascertainment methods?