Chickenpox FAQs

Chickenpox FAQs

Can chickenpox be prevented?

The best and most effective means of prevention is the chickenpox vaccine (varicella vaccine). To date it has prevented up to 90% of infections in children who have had the vaccine. Those who haven’t received the vaccine are not immune to the virus causing chickenpox and can get an infection at any stage. The vaccine is given in two shots, one around 12 to 15 months and another between the ages of 4 and 6. Catch-up doses of the vaccine are available for older children and adults who have not received a vaccine during early childhood.

The vaccine is recommended for all young children at least 12 months of age, who are in good health, as well as anyone who is generally healthy but hasn’t had or isn’t sure if they’ve had the vaccine during early childhood. Women who are planning to get pregnant should also ensure that they are either immune or receive the vaccine beforehand, this can be done through a simple blood test.

If a woman becomes pregnant and contracts the virus, the combination can be dangerous and lead to terrible complications during the gestation period. A doctor can best advise a woman about the most appropriate time to receive a vaccination before getting pregnant so as to prevent potential complications. If a woman is pregnant and contracts chickenpox, she may be given a shot of antibodies (immunoglobulin) or an antiviral medication to alleviate symptoms.

Those with a weak immune system should be well aware of anyone around them who may be infected with chickenpox, especially if they have not received a vaccination against the virus. If you find that you are exposed to the virus, talk to your doctor. You may be able to receive the vaccine and either prevent yourself from falling ill or only experience milder symptoms of an infection.

What is the chickenpox (varicella) vaccine?

Varicella vaccine in vial with syringe and medicines

The vaccine was developed from a live, but weakened varicella-zoster virus (VZV) so as to make so as to make an infection with chickenpox less virulent or destructive on the body. Generally, the vaccine is incapable of causing an infection, but it can still stimulate a response in the immune system (this affords protection from falling ill from the virus). As little as 2% of vaccinated children may develop a mild case of chickenpox, with just a handful of blisters.

A vaccine is deemed necessary by medical professionals even for those who do not fall into high-risk categories (such as infants, adults and those with impaired immune systems) as there is no way to predict who will fall into a small percentage of people who’ll experience complications of a severe or life-threatening nature. The other main reason for the vaccine is the contagious nature of the virus.

Most will agree that anyone who has had chickenpox (whether they’ve been vaccinated against it or not) should not require a vaccine. Typically, once you’ve had an infection, you are immune. The vaccine is generally available as a combination for protection against other conditions, namely measles, German measles (rubella), mumps and chickenpox (varicella). This vaccine is known as MMRV.

What are the chickenpox vaccine side effects?

The chickenpox (varicella) vaccine, like any other medication is not without associated side-effects. Any that are to be expected, are relatively mild though. Once you receive the vaccine you may experience temporary inflammation (redness) and swelling at the injection site, and a little pain. Some may even develop a little bit of a mild rash or low-grade fever. All side effects typically clear in a short period of time and aren’t to be too alarmed about.

A very small percentage of people may experience more severe side effects (such as seizures, Pneumonia, balance problems or a brain infection) or even an allergic reaction (anaphylaxis). If you are concerned about any associated side-effects, see your medical professional as soon as possible to be on the safe side.

It can happen that a vaccine is administered when a person is moderately or more seriously ill with another condition. Generally, a medical professional will not administer a vaccine shot unless a person is generally healthy as this can bring about health complications and severe side-effects.

Individuals who will not likely be recommended to receive a vaccination include:

  • Women who are pregnant
  • Those who have a known allergy to gelatin (gelatine) or neomycin (an antibiotic)
  • Those who are being treated with high doses of steroids, radiation or chemotherapy
  • Those who have received a blood transfusion or other blood products within 5 months

When should an adult be vaccinated against chickenpox?

If you’ve never had chickenpox or been vaccinated, your doctor can advise whether or not you can receive a vaccination, following a quick consultation. If it is determined that it is safe for you, you are likely to receive 2 doses, at 4 weeks apart. Thereafter the likelihood of falling ill after being exposed to someone with the virus is dramatically reduced (the vaccine is estimated to be between 70% to 90% effective).

If you do happen to be exposed to someone with chickenpox and fall ill, symptoms will be significantly milder than if you hadn’t received a vaccine.

Can you get chickenpox during pregnancy?

It is possible to contract chickenpox during pregnancy, and it isn’t something to be taken lightly. If you are pregnant and fall ill with the virus, both you and your developing baby are exposed to serious health concerns, such as varicella pneumonia.

Complications affecting a developing baby depends largely on the timing of infection. If infection occurs:

  • During the first 20 weeks of pregnancy: A baby is at risk of serious birth defects (congenital varicella syndrome) which include scarring of the skin, underdeveloped limbs (arms and legs), eye inflammation, and impaired brain development. Risk is especially high between weeks 8 and 20.
  • At least 48 hours before birth (delivery of the baby): A baby may be born with neonatal varicella, which is a potentially life-threatening infection. A baby may be treated with antiviral medications once born, as will a mother who delivers with a chickenpox infection.

A woman who is not immune and intends falling pregnant should consult her doctor. If she is exposed to the virus during pregnancy, a doctor will recommend an injection of antibodies or antiviral medication so as to provide the best means of reducing the severity of falling ill. There is no absolute certainty that an immune globulin shot won’t have any side-effects on a developing baby either. The best means of protection is to have a vaccination at least 3 months before falling pregnant to ensure immunity. Blood tests can confirm immunity, and also determine whether you’ve had a vaccine (if you are unsure whether you have or have not been vaccinated).

Are you more vulnerable to shingles when you’ve had chickenpox?

Shingles - illustration showing a viral infection with skin blisters and sores.The varicella-zoster virus (VZV) can also lead to falling ill with a condition known as shingles (herpes zoster). Visible symptoms of shingles include a rather painful skin rash (sometimes with blisters), known as postherpetic neuralgia, which typically develops in a strip / band along a small area on one side of the body or even the facial area. The rash and blisters can be painful and the pain typically lasts even after marks and inflammation clear (this is known as post herpetic neuralgia).

It is common for the chickenpox virus to remain in a person’s nerve cells following an infection, becoming dormant, and reactivating again at some stage during a person’s lifetime. When this happens, it can resurface as a shingles infection. This typically happens to older adults or those who have weakened or impaired immune systems.


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