Chickenpox is spread in the droplets an infected person breathes, sneezes or coughs out, and in the fluid in the blisters on their skin.
It's highly contagious and can easily be caught through close contact with someone who has it, including through:
Chickenpox can also be caught by touching the rash caused by shingles.
Someone with chickenpox is infectious from about one to two days before the rash develops, until all the blisters have fully crusted over.
Read more about chickenpox.