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"Chickenpox Parties"—Don't Take the Chance

"Chickenpox parties" have been held to intentionally expose a child with chickenpox to other children in hopes that they will get the disease. Chickenpox can be serious, especially for infants and even for some children. So, it is not worth taking the chance of exposing them to chickenpox. The best way to protect infants and children against chickenpox is to get them vaccinated. Read more about the chickenpox vaccine.

Pregnant women and people with weakened immune systems, who are not protected against chickenpox and cannot be vaccinated, are more likely to get a serious case of chickenpox. They should stay away from people with chickenpox and should not go to chickenpox parties.

Chickenpox is a very contagious disease caused by the varicella-zoster virus. The virus spreads easily from people with chickenpox to others who have never had the disease or been vaccinated. The virus spreads mainly by touching or breathing in the virus particles that come from chickenpox blisters, and possibly through tiny droplets from infected people that get into the air after they breathe or talk, for example.  

The Varicella-zoster virus also causes shingles. Chickenpox can be spread from people with shingles to others who have never had chickenpox or received the chickenpox vaccine. This can happen if a person touches or breathes in virus from shingles blisters. In these cases, a person might develop chickenpox, not shingles. For more information about shingles, see Transmission.

When Is a Person Contagious?

A person with chickenpox can spread the disease from 1 to 2 days before they get the rash until all their chickenpox blisters have formed scabs (usually 5-7 days).

It takes about 2 weeks (from 10 to 21 days) after exposure to a person with chickenpox or shingles for someone to develop chickenpox.

If a person vaccinated for chickenpox gets the disease, they can still spread it to others.

For most people, getting chickenpox once provides immunity for life. However, for a few people, they can get chickenpox more than once, although this is not common.

For information about how to prevent chickenpox, see Prevention & Treatment.