From the Guidelines
Herpes zoster (shingles) is contagious, but only in a limited way, and can be transmitted to people who have never had chickenpox or the chickenpox vaccine, potentially causing chickenpox in these individuals, not shingles. The virus that causes shingles can be spread through direct contact with the fluid from shingles blisters, not through airborne spread 1. A person with shingles remains contagious until all blisters have crusted over, typically within 7-10 days after the rash appears.
Key Points to Consider
- Transmission of the virus occurs via direct contact, airborne droplets, or infected respiratory tract secretions, but in the case of shingles, it is primarily through direct contact with the fluid from shingles blisters 1.
- To prevent transmission, it is recommended to cover the rash, avoid touching or scratching it, wash hands frequently, and avoid contact with high-risk individuals such as pregnant women, newborns, and immunocompromised people.
- Shingles itself develops when the varicella-zoster virus, which remains dormant in nerve tissue after a chickenpox infection, reactivates later in life, typically triggered by factors like aging, stress, or weakened immunity, not by catching it from someone else 1.
Prevention and Precautions
- The risk of herpes zoster after immunization seems to be lower than the risk of zoster after wild-type varicella infection 1.
- Available data indicate that approximately 20% to 30% of people over a lifetime develop herpes zoster, with disease incidence increasing markedly beginning at approximately 50 years of age 1.
From the Research
Contagiousness of Herpes Zoster
- Herpes zoster, also known as shingles, is caused by the reactivation of the varicella-zoster virus, which is the same virus that causes chickenpox 2, 3, 4, 5, 6.
- The virus can be spread from person to person through direct contact with the rash, but only to people who have not had chickenpox or have not been vaccinated against it 4, 5.
- Herpes zoster itself is not contagious, but the varicella-zoster virus can be spread to others, causing chickenpox in those who are not immune 2, 3, 4, 5, 6.
- People with weakened immune systems, such as those with cancer, HIV, or taking immunosuppressive drugs, are more likely to develop herpes zoster and may be more contagious 2, 3, 6.
Transmission and Prevention
- The varicella-zoster virus can be spread through the air when an infected person coughs or sneezes, or through direct contact with the rash 4, 5.
- The virus can also be spread through contact with contaminated objects or surfaces 5.
- Vaccination against varicella-zoster virus can prevent herpes zoster and reduce the risk of transmission to others 2, 4, 6.
- Antiviral medications, such as acyclovir, valacyclovir, and famciclovir, can help treat herpes zoster and reduce the risk of transmission to others 2, 3, 4.