Shingles is contagious from the time the rash appears and the blisters are in the active, fluid-filled phase until the blisters have crusted and scabbed over. This contagious period typically lasts about 7 to 10 days, but it depends more on the status of the rash than the exact number of days. Once all blisters have dried and formed crusts, which can take 2 to 4 weeks, the person is no longer contagious
. The varicella-zoster virus that causes shingles can be spread through direct contact with the fluid from the active blisters. People who have never had chickenpox or the chickenpox vaccine can catch chickenpox (not shingles) from this exposure. The virus can also be spread through airborne particles from the blisters, although this is less common
. In summary:
- Contagious period: from blister formation until all blisters have crusted over (about 7-10 days).
- After crusting, the risk of transmission is greatly reduced or eliminated.
- Transmission occurs through direct contact with blister fluid or, less commonly, airborne particles from the rash.
- Only people who have never had chickenpox or the vaccine are at risk of catching chickenpox from someone with shingles.
This means precautions such as keeping the rash covered and avoiding direct contact with others until the blisters have crusted are important to prevent spreading the virus
