The varicella-zoster virus causes
chickenpox. In rare cases, a person infected with the
virus may develop a slightly different form of chickenpox. These variations
include the following.
Varicella bullosa
Varicella bullosa is a type of chickenpox mainly seen in children
younger than 2. The rash is made up of large blisters instead of small
blisters. However, the course of the illness is the same as chickenpox.
Congenital varicella syndrome
When a woman has chickenpox during pregnancy, she passes the virus
to her fetus. The fetus then gets chickenpox. This is called congenital
varicella syndrome.
Complications from chickenpox in a fetus are very rare. However, if
a fetus has chickenpox in the first 3 months of development, he or she may be
born with certain birth defects such as one limb (usually a leg) smaller than
the other, scars on the limbs, or eye problems such as cloudy lenses. The baby
can also weigh less than expected at birth, develop seizures, or have mental
retardation.
Fetuses who get chickenpox from their mothers will not have
chickenpox again. However, they can still have
shingles. They may even have shingles as babies or
young children.