This vaccine helps prevent chickenpox (varicella) caused by the varicella virus, which is transmitted through saliva droplets or direct contact with the lesions or rashes of an infected person.

The infectious period occurs from 2 days before the rash appears until all lesions have dried. Early symptoms include fever, fatigue, itching, followed by the appearance of raised red spots or rashes that usually start on the face and scalp and may spread to other parts of the body.

Chickenpox can lead to severe skin infections, scarring, pneumonia, encephalitis (brain inflammation), and Reye syndrome.