title: Immunosuppressive treatments reduce long-term immunity to smallpox among patients with breast cancer.
abstract: BACKGROUND
  Mass vaccination is the principal preventive measure against a smallpox outbreak after an act of bioterrorism. Vaccination of subjects who received immunosuppressive therapies is problematic because of smallpox vaccine reactogenicity. Moreover, long-term immunity to vaccinia might be affected.
  
  
  OBJECTIVE
  The objective of the study was to examine the effect of cytotoxic chemotherapy on long-term immunity to vaccinia.
  
  
  METHODS
  In a case-control study, 67 patients with breast cancer who received cytotoxic chemotherapy and who were disease free for at least 1 year were matched with healthy controls according to age, sex, and the number of smallpox vaccinations received. Markers of immunity to smallpox were examined. Forty-one patients with breast cancer who did not receive chemotherapy were used to assess the affect of cancer and radiotherapy on immunity to smallpox.
  
  
  RESULTS
  Patients with breast cancer who received chemotherapy had lower levels of vaccinia total immunoglobulin G and immunoglobulin G1 (expressed as enzyme-linked immunosorbent assay units per milliliter), neutralizing antibodies, vaccinia:memory B cell ratio (expressed as a percentage), and interferon-gamma level (expressed as picograms per milliliter), compared with healthy control individuals.
  
  
  CONCLUSIONS
  Immunity to smallpox is reduced after receipt of chemotherapy for breast cancer. This finding should be considered when planning smallpox vaccination campaigns. The effect of immunosuppressive treatments on persistence of immunity should be tested with respect to additional vaccines or natural infections.
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health, Tel Aviv University, Tel Aviv, Israel. wiser@post.tau.ac.il
authors.forename: Itay
authors.initials: I
authors.lastname: Wiser
authors.forename: Nadav
authors.initials: N
authors.lastname: Orr
authors.forename: Bella
authors.initials: B
authors.lastname: Kaufman
authors.forename: Shlomo
authors.initials: S
authors.lastname: Segev
authors.forename: Zehava
authors.initials: Z
authors.lastname: Smetana
authors.forename: Ania
authors.initials: A
authors.lastname: Bialik
authors.forename: Nava
authors.initials: N
authors.lastname: Epstein
authors.forename: Ella
authors.initials: E
authors.lastname: Mendelson
authors.forename: Raphael
authors.initials: R
authors.lastname: Catane
authors.forename: Dani
authors.initials: D
authors.lastname: Cohen
mesh_terms: D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000145:classification; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D008875:Middle Aged; D012189:Retrospective Studies; D012899:Smallpox / Q000276:immunology* / Q000821:virology; D012900:Smallpox Vaccine / Q000276:immunology; D014616:Vaccinia virus / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D000970:Antineoplastic Agents; D007074:Immunoglobulin G; D007166:Immunosuppressive Agents; D012900:Smallpox Vaccine