Herpes zoster is a painful rash that occurs along one or more dermatomes. Zoster is caused by reactivation of latent varicella zoster virus infection from a prior chickenpox infection. People who have had a prior infection with varicella zoster virus (chickenpox) are at risk of shingles.
Ask the Experts: Zoster (Shingles)
During their lifetime about 30% of Americans will develop herpes zoster, which translates into an estimated 1 million cases each year in this country. The risk of zoster increases with increasing age; about half of all cases occur among people age 60 years or older. People who are immunosuppressed, including those with leukemia, lymphoma, and human immunodeficiency virus (HIV) infection, and people who receive immunosuppressive drugs, such as steroids and cancer chemotherapy, also are at greater risk of zoster. Most people have only one episode of shingles. The risk of recurrence is low in people who are not immunosuppressed, but the precise incidence is unknown.
Zoster is caused by reactivation of a latent varicella virus infection (from having chickenpox in the past). Zoster is not passed from one person to another through exposure to another person with zoster. However, if a person who is susceptible to chickenpox (i.e., they had never had chickenpox and were not vaccinated against chickenpox) comes in direct contact with a person with a zoster rash, the virus could be transmitted to the susceptible person. The exposed person would develop chickenpox, not zoster. Covering the zoster rash reduces the chances of transmitting varicella zoster virus.
In a school setting, an immunocompetent person with zoster (staff or students) can remain at school as long as the lesions can be completely covered. People with zoster should be careful about personal hygiene, wash their hands after touching their lesions, and avoid close contact with others. If the lesions cannot be completely covered and close contact avoided, the person should be excluded from the school setting until the zoster lesions have crusted over. See www.cdc.gov/chickenpox/outbreaks/manual.html for more information. If your program is licensed by a state or county, you should check their regulations as well.
All healthcare personnel should ensure they are immune to varicella regardless of the setting in which they work. For healthcare personnel, accepted evidence of varicella immunity includes any of the following: 1) documentation of age-appropriate vaccination with a varicella vaccine, 2) laboratory evidence of immunity or laboratory confirmation of disease; 3) diagnosis or verification of a history of varicella disease by a healthcare provider; or 4) diagnosis or verification of a history of herpes zoster by a healthcare provider.
Recombinant zoster vaccine (RZV, Shingrix, GlaxoSmithKline) was licensed by the Food and Drug Administration (FDA) in October 2017. It is a subunit vaccine that contains recombinant varicella zoster virus (VZV) glycoprotein E in combination with a novel adjuvant (AS01B). Shingrix does not contain live VZV. It is FDA-approved and recommended by the Advisory Committee on Immunization Practices (ACIP) for all people 50 years and older and for adults age 19 years or older who are or will be immunodeficient or immunosuppressed because of disease or therapy. It has not been evaluated and is not approved for the prevention of primary varicella infection. Shingrix is administered as a 2-dose series by the intramuscular route. The second dose should be given 2 to 6 months after the first dose, with a minimum interval of 1 month (4 weeks) between doses.
Zoster vaccine live (ZVL, Zostavax, Merck) is a live attenuated vaccine that was licensed by the FDA in 2006 for adults age 50 and older and recommended by ACIP for people age 60 and older. Zostavax has been unavailable for use in the United States since November 18, 2020.
Shingrix was studied in immunocompetent adults in 2 pre-licensure clinical trials. Efficacy against shingles was 97% for people 50–59 years of age, 97% for people 60–69 years of age, and 91% for people 70 years and older. Among people 70 years and older vaccine efficacy was 85% four years after vaccination.
Vaccine effectiveness (VE) has been evaluated for a limited number of specific immunocompromising conditions. VE estimates vary depending upon the underlying cause of immunocompromise. Studies have estimated VE of 68.2% for autologous hematopoietic cell transplant recipients, and 87.2% and 90.5% for patients with hematologic malignancies and potential immune-mediated diseases, respectively.
Yes. In clinical trials among immunocompetent adults age 50 years or older, Shingrix reduced the risk of PHN by 91%. One study among hematopoietic cell transplant recipients reported that vaccination reduced the risk of PHN by 89%.
Shingrix is recommended for the prevention of herpes zoster and related complications for immunocompetent adults 50 years of age and older, including those who previously received Zostavax. On October 20, 2021, ACIP recommended 2 doses of RZV for the prevention of herpes zoster and related complications in adults age 19 years or older who are or will be immunodeficient or immunosuppressed because of disease or therapy.
ACIP published its zoster vaccination recommendations for immunocompetent adults age 50 years and older in January 2018: www.cdc.gov/mmwr/volumes/67/wr/pdfs/mm6703a5-H.pdf.
ACIP published its recommendations for the use of recombinant zoster vaccine in adults age 19 years or older who are or will be immunocompromised in January 2022: www.cdc.gov/mmwr/volumes/71/wr/pdfs/mm7103a2-H.pdf.
Clinicians and patients should make every effort to ensure that two doses of Shingrix are administered within the recommended interval of 2 to 6 months. If more than 6 months have elapsed since the first dose of Shingrix, administer the second dose when possible. Do not restart the vaccine series.
Additional information for clinicians about Shingrix is available on the CDC website at www.cdc.gov/vaccines/vpd/shingles/hcp/index.html.
Yes. ACIP recommends that people who previously received Zostavax receive 2 doses of Shingrix. The first dose of Shingrix may be given a minimum of 8 weeks after Zostavax.
The recommended interval between Shingrix doses is 2 to 6 months. The minimum interval between doses of Shingrix is 4 weeks. If the second RZV dose is given more than 4 days sooner than 4 weeks after the first dose, a valid second dose should be repeated at least 4 weeks after the dose given too early.
For adults who are or will be immunodeficient or immunosuppressed and who would benefit from a shorter vaccination schedule, the second dose can be administered 1–2 months (a minimum of 4 weeks) after the first dose.
The routinely recommended minimum age for Shingrix among immunocompetent adults is 50 years. However, if a dose is inadvertently administered to an immunocompetent adult 18 through 49 years of age CDC does not recommend repeating the dose. The second Shingrix dose should not be administered until the 50th birthday. This guidance does not appear in the most recent zoster ACIP statement but is in the General Best Practices Guidance (Table 3-1 in the Timing and Spacing of Immunobiologics section at www.cdc.gov/vaccines/hcp/acip-recs/general-recs/timing.html) and is based on guidance from CDC’s zoster subject matter experts.
Among people who are or will be immunosuppressed or immunodeficient due to disease or therapy, the minimum age for vaccination is 19 years.
No. The vaccine series need not be restarted if more than 6 months have elapsed since the first dose.
The action taken depends on why varicella vaccine was given in the first place. If it was given because the person tested negative for varicella antibody, then the next dose should be varicella vaccine. If the varicella vaccine was given in error (i.e., without serologic testing), then Shingrix should be given.
Shingrix may be administered to people who have previously received 2 doses of varicella vaccine. Compared to people who have had chickenpox, the risk of zoster among recipients of varicella vaccine (which contains a live-attenuated strain of varicella virus) is much lower, but is still possible.
All immunocompetent people age 50 years or older-whether they have a history of chickenpox or shingles or not-should be given Shingrix unless they have a medical contraindication to vaccination. Among this population it is not necessary to ask about a history of chickenpox or to test for varicella antibody prior to or after giving the vaccine.
Among immunocompromised people age 19 years or older, evidence of a history of varicella illness or varicella vaccination (confirming the need for Shingrix as a result of a history of exposure to a live varicella virus, whether the wild or live-attenuated vaccine strain) IS recommended. Shingrix may be administered to an immunocompromised person who has had chickenpox or shingles or has previously been vaccinated with varicella vaccine or zoster vaccine live. See the Immunocompromised Adults section for additional information about partially-vaccinated immunocompromised adults with no history of chickenpox.
A person who has never been exposed to varicella virus through infection or vaccination with varicella vaccine or zoster vaccine live is not at risk for shingles. Shingrix has not been evaluated for the prevention of primary infection with varicella virus. People who have never had chickenpox are recommended to receive 2 doses of varicella vaccine.
Serologic studies indicate that about 99% of people born before 1980 worldwide have had chickenpox even though many cannot recall having had chickenpox (www.cdc.gov/mmwr/preview/mmwrhtml/rr5705a1.htm). As a result, there is no need to ask immunocompetent people age 50 years and older for their varicella disease history or to perform a laboratory test for serologic evidence of prior varicella disease.
Immunocompromised adults age 19 years and older without evidence of exposure to live varicella virus through a history of chickenpox, zoster, or documentation of vaccination with live varicella vaccine (Varivax or ProQuad, Merck) or zoster vaccine live (Zostavax, Merck) should be evaluated further. Birth before 1980 is not sufficient proof of immunity for immunocompromised adults. For immunocompromised adults, evidence of immunity to varicella (confirming need for RZV) includes:
- Documentation of two doses of varicella vaccine, or
- Laboratory evidence of immunity or laboratory confirmation of disease, or
- Diagnosis or verification of a history of varicella or herpes zoster by a healthcare provider.
For any adult who is clinically determined to be susceptible to primary varicella infection, refer to the ACIP varicella vaccine recommendations for further guidance, including post-exposure prophylaxis guidance for immunocompromised adults: www.cdc.gov/mmwr/preview/mmwrhtml/rr5604a1.htm.
CDC has published clinical considerations for shingles vaccination of immunocompromised patients who lack evidence of immunity to chickenpox: www.cdc.gov/shingles/vaccination/immunocompromised-adults.html#special-populations.
Yes. Adults with a history of herpes zoster should receive Shingrix. If a person is experiencing an episode of zoster, vaccination should be delayed until the acute phase of the illness is over and symptoms abate.