Disease Description (Causes and Symptoms)

Cause: Mainly an infection caused by enteroviruses. The most common causes are coxsackievirus group A (especially A16) and enterovirus 71 (EV‑71). It is transmitted through droplets (respiratory secretions), vesicle fluid, and feces.
Pathophysiology: After multiplying in the mucosa (oral pharynx), the virus spreads through the bloodstream and forms vesicles and ulcers on the skin of the hands and feet and the oral mucosa. Rarely, EV‑71 and other viruses may affect the central nervous system (meningitis·encephalitis) or the cardiovascular system (acute worsening of cardiopulmonary function).
Main symptoms: Fever, malaise, decreased appetite → oral pain (oral ulcers, difficulty swallowing), rash on the hands, feet, buttocks, etc. (small vesicles or erythema), headache, and localized pain (at the blister site). Children are at high risk of dehydration.

Treatment Methods

Basic principle: Most cases recover with symptom relief (supportive treatment). No specific antiviral medication is recommended as standard treatment.
Drug treatment/supportive treatment:
- Antipyretic analgesics: acetaminophen (Tylenol), ibuprofen (as directed by a doctor). Adjust the dosage based on body weight.
- Relief of oral pain: Relieve pain with lukewarm salt-water gargles and soft or cold foods (ice pops). For young infants, topical analgesics may be used under a doctor's prescription (subject to age and medication restrictions).
- Fluid replacement: If oral intake is insufficient, hospitalization and intravenous fluids may be required.
In severe cases (neurological or cardiopulmonary symptoms):
- Immediate hospitalization and pediatric intensive care (neurological symptoms: repeated vomiting, altered consciousness, seizures; signs of cardiopulmonary failure, etc.).
- Intensive care (respiratory and circulatory support); if necessary, intensive treatment such as high-dose immunoglobulin (IVIG) may be considered, depending on the situation and the judgment of a pediatric specialist.
Contraindications/precautions:
- Antibiotics must not be administered indiscriminately because this is a viral disease (only when a secondary bacterial infection has been confirmed).
- Caution is required because insufficient fluid intake can lead to dehydration and shock.

What to bring:
- A list of currently used medications (prescription and nonprescription) and a history of allergies
- The time fever and symptoms began, and temperature records (by time of day if possible)
- Records of food/fluid intake and the number of urinations and bowel movements
- Photos of the affected areas (mouth, hands, feet, etc.) on a mobile phone
- Contact history: whether anyone else has the same symptoms (family members, daycare, etc.)
- A history of previous hospitalization or severe infection (especially neurological disease)
Information to show the doctor at the outpatient visit:
- Duration of fever and maximum temperature
- Difficulty swallowing, whether vomiting occurs, and whether drowsiness, altered consciousness, or seizures are present
- Whether urine output or fluid intake has sharply decreased

What is the appropriate dosage and administration interval for this medication (antipyretic·analgesic)? What are its side effects?
How do you determine whether hospitalization is necessary? What symptoms mean that we should go to the emergency room immediately?
How long after recovery is there a possibility of transmitting the infection to others? etc.

My child is barely drinking water and has decreased urine output. Is hospitalization necessary now?
If vomiting, a severe headache, or altered consciousness develops after a fever, what emergency measures should be taken immediately, and what tests will the hospital perform?

Additional Precautions

Basic prevention includes handwashing, disinfecting surfaces, and minimizing contact with people who have symptoms.
The course is generally favorable, but EV‑71-associated infection can rarely cause severe complications (meningitis·encephalitis·cardiopulmonary failure). Therefore, visit a medical institution immediately if any of the severe symptoms mentioned above occur.