Chickenpox: Now Preventable
and childhood. They go together. But they don't have to anymore, thanks
to the chickenpox vaccine.
Chickenpox or varicella is a very contagious disease affecting 95
percent of the American population by age 18. Four million cases occur
each year in the United States, mainly in children ages five to nine.
Typically, chickenpox means worry and lost workdays for parents.
Children feel sick. They have fever. They itch. They miss school and
But did you know that
chickenpox can lead to hospitalization and, in rare instances, even
death? Chickenpox is especially risky for children with certain diseases,
such as leukemia. However, it can be serious or fatal in healthy children
too. And there is no way to know beforehand how chickenpox will affect
your healthy child.
In March 1995, following
more than a decade of development and testing, the U.S. Food and Drug
Administration (FDA) approved the country's first chickenpox vaccine
for use in children and adults who have not had chickenpox . The
FDA concluded that the vaccine is safe and effective. Since then,
the American Academy of Pediatrics, Centers for Disease Control and
Prevention and American Academy of Family Practitioners have all recommended
the chickenpox vaccine for routine use in children and adults who
have not had chickenpox. Furthermore, they have added the chickenpox
vaccine to the existing, routine schedule of vaccines recommended
for all healthy children (e.g., measles-mumps-rubella vaccine).
Chickenpox Vaccine: Questions & Answers
- While millions of Americans have been vaccinated against chickenpox
to date, some questions about the vaccine persist. Is the vaccine
safe? How long will the immunity (protection) provided by the vaccine
- Questions such as these are common to all new vaccines. Foolproof
answers to these questions will require decades more experience
with the varicella vaccine. But they are answered here to the extent
possible using data from the U.S. and more than 20 years experience
with the vaccine in Japan.
- We hope that this information will help encourage you and your
doctor to follow the expert recommendations described in the previous
WHY SHOULD CHICKENPOX BE PREVENTED?
Despite its reputation as a mild childhood illness, chickenpox is
a significant disease. At best, it can cause fever, discomfort, loss
of appetite, headache and skin lesions (vesicles or blisters), which
can leave scars. At its worst, it can lead to hospitalization and,
in rare instances, death.
Bacterial skin infections are the most common chickenpox-related
complication, and they are increasing in number and severity. Other
complications include inflammation of the brain (encephalitis) and
pneumonia, although these are rare in otherwise healthy people.
According to the Centers for Disease Control and Prevention, each
year in the U.S., chickenpox complications result in: the hospitalization
of nearly 11,000 individuals, the majority of whom are otherwise healthy,
and two-thirds of whom are children; and nearly 105 deaths.
Furthermore, it is believed that more chickenpox-related deaths occur
than are reported. Deaths that occur from a chickenpox complication
-- for example, a bacterial infection that spreads to the bloodstream
-- are sometimes reported without mention of chickenpox as the underlying
IS THE VACCINE SAFE AND EFFECTIVE?
Experience and research to date have shown the chickenpox vaccine
to be safe and effective. The U.S. vaccine is derived from the Oka
strain vaccine. The Oka strain vaccine was developed in Japan more
than 20 years ago and has since been used successfully and safely
there and in several other parts of the world.
The vaccine was studied in the U.S. for more than a decade. Since
its U.S. approval, side effects have been reported in a small percentage
of vaccinated children. They are generally mild and include: pain,
redness or a slight rash at the injection site, mild fever and fussiness.
There are certain groups of people, such as children with a weakened
immune system or pregnant women, who should not receive the chickenpox
vaccine . You should speak to your doctor to determine whether
you or your child fall into any of the categories of individuals who
should not be vaccinated against chickenpox.
HOW LONG WILL THE VACCINE PROTECT MY CHILD AGAINST CHICKENPOX?
The length of protection/immunity that any new vaccine provides is
never known when it is first introduced. However, more than 20 years
experience and research indicate that varicella vaccine protection
lasts at least 20 years, and probably more.
The duration of immunity continues to be studied. If a booster is
recommended at a future date, both the medical community and the general
public will be informed.
ISN'T IT TRUE THAT A VACCINATED CHILD CAN STILL GET CHICKENPOX?
There have been a few reported cases of vaccinated children coming
down with chickenpox after exposure to it. It is important to note,
however, that these few cases have been very mild (sometimes with
only one or two blisters) and have lasted only a short time .
Interestingly enough, studies show that when vaccinated individuals
come into contact with a case of chickenpox, their immunity to chickenpox
is often increased or boosted.
HOW DOES THE VACCINE AFFECT ONE'S CHANCES OF DEVELOPING SHINGLES
LATER IN LIFE?
The varicella-zoster virus or VZV, which causes chickenpox, remains
silent in the body of everyone who has had chickenpox. In an estimated
one out of seven people over the course of an 85-year lifetime, the
virus can reappear as a painful rash called shingles.
Many more years of follow-up study in healthy persons are needed
to determine the chickenpox vaccine's effect on shingles development
in later life. In the meantime, studies in leukemic children indicate
that the vaccine may help decrease one's chances for shingles .
A major study is underway to determine whether vaccination can decrease
the incidence an/or severity of shingles and its complications in
adults 60 years of age and older who have had natural chickenpox.
An earlier, small U.S. study, indicated that vaccination may boost
an older person's immunity, potentially decreasing his/her chance
The National Shingles Foundation believes that the use of the chickenpox
vaccine should be considered for all adults and children who have
not had chickenpox. The Foundation strongly urges you to discuss the
vaccine with your doctor. You may also wish to share this booklet
with your doctor.
1. A single dose for children one to 12 years of age and two
doses (four to eight weeks apart) for those 13 years of age and older.
2. The vaccine can be given to some children with underlying
leukemia whose disease is under control.
3. Doctors have found that some children who developed chickenpox
following vaccination were unknowingly exposed to the virus before
vaccination. In these cases, the vaccine was given too late for it
to do its job.
4. In studies involving leukemic children, researchers observed
that those who were given the chickenpox vaccine were nine times less
likely to get shingles than leukemic children who had natural chickenpox.
Leukemic children, who are at a high risk for chickenpox-related death,
began receiving the vaccine several years before it was approved for
use in the general public.