title: Outbreak of novel influenza A (H1N1-2009) linked to a dance club.
abstract: BACKGROUND
  This paper describes the epidemiology and control of a community outbreak of novel influenza A (H1N1-2009) originating from a dance club in Singapore between June and July 2009.
  
  
  METHODS
  Cases of novel influenza A (H1N1-2009) were confirmed using in-house probe-based real-time polymerase chain reaction (PCR). Contact tracing teams from the Singapore Ministry of Health obtained epidemiological information from all cases via telephone.
  
  
  RESULTS
  A total of 48 cases were identified in this outbreak, of which 36 (75%) cases were patrons and dance club staff, and 12 (25%) cases were household members and social contacts. Mathematical modelling showed that this outbreak had a reproductive number of 1.9 to 2.1, which was similar to values calculated from outbreaks in naïve populations in other countries.
  
  
  CONCLUSIONS
  This transmission risk occurred within an enclosed space with patrons engaged in intimate social activities, suggesting that dance clubs are places conducive for the spread of the virus.
authors.affiliation: Communicable Diseases Division, Ministry of Health, Singapore. chan_pei_pei@moh.gov.sg
authors.forename: Pei Pei
authors.initials: PP
authors.lastname: Chan
authors.forename: Hariharan
authors.initials: H
authors.lastname: Subramony
authors.forename: Florence Y L
authors.initials: FY
authors.lastname: Lai
authors.forename: Wee Siong
authors.initials: WS
authors.lastname: Tien
authors.forename: Boon Hian
authors.initials: BH
authors.lastname: Tan
authors.forename: Suhana
authors.initials: S
authors.lastname: Solhan
authors.forename: Hwi Kwang
authors.initials: HK
authors.lastname: Han
authors.forename: Bok Huay
authors.initials: BH
authors.lastname: Foong
authors.forename: Lyn
authors.initials: L
authors.lastname: James
authors.forename: Peng Lim
authors.initials: PL
authors.lastname: Ooi
mesh_terms: D000293:Adolescent; D000328:Adult; D003132:Commerce; D016358:Contact Tracing / Q000379:methods*; D003615:Dancing; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification*; D007251:Influenza, Human / Q000175:diagnosis / Q000453:epidemiology*; D007407:Interviews as Topic; D008297:Male; D015233:Models, Statistical; D016133:Polymerase Chain Reaction; D012846:Singapore / Q000453:epidemiology; D014195:Travel; D055815:Young Adult