title: Unintentional transfer of vaccinia virus associated with smallpox vaccines: ACAM2000(®) compared with Dryvax(®).
abstract: BACKGROUND
  Routine vaccination against smallpox (variola) ceased in the US in 1976. However, in 2002 limited coverage for military personnel and some healthcare workers was reinstituted. In March 2008, ACAM2000® replaced Dryvax® as the vaccine used in the United States against smallpox. Unintentional transfer of vaccinia virus from a vaccination site by autoinoculation or contact transmission, can have significant public health implications. We summarize unintentional virus transfer AEs associated with ACAM2000® since March 2008 and compare with Dryvax®.
  
  
  RESULTS
  We identified 309 reports for ACAM2000® with skin or ocular involvement, of which 93 were autoinoculation cases and 20 were contact transmission cases. The rate for reported cases of autoinoculation was 20.6 per 100,000 vaccinations and for contact transmission was 4.4 per 100,000 vaccinations. Eighteen contact transmission cases could be attributed to contact during a sporting activity (45%) or intimate contact (45%). Of the 113 unintentional transfer cases, 6 met the case definition for ocular vaccinia. The most common locations for all autoinoculation and contact cases were arm/elbow/shoulder (35/113; 31%) and face (24/113; 21%). Methods We reviewed 753 reports associated with smallpox in the Vaccine Adverse Event Reporting System and CDC Poxvirus consultation log, reported from March 2008 to August 2010. Reports were classified into categories based upon standard case definitions.
  
  
  CONCLUSIONS
  Overall, unintentional transfer events for ACAM2000® and Dryvax® are similar. We recommend continued efforts to prevent transfer events and continuing education for healthcare providers focused on recognition of vaccinia lesions, proper sample collection, and laboratory testing to confirm diagnosis.
authors.affiliation: Poxvirus and Rabies Branch; Centers for Disease Control and Prevention; Atlanta, GA USA; Epidemic Intelligence Service; Centers for Disease Control and Prevention; Atlanta, GA USA.
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Tack
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Karem
authors.forename: Jay R
authors.initials: JR
authors.lastname: Montgomery
authors.forename: Limone
authors.initials: L
authors.lastname: Collins
authors.forename: Marthe G
authors.initials: MG
authors.lastname: Bryant-Genevier
authors.forename: Rosemary
authors.initials: R
authors.lastname: Tiernan
authors.forename: Maria
authors.initials: M
authors.lastname: Cano
authors.forename: Paige
authors.initials: P
authors.lastname: Lewis
authors.forename: Renata J M
authors.initials: RJ
authors.lastname: Engler
authors.forename: Inger K
authors.initials: IK
authors.lastname: Damon
authors.forename: Mary G
authors.initials: MG
authors.lastname: Reynolds
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006282:Health Personnel; D006801:Humans; D008297:Male; D008875:Middle Aged; D008889:Military Personnel; D011358:Product Surveillance, Postmarketing; D012899:Smallpox / Q000517:prevention & control*; D012900:Smallpox Vaccine / Q000008:administration & dosage / Q000009:adverse effects*; D014481:United States; D014611:Vaccination / Q000009:adverse effects*; D014615:Vaccinia / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission*; D014616:Vaccinia virus / Q000302:isolation & purification*; D055815:Young Adult
chemical_list: C000588544:ACAM2000; C078786:DryVax vaccine; D012900:Smallpox Vaccine
keywords: Orthopoxvirus; adverse events; autoinoculation; contact vaccinia; smallpox vaccine; vaccinia virus