title: Nonclassic measles infections in an immune population exposed to measles during a college bus trip.
abstract: This study investigated the frequency of mild or asymptomatic measles infections among 44 persons exposed to a student with measles during a 3-day bus trip using two buses. Questionnaires and serum samples were obtained 26-37 days after the trip. All participants had detectable measles-neutralizing antibodies, and none developed classic measles symptoms. Ten persons (23%) were IgM positive for measles, indicating recent infection. Among previously vaccinated IgM-negative persons, those who rode on bus A with the index case-patient had significantly higher microneutralization titers than those on bus B (P= .001), suggesting that some persons on bus A were infected but were IgM negative at the time of the study. Mild or asymptomatic measles infections are probably very common among measles-immune persons exposed to measles cases and may be the most common manifestation of measles during outbreaks in highly immune populations.
authors.affiliation: Emory University, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Atlanta, Georgia, USA.
authors.forename: R F
authors.initials: RF
authors.lastname: Helfand
authors.forename: D K
authors.initials: DK
authors.lastname: Kim
authors.forename: H E
authors.initials: HE
authors.lastname: Gary
authors.forename: G L
authors.initials: GL
authors.lastname: Edwards
authors.forename: G P
authors.initials: GP
authors.lastname: Bisson
authors.forename: M J
authors.initials: MJ
authors.lastname: Papania
authors.forename: J L
authors.initials: JL
authors.lastname: Heath
authors.forename: D L
authors.initials: DL
authors.lastname: Schaff
authors.forename: W J
authors.initials: WJ
authors.lastname: Bellini
authors.forename: S C
authors.initials: SC
authors.lastname: Redd
authors.forename: L J
authors.initials: LJ
authors.lastname: Anderson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood; D004196:Disease Outbreaks; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008457:Measles / Q000453:epidemiology* / Q000276:immunology* / Q000473:pathology; D008458:Measles Vaccine / Q000276:immunology*; D008459:Measles virus / Q000276:immunology*; D008875:Middle Aged
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008458:Measles Vaccine