Chickenpox in Children

• Chickenpox occurs at all ages, especially in children, and can happen year-round, with outbreaks more common during cold weather.
• Chickenpox symptoms include fever, headache, body aches, fatigue, itching, and red rashes that later develop into clear blisters appearing all over the body.
• Vaccination can protect against chickenpox for up to 20 years, with 85% effectiveness in prevention and over 95% effectiveness in preventing severe symptoms.

Understanding Chickenpox

Chickenpox or Chickenpox is caused by the Varicella virus, which spreads easily and is also the cause of shingles. It transmits through direct contact with chickenpox blisters and via inhaling respiratory droplets contaminated with the virus. Sharing items with infected patients can also spread the disease. It is common in children and outbreaks peak during cold weather. Adults with weakened immunity can also contract chickenpox, often experiencing more severe symptoms. However, chickenpox can be prevented by vaccination.

Symptoms of Chickenpox

After exposure, symptoms appear within 10 to 21 days, including fever, headache, body aches, fatigue, itching, and red rashes that become clear blisters all over the body. The blisters itch and then transform into watery vesicles, which later scab over and eventually fall off.

Possible Complications of Chickenpox

Usually, chickenpox resolves without scarring. However, secondary bacterial infections can cause blisters to become pus-filled and leave wounds. After chickenpox infection, there is a risk of developing shingles later.

Causes of Chickenpox in Children

Chickenpox occurs when children come into close contact with infected individuals or stay in crowded places, increasing the risk of transmission.

Diagnosis of Chickenpox

Doctors diagnose chickenpox through physical examination and may order blood tests to check immunity levels if symptoms are unclear.

Treatment of Chickenpox

Patients should rest, stay hydrated, bathe to maintain cleanliness, and keep nails short to avoid scratching blisters. Calamine lotion can relieve itching, and maintaining cleanliness of surroundings reduces infection risk.

Chickenpox Vaccine (Varicella Vaccine)

Studies in Japan show the vaccine prevents chickenpox 70–85% of the time for up to 20 years and prevents severe disease in over 95% of cases.

In Thailand, there are single vaccines (Varicella Zoster Virus: VZV) protecting only against chickenpox, and combination vaccines (Mumps Measles Rubella Varicella Vaccine) that protect against measles, mumps, rubella, and chickenpox in one dose.

Who Should Receive the Chickenpox Vaccine

• Children aged 1 year and older should receive two doses.

The first dose can be given starting at 1 year old.
(The second dose is given 6 months after the first.)

• Children who have never had chickenpox or are under 12 years old.

(Should receive two doses of the vaccine)chickenpoxwith at least 3 months between doses.)

• Children aged 13 years and older

(Should receive two doses of the vaccine)chickenpoxwith at least 1 month between doses.)

• Caregivers of chickenpox patients

Preparation Before Getting the Chickenpox Vaccine

• Individuals with a history of chickenpox, immune deficiencies, tuberculosis, or cancer should inform their doctor before vaccination.
• If experiencing fever or acute illness, postpone vaccination until 7 days after recovery.

Note

• The chickenpox vaccine can be given any time during the year and can be administered alongside other vaccines.
• A medical examination by a doctor is required before vaccination.

Who Should Not Receive the Chickenpox Vaccine

• Patients taking immunosuppressive medications.
• Patients with immune deficiencies.
• Patients who have received blood transfusions.

Benefits of the Chickenpox Vaccine

• Vaccination reduces the chance of contracting the Varicella virus.
• It also reduces the chance of developing shingles.

After Receiving the Chickenpox Vaccine

• Sit and rest for about 15 minutes to prevent fainting.
• If feeling dizzy, notify a doctor immediately.
• If pain or swelling occurs at the injection site, apply ice to relieve symptoms.
• A rash similar to chickenpox may appear around the injection site but will resolve on its own.

Information provided by Dr. Wiriyaporn Chanratchakool, Pediatric Infectious Disease SpecialistSamitivej International Children's Hospital