Adult chickenpox transmission occurs via direct contact with someone infected with the chickenpox virus or through the air from an infected person's coughing or sneezing. Less commonly, chickenpox transmission can occur when someone comes into direct contact with a person who has an active herpes zoster (shingles) infection.
A person with chickenpox is contagious 1-2 days before the rash appears and until all blisters have formed scabs.
The usual adult chickenpox incubation period is 14-16 days (ranging between 10-21 days), the same as for children.
In 1995, the Food and Drug Administration approved the varicella vaccine, also known as the chickenpox vaccine, for the prevention of chickenpox.
The chickenpox vaccine is the best way to prevent chickenpox, therefore protecting adults from the severe potential complications (including death) that can occur with chickenpox. If an adult has not had chickenpox and has not already received the chickenpox vaccine, he or she should. People age 13 and older who have not had chickenpox or the chickenpox vaccine should get two doses of the vaccine 4 to 8 weeks apart.
The chickenpox varicella vaccine is especially important for the following groups of susceptible adults:
- People who have close contact with those at high risk for serious complications. For example, healthcare workers and family members/close contacts of people with impaired immune systems.
- People who live or work in environments in which chickenpox transmission is likely. For example, teachers of young children, childcare employees, and residents/staff in institutional settings.
- People who live or work in places where chickenpox transmission can readily occur, including college students, inmates and staff of correctional institutions, and military personnel.
- Non-pregnant women of childbearing age (women should avoid pregnancy for 1 month following each vaccine dose).
- Adolescents and adults living in households with children.
- International travelers.
However, all healthy susceptible adults should be vaccinated.