HERPES ZOSTERWHY THE CAT CAME BACK

ARE ZOSTER RATES INCREASING? IMMUNIZATION?

• In the U.S. population older than 65 years, age-specific HZ incidence increased 39% from 10.0 per 1000 person-years in 1992 to 13.9 per 1000 person-years in 2010 with no evidence of a statistically significant change in the rate of increase after introduction of the varicella vaccination program. • Introduction and widespread use of the vaccine did not seem to affect this

increase.

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EPIDEMIOLOGY• The incidence of HZ remains stable as the incidence of varicella is decreasing:• In one US HMO: Age-adjusted and -specific annual incidence rates of HZ fluctuated slightly over

time; the age-adjusted rate was highest, at 4.05 cases/1000 person-years, in 1992, and was 3.71 cases/1000 person-years in 2002.• The age-adjusted rates decreased from 2.63 cases/1000 person-years during 1995 to 0.92

cases/1000 person-years during 2002; there was a 75% decrease in children 1-4 years old between 1992-1996 and 2002.

• Vaccinated children are less likely to become infected with wild-type chickenpox virus, which is more likely to reactivate as shingles compared to attenuated vaccine virus.• Reassuring for countries considering universal varicella vaccination.

I HAVE ZOSTER AT 41 – AM I IMMUNOCOMPROMISED?• Almost 1 out of 3 people in the United States will develop shingles during

their lifetime. • The presence of a few skin lesions outside the primary or adjacent

dermatomes is neither unusual nor of prognostic importance in immunocompetent patients.

• Simultaneous involvement of multiple non-contiguous dermatomes is very rare in immunocompetent patients, but overlapping in adjacent dermatomes occurs in 20%.

• About 1 - 4% of people with shingles are hospitalized for complications. Older adults and people with weakened or suppressed immune systems are more likely to be hospitalized. About 30% of people hospitalized for shingles have a weakened or suppressed immune system.

*per 1,000 person-years.

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ZOSTER AND IMMUNOSUPPRESSION• Incidence of zoster is higher in those receiving immunosuppressive therapy

for autoimmune conditions: Biologics (TNF blockers), DMARDs, and Corticosteroids (2)• Relative risk (RR) of 3.0 (95% CI: 1.1, 7.8) for herpes zoster during WGET

treatment with etanercept (P=.03)

SHOULD WE THINK OF CANCER?• 590 residents of Rochester, Minnesota, for 9389 person-years after the diagnosis of

herpes zoster. (3) (N Engl J Med. 1982; 307:393–7.)• The overall relative risk was 1.1 (95 per cent confidence interval, 0.9 to 1.3). • Slightly elevated relative risks for specific cancer sites only for colon and bladder

tumors in women• Patients with disseminated, recurrent, or gangrenous zoster, with post-herpetic

neuralgia, or with ophthalmic zoster were not at elevated risk for subsequent cancer• Screening for cancers in zoster is not recommended

SHOULD I RECEIVE ANTIVIRALS?• Therapy for herpes zoster should accelerate healing, limit the severity and duration of acute and chronic pain,

and reduce complications. Treatment should be targeted for:• Immunocompromised patients, to reduce the risk of dissemination of VZV• Persons at highest risk for complications are elderly persons, those with herpes zoster ophthalmicus, and

immunocompromised patients. • Older age, a greater degree of skin-surface area involved, and more severe pain at presentation are all

predictors of persistent pain (post-herpetic neuralgia). • All patients with acute herpes zoster ophthalmicus should receive antiviral therapy with the goal of preventing

ocular complications. • Some physicians still consider antiviral therapy to be optional for younger patients with uncomplicated shingles,

although therapy has minimal risk and is potentially beneficial.

VACCINATE

REFERENCES1. http://www.medscape.com/viewarticle/822982 CDC Expert Series on Zoster – MedSCape2. http://ofid.oxfordjournals.org/content/2/suppl_1/1203.extract# Open Oxford journals3. http://www.nejm.org/doi/10.1056/NEJM198208123070701 Cancer risk in Zoster4. http://www.cdc.gov/vaccines/pubs/pinkbook/varicella.html CDC Pink Book5. http://www.cdc.gov/shingles/hcp/clinical-overview.html CDC Zoster for Healthcare Professionals6. http://www.who.int/immunization/sage/meetings/2014/april/2_Background_document_Herpes_Zoster.pdf WHO Background document on Zoster7. http://www.jwatch.org/jw200711150000001/2007/11/15/what-incidence-shingles NEJM Incidence of Shingles8. http://www.medscape.com/medline/abstract/23036671 MedLine Abstract Risks for Shingles9. http://www.medscape.com/medline/abstract/15897984 Incidence of herpes zoster, before and after varicella-vaccination-associated decreases

in the incidence of varicella, 1992-2002. J Infect Dis. 2005; 191(12):2002-7 (ISSN: 0022-1899)10. http://www.medscape.com/medline/abstract/24297190 Examination of links between herpes zoster incidence and childhood varicella

vaccination. Ann Intern Med. 2013; 159(11):739-45 (ISSN: 1539-3704)11. https://www.ncbi.nlm.nih.gov/pubmed/16378799 Zoster in immunocompromised patients