Varicella (chickenpox) vaccine

Pick any adult from the crowd. The likelihood that he had chickenpox is very high. But those chances are changing now that we have a varicella vaccine.

What is the chickenpox vaccine?

The chickenpox vaccine is a vaccine that can prevent chickenpox in almost anyone who gets the vaccine. It is also called the varicella vaccine because chickenpox is caused by the varicella-zoster virus. The vaccine is made from a live but weakened or attenuated virus.

Attenuated viruses are less virulent than normal viruses. Although the virus in the varicella vaccine usually cannot cause illness, it does stimulate the body's immune system to respond. It is this reaction that gives a person who has had a varicella vaccine immunity or protection from the disease.

Why do people need a chickenpox vaccine?

In most cases, chickenpox is relatively mild and resolves in five to ten days. But it can be very serious, even fatal, in a small percentage of people.

The risk of serious and life-threatening complications is higher in infants, the elderly, and people with weakened immune systems. But anyone can develop serious complications, and it is impossible to predict who will develop them.

There is another reason to get the chickenpox vaccine. The disease is highly contagious and, without a vaccine, can be transmitted through direct contact or airborne droplets when sneezing or coughing. Also, someone can become infected by coming into contact with the fluid from the chickenpox blisters. For this reason, children with chickenpox should be kept away from school or daycare for about a week or more until all blisters have dried and crusted over. The disease causes an itchy rash that usually forms 200 to 500 blisters all over the body, headaches, coughing, and irritability. Thus, even if the illness is mild, it still means 5-10 days of discomfort.

Is it necessary to vaccinate children against chickenpox?

In most countries, children entering kindergartens, schools, and even colleges and universities must show evidence of immunity to varicella, either as a result of a past illness or as a result of varicella vaccination.

Who should get the chickenpox vaccine?

The chickenpox vaccine is recommended for all children under 13 who have not had chickenpox. It is also recommended for all unvaccinated adolescents and adults who have not had chickenpox.

If you have had chickenpox, you do not need to be vaccinated.

How many doses of chickenpox vaccine are needed?

The chickenpox vaccine is given in two doses. Your child should have their first vaccination between 12 and 18 months of age. The second injection should be given between 4 and 6 years of age. Older children and adults should receive two injections, four to eight weeks apart between the first and second injections.

Are there side effects associated with the chickenpox vaccine?

All medicines have potential side effects. But the side effects associated with the varicella vaccine are usually minor. The most common are pain, redness, or swelling at the injection site. A small percentage of people develop a mild rash, usually around the impact site. Serious side effects are very rare.

Are there people who should not get the chickenpox vaccine?

Anyone who is moderately or severely ill at the time of a scheduled varicella vaccination should wait until the illness has cleared up before being vaccinated. Also, anyone who had an allergic reaction to the first shot should not get the second shot.

Other people who should not get vaccinated include:

Pregnant women, because the vaccine's effect on the fetus is not known
Anyone allergic to gelatin; a gelatin-free version of the varicella vaccine is available.
Anyone allergic to neomycin
Anyone with an immune system disease
Anyone receiving high doses of steroids
Anyone being treated for cancer with X-rays, drugs, or chemotherapy
Anyone who had a transfusion or received blood products within five months prior to the shot.

If the varicella-zoster vaccine virus is alive, can it cause chickenpox?

About 2% of vaccinated children get very mild chickenpox, usually with no more than five to six blisters.

It is also possible that a person who has been vaccinated against chickenpox will develop chickenpox later in life. When this happens, the illness is almost always milder and recovery is faster than in unvaccinated people. The lesions also may not have the same crusting pattern, and the blisters may not contain as much fluid when a vaccinated patient develops the virus.

But it is important to keep in mind that up to 90% of vaccinated people do not get chickenpox.