Chickenpox (Varicella) Vaccine: What You Should Know

Chickenpox, also known as varicella, is a common viral disease that infects both children and adults. Fortunately, there is a safe and effective way to protect against this virus and its associated complications.

What Is Chickenpox?

Chickenpox, also known as varicella, is a highly contagious viral infection that is caused by the varicella-zoster virus. It is primarily characterised by vesicular skin lesions that cause an itchy rash, fever, fatigue, and other symptoms.

Chickenpox is most prevalent in children under 10 years of age. Adults can be infected with this disease. Unfortunately, when infected, adults experience more severe symptoms and complications than children.

The same virus that causes chickenpox also causes shingles. The varicella virus stays inactive in the body after a person recovers from chickenpox. The virus can reactivate many years later causing shingles.

One of the characteristics features of shingles are painful and itchy rash that occur over one side of the face or body. People can experience pain or tingling sensation at the area where the rashes appear. 

How Is Chickenpox Transmitted in Children?

Chickenpox is highly contagious and can be transmitted through coughing or sneezing. However, for the most part, the chickenpox virus is spread by direct contact with an infected person’s skin or mucous membrane (such as the eyes or nose). 

This means that if a child touches their own mouth or nose whilst infected, then someone else could get it by simply touching the child’s hand. By the same token, one may be infected with chickenpox from direct contact with a sore from an infected person. Patients may also contaminate solid surfaces like televisions, desks, or beds by touching them after being exposed to the virus.

Generally, the virus can stay alive for about two hours on surfaces like door handles and doorknobs where there has been direct contact with an infected person’s hand.

What Are the Symptoms of Chickenpox?

On average, it takes approximately 10 to 21 days to develop symptoms after being exposed to an infected person.

The main recognisable symptom of chickenpox is itchy, fluid filled blisters called vesicles, that appear on the skin. The rash usually begins on the face and then spreads over the body.

These vesicular red spots are commonly found on the face, backside, armpits, and groin area as well as other locations such as under breasts or around genitals where there is less clothing coverage for protection.

A mild case of chickenpox usually lasts for five to seven days. Chickenpox is contagious from the first day before a rash appears until all sores have crusted over—usually seven days after the first noticeable symptoms. 

Other symptoms include fever, fatigue, loss of appetite, and headache.

In more severe cases, patients may experience pneumonia, inflammation of the blood vessels, brain swelling, and infections of the bloodstream, bone, or joints. 

Are There Complications of Chickenpox?

Chickenpox is a common childhood disease that usually heals without any complications. In rare cases, however, it may lead to serious complications in babies, pregnant mothers, adolescent and adults and people with weak immune system.

The most common complications of chickenpox are pneumonia (lung infection), encephalitis (swelling of the brain) that may lead to seizures and brain damage, and bacterial skin infections. 

How Is Chickenpox Treated in Children?

If your child has chickenpox, it is important to treat the symptoms. Your doctor may prescribe medications like:

• Calamine lotion or antihistamines (for itching)
• Acetaminophen for fever control

Nonetheless, most chickenpox cases in otherwise healthy children are usually treated with sufficient bed rest, fluid consumption, and control of fever. 

However, they should not receive aspirin due to the possible subsequent risk of Reye’s Syndrome. In some instances, antiviral drugs can be taken in serious cases, depending on the extent of the infection, the patient’s age and health and the timing of the treatment.

What Is Chickenpox (Varicella) Vaccine?

The chickenpox vaccine (also called varicella) is a live attenuated virus vaccine that is given in two doses. A live attenuated virus is essentially a disease-producing virus that is modified, or weakened in a lab to produce an organism that delivers immunity in the body without causing illness.

• Chickenpox vaccine’s first dose is given between 12 and 15 months of age, usually as a single injection.
• Chickenpox vaccine’s second dose can be given within a minimum of three months interval from the first dose.

The vaccine is highly effective in protecting against chickenpox for people who are not immune to the disease due to previous infection or vaccination. It also helps to reduce the severity of symptoms and associated complications if a person does become infected with the virus. 

How Does the Chickenpox Vaccine Work?

Immunisation protects your child against chickenpox and helps protect others because someone who is vaccinated is less likely to spread infection. 

In practice, the chickenpox vaccine is administered as a shot in the fatty tissue of one’s upper arm or thigh.

For parents who want their children to get the chickenpox vaccine together with the MMR (measles, mumps, and rubella) vaccine, there is one vaccine which has both vaccines in one shot - MMRV (mumps, measles, rubella, and varicella). This vaccine can be taken at one year old and above.

What Is the Effectiveness of the Chickenpox Vaccine?

Real world studies reported the effectiveness of a two-dose varicella vaccine ranges between 84% to 98%. (Peter Wutzler, Paolo Bonani et al. Varicella vaccination - the global experience. Expert Rev Vaccines. 2017 Aug; 16(8): 833–843)

The chickenpox vaccine is a safe and effective way to protect against the varicella-zoster virus and its associated complications. 

According to the CDC, people vaccinated against chickenpox maintain antibodies for at least 10 to 20 years after childhood vaccination.

Receiving the vaccine may help to reduce the severity of symptoms if a person does become infected with the virus, as well as reduce the risk of serious complications. It can also help to reduce the spread of the virus to those who are not vaccinated. 

Therefore, it is important for children to receive the chickenpox vaccine to protect themselves and others from this highly contagious virus. Overall, getting the varicella vaccine is far safer than getting chickenpox disease.

Although extremely rare, some individuals may get infected even after immunisation. However, the illness will be milder than if they had not been vaccinated, and they will recover faster.

What Are the Side Effects of Chickenpox Vaccine?

The vaccine is safe and effective but may have some minor side effects. The most common are redness or swelling at the injection site, fever, and headache. Some people may have a mild rash that lasts one to two days after receiving the shot.

Though rarely, more serious reactions include pneumonia, brain infection, seizures often associated with fever and allergic reactions like anaphylaxis. 

To reduce the occurrence of side effects, inform your vaccination provider if the child receiving the vaccine:

• Had allergic reaction after a previous dose of varicella vaccine, or any severe, life-threatening allergies.
• Previously received other vaccines in the past 4 weeks.
• Has tuberculosis.
• Has a weakened immune system or has a parent or sibling with a history of hereditary or congenital immune system problems.
• Is taking salicylates (like aspirin). 
• Recently had a blood transfusion.

Make an Appointment at Pantai Hospitals

All things considered, the vaccine is the most effective way to protect your child from the chickenpox disease. It can provide immunity to the virus and help prevent potential complications and discomfort from the disease. Overall, it is safe, proven effective and has minimal side effects.

Get in touch with us to book an appointment today for a consultation, or visit our Paediatric Care Department at your nearest Pantai Hospital.

Pantai Hospitals have been accredited by the Malaysian Society for Quality in Health (MSQH) for its commitment to patient safety and service quality.

This article has been medically reviewed by Consultant Paediatrician and Neonatologist, Dr Livia Chow Huey Ling.