title: Evaluation of an expanded case definition for vaccine-modified measles in a school outbreak in South Korea in 2010.
abstract: In this study, we have described the clinical characteristics of vaccine-modified measles  to assess the performance of an expanded case definition in a school outbreak that occurred in 2010. The  sensitivity, specificity, and the positive and negative predictive values were evaluated. Among 74 cases of  vaccine-modified measles, 47 (64%) met the original case definition. Fever and rash were observed in 73%  (54/74); fever was the most common (96%, 71/74) presenting symptom, and rash was noted in 77% (57/74) of  the cases. The original case definition showed an overall sensitivity of 63.5% and a specificity of 100.0%.  The expanded case definition combining fever and rash showed a higher sensitivity (72.9%) but a lower  specificity (88.2%) than the original. The presence of fever and one or more of cough, coryza, or  conjunctivitis scored the highest sensitivity among the combinations of signs and symptoms (77.0%), but  scored the lowest specificity (52.9%). The expanded case definition was sensitive in identifying suspected  cases of vaccine-modified measles. We suggest using this expanded definition for outbreak investigation in  a closed community, and consider further discussions on expanding the case definition of measles for  routine surveillance in South Korea.
authors.affiliation: Korea Centers for Disease Control and Prevention, Chungcheongbuk-do, Republic of Korea. choeyj@yahoo.com
authors.forename: Young June
authors.initials: YJ
authors.lastname: Choe
authors.forename: Jae Kyung
authors.initials: JK
authors.lastname: Hu
authors.forename: Kyung Min
authors.initials: KM
authors.lastname: Song
authors.forename: Heeyeon
authors.initials: H
authors.lastname: Cho
authors.forename: Hee Sook
authors.initials: HS
authors.lastname: Yoon
authors.forename: Seung Tae
authors.initials: ST
authors.lastname: Kim
authors.forename: Han Jung
authors.initials: HJ
authors.lastname: Lee
authors.forename: Kisoon
authors.initials: K
authors.lastname: Kim
authors.forename: Geun-Ryang
authors.initials: GR
authors.lastname: Bae
authors.forename: Jong-Koo
authors.initials: JK
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000914:Antibodies, Viral / Q000032:analysis; D004196:Disease Outbreaks; D006801:Humans; D008297:Male; D008457:Measles / Q000453:epidemiology* / Q000821:virology*; D008458:Measles Vaccine / Q000008:administration & dosage* / Q000009:adverse effects; D018103:Morbillivirus / Q000187:drug effects* / Q000276:immunology / Q000302:isolation & purification; D056910:Republic of Korea / Q000453:epidemiology; D012574:Schools; D012680:Sensitivity and Specificity
chemical_list: D000914:Antibodies, Viral; D008458:Measles Vaccine