Risks or side effects of the new chicken-pox vaccine?
'The chicken-pox vaccine is usually well tolerated,' says E.
Lawrence Hoder, MD, from the Department of Pediatric and
Adolescent Medicine at Lahey Medical Center in Burlington,
Massachusetts. 'The most common side effects associated with
the vaccine are pain and redness at the injection site.'
Other reported side effects include respiratory tract illness,
chills, fever, irritability, fatigue, sleep disturbance,
gastrointestinal disturbance, rashes, itching, and joint and
muscle aches, although these symptoms have not yet been
positively identified as being vaccine related. Approximately
three to five percent of vaccinated individuals develop a
chickenpox-like rash within 5 to 30 days from vaccination.
Chicken pox is caused by exposure to a highly contagious
airborne varicella-zoster virus (VZV). The illness typically
begins with fever, malaise and a rash. The rash begins as flat
red patches that evolve into patches with a central blister,
the classic “dew drop on a rose petal.” These patches then dry
and scab. New eruptions occur daily for four to seven days.
The average child gets a total of 500 chicken pox sores.
Complications in healthy children are unusual but include
secondary skin bacterial infections, neurologic complications,
hepatitis and Reye’s Syndrome (a serious illness that can
cause recurrent vomiting, liver problems and seizures). For
most children, chicken pox will be a fairly benign illness.
The economic consequences due to lost time at work for
caregivers usually far outweighs any health risk. For adults
and immunocompromised persons, however, infection with chicken
pox may cause severe complications, such as pneumonia that
“Once a person has had chicken pox, he or she will usually
have a lifelong immunity to the disease,” says Dr. Hoder.
“Rarely, however, a person will experience a second, milder
case of chicken pox later in life.” It is important for
parents to understand that having the vaccine may not provide
such protection. The need for revaccination has not yet been
determined. Similar to measles vaccine, a “booster” dose may
Currently, the American Association of Pediatricians
recommends a vaccination for all susceptible children greater
than one year of age. As of August 1998, the State of
Massachusetts requires the vaccine (or a physician-certified
reliable history of chicken pox) for entrance into daycare or
preschool for children who are 19 months or older and who were
born on or after January 1997; by the 1999-2000 school year,
vaccinations will be required for entrance into kindergarten
or for those children already in school, for entrance into 7th
When Not to Vaccinate
The chicken pox vaccine should not be administered to
adults or children who have the following conditions:
A history of hypersensitivity to any component of
the vaccine, including gelatin
A history of an allergic reaction to neomycin
Blood disorders (other than simple anemia) or
A condition or treatment resulting in an
immunosuppressed state, for example, immunoglobulin
deficiency, AIDS, or corticosteroid therapy
A family history of an immunodeficiency
Active, untreated tuberculosis
Any illness that produces a fever
Pregnancy (or a considered pregnancy in the
three-month period following administration of the vaccine)
Individuals who receive the vaccine should avoid taking
aspirin (salicylate) for at least six weeks after the
vaccination. Because vaccinated individuals may be able to
transmit the virus to close contacts, vaccinated persons
should avoid close association with susceptible, high-risk
persons. This risk of transmission is probably small and is
more likely to occur if the vaccinated individual developed a
rash after vaccination.