🤒 Chickenpox vs HFMD vs Roseola Rash Differential Simulator

What Each Rash Looks Like Up Close

Placeholder: lesion shape and stage differ across the three diseases.

• Vesicle: Chickenpox (Dewdrop-on-rose-petal look)
• Oval blister: HFMD (Grey vesicle, red halo)
• Macule: Roseola (Flat, blanching, rose-pink)
• Polymorphism: Key clue (Chickenpox shows all stages at once)

Lesion morphology placeholder

Placeholder text describing vesicle, pustule, and macule differences briefly.

Where the Rash Shows Up on the Body

Placeholder: distribution site is a fast visual differentiator.

• Centripetal: Chickenpox (Trunk-heavy, spreads outward)
• Acral + oral: HFMD (Palms, soles, mouth)
• Truncal: Roseola (Trunk and neck, spares face)
• Palms/soles: Key clue (Distinctive for HFMD only)

Distribution mapping placeholder

Placeholder text about mapping rash density across body regions.

When the Rash Appears Relative to Fever

Placeholder: timing sequence narrows the diagnosis quickly.

• Day 0–2: Chickenpox (Fever and rash concurrent)
• Day 1–3: HFMD (Mild fever, then rash)
• Day 3–5: Roseola (Rash follows fever break)
• Defervescence: Key clue (Roseola rash starts as fever drops)

Timeline correlation placeholder

Placeholder text explaining fever curve versus rash onset timing.

Symptoms That Travel With Each Rash

Placeholder: accompanying signs help confirm the diagnosis.

• Pruritus: Chickenpox (Intense itching, malaise)
• Oral ulcers: HFMD (Sore throat, poor feeding)
• High fever: Roseola (Irritability, febrile seizure risk)
• Itch vs pain: Key clue (Chickenpox itches, HFMD hurts)

Symptom cluster placeholder

Placeholder text summarizing companion symptoms per disease.

Putting the Clues Together

Placeholder: combine appearance, site, and timing for a call.

• Vesicle + trunk: Chickenpox call (All stages present)
• Hand/foot/mouth: HFMD call (Oral ulcers plus acral rash)
• Post-fever rash: Roseola call (Well-appearing child)
• ~85%: Overall accuracy (Placeholder composite confidence)

Differential summary placeholder

Placeholder text tying the three-disease comparison together.

Placeholder key insight: combine rash shape, site, and fever timing.