Definition

Chickenpox, or varicella zoster, is a highly contagious infection caused by the Varicella zoster virus. It is characterized by red spots that develop into small, fluid-filled blisters that can be itchy and sometimes painful. Most people who get chickenpox develop lifelong immunity, although it is possible, though rare, to get it more than once. Chickenpox is easily transmitted from an infected person to those who have never had the disease or been vaccinated against it.

The highest incidence of chickenpox is found in children aged 4-10 years, although it can also occur in adults. The infection rate of chickenpox is estimated to be around 90%, making it a highly contagious disease. In adults, chickenpox can leave deeper and darker scars compared to when it occurs in children.

Various varicella vaccine brands are currently available in Indonesia to protect children and adults from chickenpox. These vaccines are safe and effective in preventing the infection and its potential complications.

Causes

Chickenpox is caused by the Varicella zoster virus (VZV). The virus spreads easily from an infected person to others who have never had chickenpox or been vaccinated. When someone has chickenpox, about 90% of people close to them who are not immune will also get the disease. The virus spreads primarily through direct contact with the infected person or through respiratory droplets from:

• Saliva
• Coughing
• Sneezing

An individual with chickenpox can spread the virus from 1-2 days before the rash appears until all the blisters have crusted over. Vaccinated individuals may have a milder rash that does not crust over and is no longer contagious after 24 hours without new rashes.

Besides causing chickenpox, VZV also causes herpes zoster (shingles). After causing chickenpox, the virus remains dormant in the body. Herpes zoster occurs when the dormant virus reactivates. A person with herpes zoster can spread the virus to someone who has never had chickenpox or been vaccinated. The virus spreads through direct contact with the fluid from shingles blisters or by inhaling virus particles from these blisters. People infected from herpes zoster will first develop chickenpox, not shingles.

Risk factor

Individuals who have never had chickenpox or been vaccinated are at risk for the disease. Factors that can increase the risk of infection include:

• Contact or exposure to someone with chickenpox
• Age under 12 years
• Adults living with children
• Spending extended time in schools or childcare facilities
• Weakened immune system due to illness or medication

If you have had a varicella infection before or have been vaccinated, your risk of contracting the disease is reduced.

Symptoms

Chickenpox symptoms typically appear around two weeks (ranging from 7 to 21 days) after exposure to the virus and usually last about 4 to 7 days. The classic symptom is a rash that turns into itchy, fluid-filled blisters. The rash usually follows three stages: red or pink spots, then fluid-filled blisters that break easily, and finally, crusts and scabs. Scratching the blisters can lead to bacterial infection.

Before the rash appears, flu-like symptoms may occur one to two days prior, including:

• Fever
• Fatigue
• Loss of appetite
• Headache

Diagnosis

Doctors typically diagnose chickenpox based on the characteristic rash. If there is uncertainty, varicella can be confirmed with laboratory tests, such as blood tests or a culture of blister fluid. It is important to inform your doctor if you or a family member has had chickenpox before and the timing of the first symptoms to aid in diagnosis and treatment.

Management

Treatment for chickenpox focuses on alleviating symptoms. Most cases are managed with self-care and specific medications. Patients are often advised to isolate at home to prevent spreading the virus.

Home Care

Parents of children with chickenpox should keep them home from school to avoid spreading the virus. Adult patients should also rest at home. Calamine lotion and cool baths with baking soda, uncooked oatmeal, or colloidal oatmeal can help relieve itching. Keeping nails short and avoiding scratching the rash are essential to easing symptoms and preventing skin infection.

Medications

Doctors may prescribe anti-itch powders, pain relievers like paracetamol, and over-the-counter medications. Aspirin is not recommended due to its association with Reye's syndrome in children with chickenpox. Antiviral medications are recommended for individuals at risk of serious complications, such as:

• Healthy individuals over 12 years old
• People with chronic skin or lung conditions
• Those on long-term salicylate or steroid therapy
• Pregnant women
• People with weakened immune systems

Antivirals are most effective within the first 24 hours of rash onset. These medications do not cure chickenpox but help reduce symptoms by inhibiting viral activity.

Complications

While rare in healthy individuals, chickenpox can cause complications such as eye infections, bacterial skin infections, and neurological issues. Those at higher risk include:

• Infants
• Adolescents
• Adults
• Pregnant women who may face risks such as congenital varicella syndrome in their unborn child

Serious complications of varicella that can occur are:

• Bacterial infections of the skin and soft tissues in children, including Group A Streptococcus bacterial infections
• Lung infections (pneumonia)
• Brain infections or swelling
• Bleeding
• Blood infections (sepsis)
• Dehydration

Some individuals develop severe complications from varicella that necessitate hospitalization. The most serious complication is death, though it is extremely rare due to the widespread vaccination program. When it does occur, it typically affects healthy children and adults who have not been vaccinated.

Prevention

The best way to prevent chickenpox is through vaccination. The varicella vaccine is safe and effective, significantly reducing the risk of severe illness. Most vaccinated individuals who contract the virus will have milder symptoms.

When to see a doctor?

Consult a doctor if you have been exposed to varicella zoster or herpes zoster and have not had chickenpox or been vaccinated, are pregnant, or have a weakened immune system. Seek medical advice if experiencing severe symptoms, such as high fever, persistent fever, intensely red and painful rash, difficulty waking up or behavior changes, trouble walking, neck stiffness, frequent vomiting, difficulty breathing, severe cough, or abdominal pain.

By understanding chickenpox's symptoms, risks, and preventive measures, you can take appropriate steps to protect yourself and others from this contagious disease.