Chickenpox, also known as varicella, is a highly contagious viral infection that mainly affects children but can occur at any age. It usually begins with fever, fatigue, and body aches, followed by an itchy red rash that develops into fluid-filled blisters and later forms scabs. The virus spreads easily through close contact with an infected person or by inhaling droplets released during coughing or sneezing. While most cases are mild, serious complications can occur in newborns, pregnant individuals, and people with weakened immune systems.
Thanks to widespread vaccination, chickenpox is now far less common than in the past. Even after recovery, the virus remains dormant in the body and may reactivate later in life as shingles, which causes a painful skin rash. To reduce this risk, a shingles vaccine is recommended for adults over 50 years of age and for younger adults with compromised immunity.
Vaccination remains the most effective way to prevent both chickenpox and its long-term complications, helping protect individuals and communities from serious illness.
Symptoms of Chickenpox:
Chickenpox symptoms usually begin 10 to 21 days after exposure to the varicella-zoster virus. The illness often starts with mild, flu-like signs before the rash appears. These early symptoms may include:
- Fever
- Poor appetite
- Headache
- Muscle aches
- Fatigue and a general feeling of discomfort
Within one or two days, the characteristic rash develops. The rash progresses through three main stages:
- Papules: Small, red, raised spots that appear over several days.
- Vesicles: These spots turn into itchy, fluid-filled blisters that may burst.
- Scabs: The blisters dry out, forming crusts that eventually fall off as the skin heals.
Because new spots continue to appear, a person may have all three stages at the same time. The rash usually lasts 5 to 10 days.
A person with chickenpox can spread the virus up to two days before the rash appears and remains contagious until all blisters have dried and crusted over.
In most healthy children, chickenpox is mild. However, in some cases, the rash can spread over the entire body, including the scalp, mouth, throat, eyes, and genital areas. Blisters inside the mouth or throat may cause pain while eating or drinking.
Additional symptoms may include intense itching, dehydration, irritability in young children, and trouble sleeping. In adolescents, adults, pregnant women, and people with weak immune systems, symptoms can be more severe and may lead to complications.
When to Seek Medical Advice for Chickenpox?
If you believe that you or your child may have chickenpox, contact a healthcare professional by phone before visiting the clinic. Doctors can often identify chickenpox by examining the rash and reviewing other symptoms. In some cases, antiviral medicines or treatments may be needed to reduce complications. Calling ahead also helps protect others from possible exposure.
Be sure to inform your doctor immediately if:
- The rash spreads to one or both eyes.
- The skin around the rash becomes very red, warm, swollen, or painful, which may indicate a bacterial infection.
- Severe symptoms develop, such as dizziness, confusion, rapid heartbeat, breathing difficulty, muscle weakness, worsening cough, repeated vomiting, stiff neck, or a fever above 102°F (38.9°C).
- You live with people who have never had chickenpox and are not vaccinated.
- A pregnant person is in your household.
- Someone at home has a weakened immune system due to illness or medication.
Prompt medical guidance can help prevent complications and protect vulnerable individuals from serious infection.
What Causes Chickenpox?
Chickenpox is caused by the varicella-zoster virus (VZV), a highly contagious virus that spreads easily from person to person. Infection can occur through direct contact with the fluid from chickenpox blisters, inhaling tiny droplets released when an infected person coughs or sneezes, or by touching contaminated objects and then touching the face, mouth, or eyes.
A person with chickenpox can spread the virus one to two days before the rash appears and remains contagious until all blisters have dried and formed scabs. This makes the disease difficult to control in schools, households, and crowded places.
Once the body recovers, the virus does not completely leave the system. Instead, it stays inactive in nerve tissues. Years later, it may reactivate as shingles (herpes zoster), causing a painful, localized rash, usually on one side of the body.
Factors that increase the risk of developing shingles include aging, stress, weakened immunity, and certain medical treatments.
To reduce this risk, healthcare professionals recommend the Shingrix vaccine for adults over 50 years of age. It is given in two doses, spaced 2 to 6 months apart, and provides strong protection against shingles and its complications.
Vaccination against chickenpox in childhood remains the most effective way to prevent the initial infection and reduce future health risks.
Risk Factors for Chickenpox:
People who have never had chickenpox or have not received the vaccine are highly likely to become infected after close contact with an infected person. Chickenpox spreads easily, especially in households, schools, and crowded environments.
Certain groups are more likely to develop severe illness or complications, including:
- Infants under one year of age: Their immune systems are still developing, making it harder to fight the virus.
- Adults over 20 years: Symptoms tend to be more intense and complications are more common.
- Pregnant individuals: Infection can increase health risks for both the mother and the unborn baby.
- People with weakened immunity: This includes those with chronic illnesses, cancer, HIV, or those taking immune-suppressing medications.
In these high-risk groups, chickenpox may lead to pneumonia, skin infections, or nervous system problems. Vaccination remains the most effective way to lower the risk of infection and serious complications.
How Is Chickenpox Diagnosed?
Chickenpox is usually diagnosed based on its distinctive itchy rash and accompanying symptoms such as fever, fatigue, and headache. In most cases, a healthcare provider can confirm the condition through a physical examination and medical history alone.
If the diagnosis is unclear, laboratory tests may be recommended, including:
- PCR test: A small sample of fluid from a blister is tested to detect the varicella-zoster virus.
- Blood tests: Used to check for antibodies or signs of recent infection.
- Viral culture: Blister fluid is grown in a laboratory to identify the virus.
To ensure an accurate diagnosis, doctors may also rule out other illnesses that cause similar rashes, such as:
- Shingles
- Other viral infections like herpes or enteroviruses
- Allergic drug reactions
- Erythema multiforme
- Rickettsialpox
- Scabies
- Rare poxvirus infections such as mpox, cowpox, or smallpox
- Impetigo
- Insect bites
- Measles
- Rubella
- Hand, foot, and mouth disease
Accurate diagnosis is important because treatment and infection control measures vary depending on the cause of the rash. Early confirmation also helps prevent spreading the virus to others.
Chickenpox Treatment:
Chickenpox usually resolves on its own within one to two weeks, and treatment mainly focuses on relieving itching, fever, and discomfort.
Ways to Reduce Itching and Irritation:
You can ease symptoms by:
- Staying in a cool environment or using cool compresses on the skin
- Taking lukewarm baths with baking soda or plain oatmeal
- Applying calamine lotion to the blisters
- Using oral antihistamines such as cetirizine or diphenhydramine (as advised by a doctor)
Pain and Fever Relief:
Non-aspirin fever and pain relievers, such as acetaminophen, are recommended. Parents should avoid giving children ibuprofen unless advised by a healthcare provider.
Important Warning About Aspirin:
Children should never be given aspirin for chickenpox. Aspirin use during viral infections can lead to Reye’s syndrome, a rare but life-threatening condition that affects the brain and liver.
Antiviral and Special Treatments:
Doctors may prescribe antiviral medicines like acyclovir for:
- People with severe infections
- Individuals with weakened immune systems
- Adults and high-risk patients
These medicines help shorten the illness and lower the risk of complications.
For people who cannot receive the vaccine and are at high risk, doctors may recommend varicella-zoster immune globulin to reduce disease severity after exposure.
Complications of Chickenpox:
Chickenpox is usually mild in children but can become serious in:
- Infants under one year
- People older than 12 years
- Pregnant individuals
- Those with weakened immune systems
Common Complications:
- Bacterial skin infections
- Dehydration
- Pneumonia
Children:
Children are most likely to develop skin infections from scratching and may become dehydrated if they refuse fluids.
Adults:
Adults face a higher risk of pneumonia and may develop rare but serious conditions such as:
- Loss of muscle coordination
- Brain inflammation
- Bleeding disorders
- Bloodstream infections or bone infections
Pregnancy Risks:
Pregnant individuals with chickenpox have a higher chance of pneumonia. If infection occurs early in pregnancy, the baby may develop birth defects such as limb abnormalities, vision problems, brain damage, or low birth weight.
Chickenpox Vaccine:
Before the vaccine was introduced, chickenpox affected millions of people each year. Vaccination has dramatically reduced cases worldwide.
Health authorities recommend two doses of the chickenpox vaccine for anyone who has not had the disease or previous vaccination.
Vaccination Schedule:
- First dose: 12–15 months of age
- Second dose: 4–6 years of age (or at least three months after the first dose)
Who Else Should Be Vaccinated?
Vaccination is especially important for:
- Teachers and childcare workers
- Healthcare workers
- Caregivers of immunocompromised individuals
- Military personnel
- International travelers
- People in crowded living environments
- Teens and adults living with young children
- Individuals who are planning pregnancy
Vaccination not only protects the individual but also helps prevent community outbreaks.
