Exams and Tests
Chickenpox (varicella) usually can be diagnosed by the
appearance of the
chickenpox rash
. For healthy children, describing the
rash over the phone to a health professional (rather than visiting the office)
may be all that is needed.
But some people need to see a health
professional when symptoms of chickenpox appear. You are at more risk for
complications from chickenpox if you are a teenager, adult (especially if you
smoke cigarettes or have a long-term lung disease), or a pregnant woman, or you
have an
impaired immune system.
If you visit
your health professional's office, chickenpox is diagnosed by
medical history and
physical exam.
Viral tests
can determine whether you are
immune to the virus and are unlikely to get
chickenpox.
If you have a blistering rash and it's not known if
it was caused by the chickenpox virus, other tests can be done.
A
woman who has chickenpox early in her pregnancy may want to have her
fetus checked for birth defects. This can be done with
a
fetal ultrasound.
Early Detection
There is no general screening for immunity against chickenpox at
this time. Most people in the United States had chickenpox as children and have
immunity against it.
Some people may be required to be tested for chickenpox
immunity. These include people who work in hospitals, day care centers,
schools, and other areas where chickenpox can easily be passed from one person
to another. Many states now require that children entering day care and school
have the
chickenpox vaccine
(What is a PDF document?) unless they have a doctor's diagnosis or blood test results
that prove immunity.
If you are more likely to get severely ill
from chickenpox or to have
complications of chickenpox, you also need to be
tested to confirm whether you have ever had chickenpox and have immunity
against it. These people include:
- People with impaired immune systems.
- Women who are
able to have children. Women who are pregnant or who want to become pregnant
should consider being tested to see whether they have chickenpox immunity.
Having chickenpox immunity prevents
complications of chickenpox during pregnancy.
If you have never had chickenpox and therefore do not
have immunity against it, you may choose to get the chickenpox vaccine
(Varivax). Talk with your health professional about the risks and benefits of
the chickenpox vaccine.