title: Anaphylaxis following quadrivalent human papillomavirus vaccination.
abstract: BACKGROUND
  In 2007, Australia implemented the National human papillomavirus (HPV) Vaccination Program, which provides quadrivalent HPV vaccine free to all women aged 12-26 years. Following notification of 7 presumptive cases of anaphylaxis in the state of New South Wales, Australia, we verified cases and compared the incidence of anaphylaxis following HPV vaccination to other vaccines in comparable settings.
  
  
  METHODS
  We contacted all patients with suspected anaphylaxis and obtained detailed histories from telephone interviews and a review of medical records. A multidisciplinary team determined whether each suspected case met the standardized Brighton definition. Some participants also received skin-prick allergy testing for common antigens and components of the HPV vaccine.
  
  
  RESULTS
  Of 12 suspected cases, 8 were classified as anaphylaxis. Of these, 4 participants had negative skin-prick test results for intradermal Gardasil. From the 269 680 HPV vaccine doses administered in schools, 7 cases of anaphylaxis were identified, which represents an incidence rate of 2.6 per 100 000 doses (95% CI 1.0-5.3 per 100 000). In comparison, the rate of identified anaphylaxis was 0.1 per 100 000 doses (95% CI 0.003-0.7) for conjugated meningococcal C vaccination in a 2003 school-based program.
  
  
  CONCLUSIONS
  Based on the number of confirmed cases, the estimated rate of anaphylaxis following quadrivalent HPV vaccine was significantly higher than identified in comparable school-based delivery of other vaccines. However, overall rates were very low and managed appropriately with no serious sequelae.
authors.affiliation: National Centre for Immunisation Research and Surveillance, The Children's Hospital at Westmead and University of Sydney, NSW, Australia. juliab2@chw.edu.au
authors.forename: Julia M L
authors.initials: JM
authors.lastname: Brotherton
authors.forename: Mike S
authors.initials: MS
authors.lastname: Gold
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Kemp
authors.forename: Peter B
authors.initials: PB
authors.lastname: McIntyre
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Burgess
authors.forename: Sue
authors.initials: S
authors.lastname: Campbell-Lloyd