Is shingles (herpes zoster) contagious?

Shingles Contagiousness

Yes, shingles is contagious, but only to people who have never had chickenpox or the varicella vaccine, and these individuals would develop chickenpox, not shingles. 1

Transmission of Varicella-Zoster Virus (VZV)

Shingles (herpes zoster) is caused by the reactivation of the varicella-zoster virus that has remained dormant in sensory nerve ganglia after a primary chickenpox infection. The virus can be transmitted in the following ways:

• Direct contact with the fluid from shingles vesicles 2
• Inhalation of aerosols from vesicular fluid of skin lesions 2
• Contact with infected respiratory tract secretions 2

The virus enters a susceptible person through the upper respiratory tract or conjunctiva 2.

Contagious Period

• A person with shingles is contagious from the appearance of the first vesicles until all lesions have dried and crusted 1
• This typically occurs 7-10 days from the onset of the rash 1
• The period ends when no new lesions appear within a 24-hour period 1

Important Distinctions

• Shingles itself is not transmitted from person to person - only the virus can be transmitted 2
• When a susceptible person is exposed to the virus from someone with shingles, they will develop chickenpox (primary VZV infection), not shingles 1
• Shingles occurs only as a reactivation of the virus in someone who previously had chickenpox or the vaccine 1

Risk of Transmission

The risk of transmission from someone with shingles is lower than from someone with chickenpox, but it still exists, particularly when:

• Lesions are widespread or cannot be covered 1
• The person with shingles has contact with immunocompromised individuals 1
• The person with shingles has contact with pregnant women who have never had chickenpox 1
• The person with shingles has contact with unvaccinated infants 2

Prevention of Transmission

To prevent transmission of VZV from shingles lesions:

• Keep all lesions covered with bandages or clothing 1
• Avoid direct contact with susceptible individuals (especially pregnant women who never had chickenpox, immunocompromised people, and unvaccinated infants) 1
• Wash hands frequently 1
• Avoid scratching the rash 1

Special Considerations

• Healthcare workers with localized zoster should have all lesions completely covered before returning to work 1
• Students with shingles should not return to school until all lesions are dried and crusted 1
• Immunocompromised individuals with shingles may be contagious for longer periods due to prolonged viral replication 2

Vaccination

Vaccination against herpes zoster is recommended for:

• Immunocompetent adults aged 50 years or older 1
• Immunocompromised patients 19 years and older 1

The recombinant zoster vaccine (RZV, Shingrix) is more effective than the older live-attenuated vaccine and is safe even for immunocompromised individuals 3.