Correspondence
An Outbreak of Varicella despite Vaccination
N Engl J Med 2003; 348:1405-1407April 3, 2003
- Article
To the Editor:
In her editorial on the article by Galil et al. (Dec. 12 issue),1 Gershon2 states that the time to explore the routine administration of a second dose of the varicella vaccine has arrived. I agree, but Gershon fails to mention the issue that will truly tip the balance in favor of recommending the second dose of this vaccine. The possibility of secondary vaccine failure due to the waning of immunity will soon be a valid concern in young women of childbearing age who received one dose before the age of 12 years. Young adults who were vaccinated in 1995, after approval of the vaccine by the Food and Drug Administration, are now approaching their childbearing years.
Fetal infection after maternal varicella infection during the first or second trimester of pregnancy occasionally results in varicella embryopathy, which is characterized by limb atrophy and scarring of the skin of the arms or legs (i.e., the congenital varicella syndrome).3 Central nervous system and eye manifestations can also occur. The report of a varicella outbreak at a day-care center1 demonstrates that mild cases of varicella (“breakthrough varicella”) are possible in recently vaccinated children. Are mild cases of varicella in vaccinated children less likely than cases in unvaccinated children to cause the congenital varicella syndrome?
3 ReferencesRobert J. Giusti, M.D.
Long Island College Hospital, Brooklyn, NY 112011
Galil K ,Lee B ,Strine T , et al. Outbreak of varicella at a day-care center despite vaccination. N Engl J Med 2002;347:1909-1915
Full Text | Web of Science | Medline2
Gershon AA . Varicella vaccine -- are two doses better than one? N Engl J Med 2002;347:1962-1963
Full Text | Web of Science | Medline3
Pickering LK, ed. 2000 Red book: report of the Committee on Infectious Diseases. 25th ed. Elk Grove Village, Ill.: American Academy of Pediatrics, 2000:625.
To the Editor:
Gershon states in her editorial that “the time for exploring the possibility of routinely administering two doses of varicella vaccine to children seems to have arrived.” The report by Galil et al. raises a more important issue: reversal of the decision to mandate universal varicella vaccination. The logic behind the initial varicella immunization recommendation1 was based largely on the assumption of substantial economic benefits from “social cost” savings. All the analyses cited to substantiate this claim assumed only one vaccination, and none found any economic benefit from direct medical cost savings.2,3 As Gershon acknowledges, more than one dose is almost certainly required to ensure a reasonable level of immunity. Therefore, the economic arguments for universal immunization must also be revisited and probably discarded. Gershon's conjecture about shingles appears to be the only remaining reason for an immunization program costing approximately $150 million per year. Let us acknowledge the shaky assumptions underpinning the original decision on immunization and consider a more justifiable policy of voluntary immunization for children and mandatory immunization for nonimmune teenagers and adults.
3 ReferencesRobert P. Wack, M.D.
Carroll County General Hospital, Westminster, MD 21157
rwack@ccgh.com 1
American Academy of Pediatrics Committee on Infectious Diseases
Web of Science | Medline2
Preblud SR ,Orenstein WA ,Koplan JP ,Bart KJ ,Hinman AR . A benefit-cost analysis of a childhood varicella vaccination programme. Postgrad Med J 1985;61:Suppl 4:17-22
Web of Science | Medline3
Lieu TA ,Cochi SL ,Black SB , et al. Cost-effectiveness of a routine varicella vaccination program for US children. JAMA 1994;271:375-381
CrossRef | Web of Science | Medline
To the Editor:
Gershon states that the United States is the only country using universal mass vaccination against chickenpox. However, in 1999, the varicella vaccine was introduced into the routine vaccination schedule in Uruguay, where it is coadministered with the combined measles–mumps–rubella vaccine at the age of 12 months, as in the United States. The vaccine used, Varilrix, is similar to the U.S.-licensed vaccine Varivax, in that it is also derived from the Oka strain; however, it is less labile than Varivax and does not need to be stored in the freezer.
Vaccines that are part of the recommended schedule are offered free of charge in Uruguay, and varicella vaccination coverage has been estimated at 93 percent nationwide since 1999.1 Provisional data indicate a decline from 74 to 29 admissions for varicella per 10,000 admissions between 1998 and 2001 at Hospital Pereira Rossell, the chief pediatric reference hospital in Montevideo.
1 ReferencesJorge W. Quian, M.D.
Hospital Pereira Rossell, 11600 Montevideo, Uruguay
jquian@asesp.com. uy Author/Editor Response
Since the varicella vaccine was recommended for routine use in children in the United States, varicella disease and hospitalizations for it have declined substantially.1 Postlicensure data confirm that the varicella vaccine is both safe and effective, especially in preventing severe disease.2 In the outbreak we describe in our article, the effectiveness of this vaccine in preventing all disease was the lowest observed to date, but the vaccine was 86 percent effective in preventing moderate or severe varicella. This finding provides reassurance that vaccinated children and adults are protected from the severe consequences of varicella disease. Furthermore, the results of this investigation and attendant policy deliberations should be understood in the context of the many investigations and studies that have shown effectiveness in the expected range2 and a decline in disease.1
Before the varicella-vaccination program was introduced in the United States, varicella was responsible for more than 100 deaths and more than 10,000 hospitalizations every year. Despite the common belief that in children varicella is a benign disease, the greatest burden of disease occurred among children, who accounted for more than 90 percent of the cases, two thirds of the hospitalizations, and almost half the deaths.3,4
Vaccinations are one of the most cost-effective public health measures available. Because of the high burden of disease from varicella among children, vaccinating only teenagers and adults will have little effect on the epidemiologic features of varicella. The Vaccines for Children Program in the United States has eliminated cost barriers for routinely recommended childhood vaccines, including the varicella vaccine, for which there are no disparities in vaccine coverage according to race, ethnic background, or income level.5 A program of voluntary vaccination for children, as suggested by Wack, would result in availability of the vaccine only to those who could pay for it or whose health insurance covered it — a situation that would result in inequities in access to beneficial preventive health measures. In addition, the moderate levels of vaccination coverage that would result from a voluntary childhood vaccination program would increase morbidity and mortality among older children and adults unless all susceptible adolescents and adults were successfully vaccinated. High vaccination coverage among adults has not been successfully achieved for several vaccines with proven benefit.
Varicella disease and its serious consequences are now declining in the United States. The Centers for Disease Control and Prevention will continue to monitor all aspects of the varicella-vaccination program and use the data to assist in future policy decisions.
5 ReferencesJane Seward, M.B., B.S., M.P.H.
Centers for Disease Control and Prevention, Atlanta, GA 30033
jseward@cdc.gov Karin Galil, M.D., M.P.H.
Cubist Pharmaceuticals, Lexington, MA 02421Aisha Jumaan, Ph.D., M.P.H.
Centers for Disease Control and Prevention, Atlanta, GA 300331
Seward JF ,Watson BM ,Peterson CL , et al. Varicella disease after introduction of varicella vaccine in the United States, 1995-2000. JAMA 2002;287:606-611
CrossRef | Web of Science | Medline2
Seward JF . Update on varicella. Pediatr Infect Dis J 2001;20:619-621
CrossRef | Web of Science | Medline3
Meyer PA ,Seward JF ,Jumaan AO ,Wharton M . Varicella mortality: trends before vaccine licensure in the United States, 1970-1994. J Infect Dis 2000;182:383-390
CrossRef | Web of Science | Medline4
Galil K ,Brown C ,Lin F ,Seward J . Hospitalizations for varicella in the United States, 1988-1999. Pediatr Infect Dis J 2002;21:931-935
CrossRef | Web of Science | Medline5
Immunization coverage in the U.S. Atlanta: CDC National Immunization Program, 2002. (Accessed March 14, 2003, at http://www.cdc.gov/nip/coverage.)
Author/Editor Response
The live attenuated varicella vaccine is extremely safe and has proved to be highly effective in preventing chickenpox in clinical practice.1-3 The outbreak described by Galil et al. is not representative of the general experience regarding the effectiveness of the vaccine, but it does present a possible warning. It remains unclear whether immunity to varicella wanes substantially after vaccination and whether any particular group, such as persons with asthma, might be more susceptible than others to such a phenomenon. Study of these issues is under way. Primary failure is, however, also a real consideration for this labile vaccine and may account for the reported outbreak at a day-care center.
A second dose of the varicella vaccine, given routinely, could ameliorate both of these possible problems and must, in my opinion, now be explored. To discontinue routine vaccination in the United States now would be a disservice to our population and would bring back substantial rates of hospitalization and death due to varicella and possibly zoster in both children and adults. Economic issues are important, but they are not the only consideration with regard to vaccines. As noted by Galil et al., it is not wise to make policy statements on the basis of one outbreak.
3 ReferencesAnne A. Gershon, M.D.
Columbia University College of Physicians and Surgeons, New York, NY 10032
aag1@columbia.edu 1
Vazquez M ,LaRussa PS ,Gershon AA ,Steinberg SP ,Freudigman K ,Shapiro ED . The effectiveness of the varicella vaccine in clinical practice. N Engl J Med 2001;344:955-960
Full Text | Web of Science | Medline2
Seward JF ,Watson BM ,Peterson CL , et al. Varicella disease after introduction of varicella vaccine in the United States, 1995-2000. JAMA 2002;287:606-611
CrossRef | Web of Science | Medline3
Sharrar RG ,LaRussa P ,Galea SA , et al. The postmarketing safety profile of varicella vaccine. Vaccine 2000;19:916-923
CrossRef | Web of Science | Medline
- Citing Articles (1)
Citing Articles
1
M. Carolina Danovaro‐Holliday, Ely R. Gordon, Aisha O. Jumaan, Charles Woernle, Randa H. Judy, D. Scott Schmid, Jane F. Seward. (2004) High Rate of Varicella Complications among Mexican‐Born Adults in Alabama. Clinical Infectious Diseases 39:11, 1633-1639
CrossRef
