Zoster Vaccine After Shingles? When-and Why

In the February 2010 issue of CONSULTANT, we published a question from John Mosby, MD, who wanted to know why the zoster vaccine had been administered to an older man in an earlier Photoclinic case (Ophthalmic Zoster) who had ophthalmic zoster. We also published the response from Dr Tran, which cited the Advisory Committee on Immunization Practices (ACIP) recommendation to administer the vaccine to all patients 60 years or older in whom it is not contraindicated, including those with a history of previous zoster.

A number of readers wrote us regarding this exchange. Some voiced their frustration that the rationale for the ACIP recommendation had not been provided. Others expressed reservations about the recommendation. Still others provided insights into the rationale behind the recommendation and suggestions regarding its application in actual practice. A sampling of these letters follows.

Dr Tran's reply in the Consultations & Comments exchange, "Why Is Zoster Vaccine Needed After Shingles?" did not answer the question Dr Mosby asked-namely, why the zoster vaccine is needed after shingles. Dr Tran merely stated that the vaccine can be given to patients who have had shingles. However, the question is not "is the vaccine safe or not contraindicated?" but "why is it necessary?"

What I-and probably Dr Mosby and many other practitioners-want to know is whether there is a clinical benefit to giving the vaccine after an outbreak of shingles. In the context of population immunization protocols, Dr Tran's answer is relevant. However, Dr Mosby's question applies to a specific clinical situation, one that we all see frequently-and that deserves a specific answer.

Robert P. Blereau, MD, of Morgan City, La, sent us this quote from Morbidity and Mortality Weekly Report,¹ which explains why the ACIP recommends the zoster vaccine even in persons with a reported history of zoster:

Repeated zoster has been confirmed in immunocompetent persons soon after a previous episode.

⁴

Although the precise risk for and severity of zoster as a function of time following an earlier episode are unknown, some studies suggest it may be comparable to the risk in persons without a history of zoster.

^62,169

Furthermore, no laboratory evaluations exist to test for the previous occurrence of zoster, and any reported diagnosis or history might be erroneous.

^4,64,65

Although the safety and efficacy of zoster vaccine have not been assessed in persons with a history of zoster, different safety concerns are not expected in this group.

REFERENCES:

4.

Oxman MN, Levin MJ, Johnson GR, et al. A vaccine to prevent herpes zoster and postherpetic neuralgia in older adults.

N Engl J Med

. 2005;352:2271-2284.

62.

Yawn BP, Saddier S. Wollan P, et al. A population-based study of the incidence and complications of herpes zoster before zoster vaccine introduction.

Mayo Clin Proc

. 2007;82:1341-1349.

64.

Rubben A, Baron JM, Grussendorf-Conen EI. Routine detection of herpes simplex virus and varicella zoster virus by polymerase chain reaction reveals that initial herpes zoster is frequently misdiagnosed as herpes simplex.

Br J Dermatol

. 1997;137:259-261.

65.

Kalman CM, Laskin OL. Herpes zoster and zosteriform herpes simplex virus infections in immunocompetent adults.

Am J Med

. 1986;81:775-778.

169.

Molin A. Aspects of the natural history of herpes zoster: a follow-up investigation of outpatient material.

Acta Derm-Venereol

. 1969;49:569-583.

REFERENCE:1. Harpaz R, Ortega-Sanchez IR, Seward JF; Advisory Committee on Immunization Practices (ACIP) Centers for Disease Control and Prevention (CDC). Prevention of herpes zoster: recommendations of the Advisory Committee on Immunization Practices (ACIP) [published correction appears in MMWR Recomm Rep. 2008;57:779]. MMWR Recomm Rep. 2008;57(RR-5):1-30.

The Consultations & Comments exchange between Drs John Mosby and Khiem Tran in the February issue of CONSULTANT discusses the question "why is the zoster vaccine needed after shingles?" Unfortunately, Dr Tran does not discuss the rationale for this recommendation.

The Shingles Prevention Study excluded patients with a history of zoster¹; thus, there are no published data on the safety or efficacy of the vaccine in this population. The ACIP nevertheless recommends use of the vaccine without respect to prior zoster because zoster can recur; in addition, the vaccine might have some benefit in preventing recurrence.² However, Dr Mosby is correct to question that benefit, since there are no published data to support the theoretical value of the vaccine in this setting. This fact, as well as the absence of any way to identify which patients with a history of zoster might benefit from the vaccine, was recognized by the ACIP.

The vaccine is not inexpensive, and because for many patients it is covered by their Medicare Part D plan, the cost to the patient can be substantial. I feel that it is appropriate to discuss the absence of proven benefit, the cost, and the ACIP recommendation with patients who ask about the use of the vaccine after they have had shingles.

REFERENCES:1. Oxman MN, Levin MJ, Johnson GR, et al; Shingles Prevention Study Group. A vaccine to prevent herpes zoster and postherpetic neuralgia in older adults. N Engl J Med. 2005;352:2271-2284.
2. Harpaz R, Ortega-Sanchez IR, Seward JF; Advisory Committee on Immunization Practices (ACIP) Centers for Disease Control and Prevention (CDC). Prevention of herpes zoster: recommendations of the Advisory Committee on Immunization Practices (ACIP) [published correction appears in MMWR Recomm Rep. 2008;57:779]. MMWR Recomm Rep. 2008;57(RR-5):1-30.

Dr Mosby's question was specific and reasonable. However, Dr Tran's answer dealt mainly in generalities, leaving the reader unsatisfied. Several years ago, I had concerns similar to Dr Mosby's and sought clarification from the ACIP. The following response may prove helpful:

Patients often report prior, self-diagnosed episodes of shingle, but the likelihood of misdiagnosis in these cases is high. Because there is no way to confirm a history of shingles, exclusion of patients with reports of prior episodes of shingles would pose a large burden on physicians for assessing the nature of the prior diagnosis and judging its reliability. This would introduce a large barrier to vaccination. Since there are no recognized safety concerns in giving the vaccine to persons with prior shingles, the vaccine should be made available to persons regardless of prior shingles history.

However, it is still not clear why the ACIP chose a "one size fits all" approach for this immunization rather than the approach they have taken with other vaccines, which involves the promulgation of many caveats regarding use in a variety of specific clinical situations.

My approach is to immunize patients who are at risk, providing they do not have a history of a highly probable case of zoster-and providing they can afford the vaccine. I have not seen the specific data, but it is my impression that the rate of zoster recurrence is about the same as the rate of zoster vaccine failure-or less. The information available to the physician can be used to assess the likelihood of accurate diagnosis in prior zoster episodes. Considering the cost of the vaccine and the cost of testing for an antibody titer, the patient's history and a review of the chart should be our guides.

I turned with interest to the Consultations & Comments exchange, "Why Is Zoster Vaccine Needed After Shingles?" in the February issue of CONSULTANT. However, Dr Tran's answer was more a simple reiteration of the current CDC recommendation than a detailed rationale for that recommendation.

There are at least 3 reasons not to give the vaccine to a person with a clearly documented history of shingles.

The only possible justification I can ascertain for giving the vaccine to a person with a history of shingles is that occasionally a patient states that he has had shingles but the physician has no documentation of this. (Patients incorrectly diagnose their presumptive illnesses all the time.) Given the significant expense of the vaccine, I have difficulty in justifying its use in patients for whom there is no documented proof of benefit.

I read with interest the comments from readers about the zoster vaccine, and I thank all who took the trouble to write for their time and effort. The vaccine does have its share of issues and controversies. Thus, to provide optimal individualized management, practicing clinicians need to consider the cost and benefit of the vaccine and the specific needs of each patient, as well as the current recommendations for use of the vaccine.