Hand, Foot and Mouth Disease (HFMD)
Summary
Hand, Foot and Mouth Disease (HFMD) is a common, highly contagious viral illness primarily affecting children under 5 years of age. It is caused by Enteroviruses, most commonly Coxsackievirus A16 (classic mild form) and Enterovirus 71 (EV71) (associated with severe neurological complications). The disease is characterised by a triad of features: Oral Ulcers (painful), Vesicular Rash on Hands and Feet, and Low-Grade Fever. The rash may also affect the buttocks. HFMD is self-limiting in most cases, resolving within 7-10 days. Management is entirely supportive (analgesia, hydration). Key concerns include dehydration (due to painful oral ulcers preventing drinking) and rarely, severe neurological and cardiopulmonary complications (particularly with EV71 outbreaks in Asia). There is no vaccine or specific antiviral treatment available in the UK. [1,2]
Clinical Pearls
"Hand, Foot, Mouth, Bum": The rash classically affects hands, feet, mouth, and BUTTOCKS. Don't forget the bottom!
NOT Herpangina: Herpangina is posterior pharynx/soft palate ulcers ONLY (no limb rash). HFMD includes limb rash.
EV71 is Dangerous: Most HFMD is mild (Coxsackie A16). But EV71 outbreaks (Asia) cause encephalitis, pulmonary oedema, and death.
Nail Changes (Onychomadesis): Nails may shed 1-2 months post-infection. Transient. Grows back normally.
Demographics
| Factor | Notes |
|---|---|
| Age | Peak: less than 5 years (Especially less than 2 years). Can affect older children and adults. |
| Season | Summer and Autumn (UK). Year-round in tropical regions. |
| Setting | Outbreaks in nurseries, childcare centres, schools. |
Causative Organisms
| Virus | Notes |
|---|---|
| Coxsackievirus A16 | Most common cause. Usually mild self-limiting illness. |
| Coxsackievirus A6 | Associated with more extensive rash, can affect adults, atypical presentations. |
| Enterovirus 71 (EV71) | Associated with severe neurological complications (Encephalitis, Acute Flaccid Paralysis, Death). Major concern in Asia-Pacific outbreaks. |
| Other Enteroviruses | Coxsackievirus A10, Echoviruses, etc. |
Transmission
- Faecal-Oral Route: Main route (Contaminated hands, surfaces, objects).
- Respiratory Droplets: Vesicle fluid, oral secretions.
- Incubation: 3-7 days.
- Infectious Period: Most infectious in first week. Virus shed in stool for weeks.
Mechanism
- Entry: Virus enters via oral/pharyngeal mucosa or GI tract.
- Local Replication: In pharyngeal lymphoid tissue and Peyer's patches.
- Primary Viraemia: Spreads to reticuloendothelial system (Liver, Spleen, Lymph nodes).
- Secondary Viraemia: Spreads to target tissues (Skin of hands/feet, Oral mucosa, CNS in severe cases).
- Immune Response: Vesicle formation represents inflammatory response. Self-limiting as immunity develops.
Severe Disease (EV71)
- EV71 has neurotropism → Brainstem encephalitis.
- Autonomic dysregulation → Pulmonary oedema, Cardiovascular collapse.
| Condition | Key Features |
|---|---|
| Hand, Foot and Mouth Disease | Oral ulcers + Papulovesicular rash on hands, feet, buttocks. |
| Herpangina | Posterior pharynx/soft palate ulcers ONLY. No limb rash. Also Coxsackie. |
| Chickenpox (Varicella) | Generalised vesicular rash ("dew drops on rose petal"), Centripetal distribution, All stages present. |
| Primary Herpes Gingivostomatitis | Painful oral ulcers + Gum involvement. High fever. Usually HSV-1. |
| Impetigo | Honey-crusted lesions. Bacterial (Staph/Strep). |
| Scabies | Itchy papules, Burrows in web spaces, Family clustering. |
| Erythema Multiforme | Target lesions. Drug or infection trigger. |
| Stevens-Johnson Syndrome | Mucosal erosions, Skin blistering, Systemically unwell. |
Typical Progression (Days)
| Day | Features |
|---|---|
| Day 1-2 | Prodrome: Low-grade fever (38-39°C), Malaise, Sore throat, Reduced appetite. |
| Day 2-3 | Oral Ulcers: Painful vesicles → Ulcers on tongue, buccal mucosa, hard palate. |
| Day 3-4 | Skin Rash: Papules → Vesicles on hands (palms), feet (soles), and buttocks. |
| Day 7-10 | Resolution: Fever settles, ulcers heal, rash crusts and fades. |
Rash Characteristics
| Feature | Notes |
|---|---|
| Morphology | Papules → Vesicles (Oval, Grey centre, Red halo). May become pustular. |
| Distribution | Palms, Soles (Unusual – most rashes spare these areas). Dorsum of hands/feet. Buttocks. |
| Non-Blanching? | Can be non-blanching in early maculopapular phase (Concern re: meningococcal – Check for other features). |
Oral Lesions
Late Complication: Nail Shedding (Onychomadesis)
Diagnosis
- Clinical Diagnosis: Based on classic triad (Oral ulcers, Hand/Foot rash, +/- Buttock involvement).
- No routine investigation required for uncomplicated cases.
When to Investigate
| Indication | Investigation |
|---|---|
| Severe/Atypical Case | Throat/Stool Swab for Enterovirus PCR. |
| Neurological Signs | Lumbar Puncture (CSF PCR), MRI Brain. |
| Suspected Outbreak | Public Health notification. Typing for EV71. |
Management Algorithm
HAND, FOOT AND MOUTH DISEASE
(Oral ulcers + Hand/Foot rash)
↓
CLINICAL ASSESSMENT
- Is child drinking? (Hydration status)
- Any neurological signs? (Lethargy, Weakness, Tremor)
- Any respiratory distress?
↓
UNCOMPLICATED (Most Cases)
┌──────────────────────────────────────────────────────────┐
│ SUPPORTIVE MANAGEMENT (No Specific Treatment) │
│ │
│ ANALGESIA: │
│ - Paracetamol / Ibuprofen (Oral pain relief) │
│ - Topical Anaesthetics: │
│ • Benzydamine spray/mouthwash (Difflam) │
│ • Lidocaine gel (Apply before feeds) │
│ │
│ HYDRATION: │
│ - Encourage small frequent sips of cool fluids │
│ - Avoid acidic drinks (Orange juice stings ulcers) │
│ - Ice lollies/Cold soft foods are soothing │
│ │
│ SKIN CARE: │
│ - No specific treatment needed for rash │
│ - Keep lesions clean and dry │
│ - Calamine lotion for itch if needed │
│ │
│ DURATION: │
│ - Self-limiting. Resolves in 7-10 days. │
└──────────────────────────────────────────────────────────┘
↓
RED FLAGS → HOSPITAL REFERRAL
┌──────────────────────────────────────────────────────────┐
│ ADMIT IF: │
│ - Severe dehydration (Unable to drink, Reduced urine) │
│ - Neurological signs (Lethargy, Tremor, Limb weakness, │
│ Seizures, Ataxia) │
│ - Respiratory distress │
│ - Prolonged high fever (>72 hours) │
│ - Immunocompromised patient │
└──────────────────────────────────────────────────────────┘
Infection Control
| Measure | Details |
|---|---|
| Exclusion from Nursery/School | Until clinically well (No fever). Some policies exclude until vesicles crusted. |
| Hand Hygiene | Frequent handwashing (Especially after nappy changes). |
| Surface Cleaning | Disinfect toys, surfaces (Virus survives on fomites). |
| Avoid Sharing | Utensils, Towels, Cups. |
| Complication | Notes |
|---|---|
| Dehydration | Most common. Due to painful oral ulcers. May need IV fluids. |
| Secondary Bacterial Infection | Rare. Cellulitis if lesions become infected. |
| Onychomadesis (Nail Shedding) | Benign, temporary. 4-8 weeks post-illness. |
| Neurological (EV71) | Aseptic Meningitis, Brainstem Encephalitis, Acute Flaccid Paralysis. |
| Cardiopulmonary (EV71) | Pulmonary Oedema, Myocarditis, Cardiovascular Collapse (Fatal). |
- Excellent prognosis for typical HFMD (Coxsackie A16).
- Self-limiting: Fever 2-3 days. Ulcers heal 5-7 days. Rash fades 7-10 days.
- Full Recovery: No long-term sequelae.
- EV71: Carries significant mortality risk in severe cases (1-2% in outbreaks with neurological involvement).
Key Guidelines
| Guideline | Organisation | Key Recommendations |
|---|---|---|
| HFMD Management | PHE | Supportive care. Exclusion guidance. |
| EV71 Surveillance | WHO | Outbreak reporting and surveillance in Asia-Pacific. |
Prevention
- Vaccine: EV71 vaccines developed and used in China/Taiwan. Not yet available in UK/Europe.
- Hygiene: Most important preventive measure.
What is Hand, Foot and Mouth Disease?
It is a very common viral infection in young children. It causes mouth ulcers (which are painful) and a spotty rash on the hands and feet. Sometimes the bottom is affected too.
Is it the same as Foot and Mouth Disease in animals?
No, completely different. Foot and Mouth in cattle is caused by a different virus that does not affect humans.
Is it serious?
In the UK, it is usually a mild illness that gets better on its own in about a week. Very rarely, a specific virus type (EV71) can cause more serious complications, but this is mainly seen in Asia.
How do I help my child?
- Pain relief: Paracetamol or Ibuprofen.
- Fluids: Encourage small sips of cool water or milk. Avoid acidic drinks (Orange juice stings!). Ice lollies are soothing.
- Mouth spray: Benzydamine (Difflam) spray can numb the mouth ulcers.
- Keep them comfortable: Usually fever settles in 2-3 days.
Can they go to nursery?
They should stay home until the fever has gone and they feel well. Some nurseries ask that the blisters have crusted over. Check with your setting.
Primary Sources
- Ooi MH, et al. Clinical features, diagnosis, and management of enterovirus 71. Lancet Neurol. 2010;9(11):1097-1105. PMID: 20965438.
- Public Health England. Guidance on infection control in schools and other childcare settings. 2017. Gov.uk
Common Exam Questions
- Classic Triad: "What are the features of HFMD?"
- Answer: Oral Ulcers, Hand Rash, Foot Rash (+/- Buttock).
- Causative Organism: "Which virus causes most UK cases?"
- Answer: Coxsackievirus A16.
- Dangerous Variant: "Which enterovirus causes neurological complications?"
- Answer: Enterovirus 71 (EV71).
- Difference from Herpangina: "How is Herpangina different?"
- Answer: Herpangina has posterior pharyngeal ulcers ONLY with no limb rash.
Viva Points
- Palm and Sole Rash: Unusual distribution – most rashes spare palms/soles. Think HFMD, Syphilis, Rocky Mountain Spotted Fever, Infective Endocarditis.
- Onychomadesis: Nail shedding weeks later is benign and reversible.
- Dehydration: Most common reason for hospital admission. Painful ulcers → Child stops drinking.
Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists.