title: Risk factors for pandemic (H1N1) 2009 virus seroconversion among hospital staff, Singapore.
abstract: We describe incidence and risk factors for pandemic (H1N1) 2009 virus infection in healthcare personnel during the June-September 2009 epidemic in Singapore. Personnel contributed 3 serologic samples during June-October 2009, with seroconversion defined as a ≥4-fold increase in hemagglutination inhibition titers to pandemic (H1N1) 2009. Of 531 participants, 35 showed evidence of seroconversion. Seroconversion rates were highest in nurses (28/290) and lowest in allied health staff (2/116). Significant risk factors on multivariate analysis were being a nurse (adjusted odds ratio [aOR] 4.5, 95% confidence interval [CI] 1.0-19.6) and working in pandemic (H1N1) 2009 isolation wards (aOR 4.5, 95% CI 1.3-15.6). Contact with pandemic (H1N1) 2009-infected colleagues (aOR 2.5, 95% CI 0.9-6.6) and larger household size (aOR 1.2, 95% CI 1.0-1.4) were of borderline significance. Our study suggests that seroconversion was associated with occupational and nonoccupational risk factors.
authors.affiliation: Department of Clinical Epidemiology, Tan Tock Seng Hospital, Singapore. mark_ic_chen@ttsh.com.sg
authors.forename: Mark I C
authors.initials: MI
authors.lastname: Chen
authors.forename: Vernon J M
authors.initials: VJ
authors.lastname: Lee
authors.forename: Ian
authors.initials: I
authors.lastname: Barr
authors.forename: Cui
authors.initials: C
authors.lastname: Lin
authors.forename: Rachelle
authors.initials: R
authors.lastname: Goh
authors.forename: Caroline
authors.initials: C
authors.lastname: Lee
authors.forename: Baldev
authors.initials: B
authors.lastname: Singh
authors.forename: Jessie
authors.initials: J
authors.lastname: Tan
authors.forename: Wei Yen
authors.initials: WY
authors.lastname: Lim
authors.forename: Alex R
authors.initials: AR
authors.lastname: Cook
authors.forename: Brenda
authors.initials: B
authors.lastname: Ang
authors.forename: Angela
authors.initials: A
authors.lastname: Chow
authors.forename: Boon Huan
authors.initials: BH
authors.lastname: Tan
authors.forename: Jimmy
authors.initials: J
authors.lastname: Loh
authors.forename: Robert
authors.initials: R
authors.lastname: Shaw
authors.forename: Kee Seng
authors.initials: KS
authors.lastname: Chia
authors.forename: Raymond T P
authors.initials: RT
authors.lastname: Lin
authors.forename: Yee Sin
authors.initials: YS
authors.lastname: Leo
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D015994:Incidence; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007251:Influenza, Human / Q000453:epidemiology* / Q000276:immunology; D008297:Male; D016273:Occupational Exposure; D058873:Pandemics; D010564:Personnel, Hospital; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012846:Singapore / Q000453:epidemiology
chemical_list: D000914:Antibodies, Viral