Challenges to implementing second-dose varicella vaccination during an outbreak in the absence of a routine 2-dose vaccination requirement--Maine, 2006.
In June 2005, the Advisory Committee on Immunization Practices (ACIP) recommended administering a second dose of varicella vaccine during outbreaks, supplementing the routine 1-dose requirement. From October 2005 to January 2006, a varicella outbreak occurred in Maine in a highly vaccinated elementary school population. We investigated the outbreak, held a school-based vaccination clinic, and assessed costs in implementing ACIP's outbreak-response recommendation. Parents completed questionnaires and case investigation interviews. Personnel at the Maine Center for Disease Control and Prevention, the school in which the outbreak occurred ("school A"), and physician offices completed economic surveys. Forty-eight cases occurred, with no hospitalizations or deaths. Vaccine effectiveness was 86.6% (95% confidence interval, 82.0%-90.1%). Of 240 eligible students, 132 (55.0%) received second-dose vaccination. Implementing ACIP's outbreak-response recommendation was challenging and cost approximately $26,875. Additionally, the routine 1-dose varicella vaccination policy did not confer adequate population immunity to prevent this outbreak. These findings support ACIP's June 2007 recommendation for a routine 2-dose varicella vaccination program.
Parker
Amy A
AA
Epidemic Intelligence Service, Epidemiology Program Office, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA. AParker@cdc.gov
Reynolds
Meredith A
MA
Leung
Jessica
J
Anderson
Meredith
M
Rey
Araceli
A
Ortega-Sanchez
Ismael R
IR
Schmid
D Scott
DS
Guris
Dalya
D
Gensheimer
Kathleen F
KF
D002644:Chickenpox / Q000453:epidemiology* / Q000503:physiopathology / Q000517:prevention & control*; D019433:Chickenpox Vaccine / Q000008:administration & dosage* / Q000191:economics; D002648:Child; D004196:Disease Outbreaks / Q000517:prevention & control*; D005260:Female; D006801:Humans; D017589:Immunization Programs / Q000191:economics; D007115:Immunization Schedule; D007407:Interviews as Topic; D008281:Maine / Q000453:epidemiology; D008297:Male; D012574:Schools; D011795:Surveys and Questionnaires; D014611:Vaccination / Q000191:economics
D019433:Chickenpox Vaccine