Journal Article

Alternative Immunological Markers to Document Successful Multiple Smallpox Revaccinations

Itay Wiser, Nadav Orr, Zehava Smetana, Ania Spungin-Bialik, Ella Mendelson and Daniel Cohen

in Clinical Infectious Diseases

Published on behalf of Infectious Diseases Society of America

Volume 52, issue 7, pages 856-861
Published in print April 2011 | ISSN: 1058-4838
Published online April 2011 | e-ISSN: 1537-6591 | DOI:
Alternative Immunological Markers to Document Successful Multiple Smallpox Revaccinations

More Like This

Show all results sharing these subjects:

  • Infectious Diseases
  • Immunology
  • Public Health and Epidemiology
  • Microbiology


Show Summary Details


Background. Successful smallpox vaccination is traditionally defined by clinical response (“take”). Nevertheless, only 60% of subjects in the 2002 Israeli smallpox revaccination campaign developed clinical take. More sensitive immunological markers are needed to document successful revaccination. We compared the level of vaccinia-specific immune markers among subjects who did or did not develop clinical take following revaccination.

Methods. Forty subjects who participated in 2002 smallpox revaccination campaign and developed clinical take were individually matched for age, sex, and smallpox vaccinations with subjects who did not develop clinical take (“no-take”). Vaccinia immunity markers were examined prior to and 14 days and 2 years after revaccination.

Results. Higher levels of total immunoglobulin (Ig) G, IgG1, and neutralizing antibodies (highest dilution of serum that inhibited the cytopathic effect by at least 50% [PRNT50]) were observed in the no-take group before vaccination (166 vs 94.3 ELISAU/mL [P < .05], 53.2 vs 34.5 ELISAU/mL [ P < .05], and 30% vs 19.7% [P < .05], respectively). The mean time since last smallpox vaccination was longer in the take group than in the no-take group. Total IgG, IgG subclasses, avidity index, and PRNT50 levels were higher among “take” than “no-take” volunteers 14 days after revaccination. The no-take group was not inferior to the take group in all vaccinia immune marker levels measured 24 months after vaccination. Moreover, mean interferon-γ secretion and the percentage of serum samples with PRNT50 levels ≥1:32 were significantly higher in the No-take group than in the take group (677.5 vs 282.7 pg/mL [P < .05] and 95% vs 80% [P < .05], respectively).

Conclusions. The overwhelming majority of subjects in the no-take group were successfully revaccinated against smallpox. Under circumstances of emergent smallpox mass immunization, there is no need for revaccination success assessment among individuals who have received multiple previous smallpox vaccinations.

Journal Article.  3903 words.  Illustrated.

Subjects: Infectious Diseases ; Immunology ; Public Health and Epidemiology ; Microbiology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.