title: Residents had an increasing risk of norovirus gastroenteritis infection than health care workers during an outbreak in a nursing home.
abstract: OBJECTIVE
  To study norovirus gastroenteritis infection among residents and health care workers (HCWs) during an outbreak in a nursing home by investigating the attack rate and positive diagnostic rate for norovirus by reverse transcription-polymerase chain reaction (RT-PCR).
  
  
  METHODS
  All members in a Chang Gung Memorial Hospital-affiliated nursing home from November 17, 2006, to November 25, 2006, including 236 residents and 125 HCWs, whose available medical records were available were consecutively included in the retrospective analysis. Fecal specimens of symptomatic residents and HCWs were tested for norovirus by RT-PCR. In addition, routine stool analysis and a stool culture study were conducted to identify the bacterial and parasitic agents. The fecal specimens of asymptomatic residents and HCWs were tested only for norovirus by RT-PCR.
  
  
  RESULTS
  The outbreak was controlled within 9 days during the outbreak period. There were 51 symptomatic cases, 41 residents and 10 HCWs, during the norovirus outbreak. The odds ratio (OR) of the attack rate in the residents was approximately 2.4 times higher than that in the HCWs (OR: 2.4; 95% confidence interval [CI]: 1.2-5.0; P = .015). Norovirus was detected in 59 (30.6%) of 193 residents and in 11 (10.5%) of 105 HCWs who provided stool specimens for the study by RT-PCR. The OR of the positive diagnostic rate for norovirus by RT-PCR in the residents was approximately 3.8 times higher than that in the HCWs (OR: 3.8; 95% CI: 1.9-7.5; P < .001).
  
  
  CONCLUSIONS
  During an outbreak of norovirus gastroenteritis in a nursing home, the infection can be easily transmitted from person to person and affects both residents and HCWs. In addition, residents had a higher risk of norovirus gastroenteritis infection than HCWs.
authors.affiliation: Infection Control Committee, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Li-Chu
authors.initials: LC
authors.lastname: Yang
authors.forename: Ping-Cherng
authors.initials: PC
authors.lastname: Chiang
authors.forename: Tzu-Hsin
authors.initials: TH
authors.lastname: Huang
authors.forename: Su-Fen
authors.initials: SF
authors.lastname: Chi
authors.forename: Yueh-Pi
authors.initials: YP
authors.lastname: Chiu
authors.forename: Chun-Sui
authors.initials: CS
authors.lastname: Lin
authors.forename: Yen-Fang
authors.initials: YF
authors.lastname: Chou
authors.forename: Su-Chu
authors.initials: SC
authors.lastname: Hsu
authors.forename: Xiu-Se
authors.initials: XS
authors.lastname: Zhang
authors.forename: Chung-Guei
authors.initials: CG
authors.lastname: Huang
authors.forename: Chen-Yi
authors.initials: CY
authors.lastname: Kao
authors.forename: Chih-Ming
authors.initials: CM
authors.lastname: Lin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004196:Disease Outbreaks; D018562:Disease Transmission, Infectious / Q000517:prevention & control; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology* / Q000209:etiology; D006282:Health Personnel; D006801:Humans; D008297:Male; D008875:Middle Aged; D029322:Norovirus / Q000235:genetics / Q000472:pathogenicity*; D009735:Nursing Homes; D016017:Odds Ratio; D010361:Patients; D016133:Polymerase Chain Reaction; D018570:Risk Assessment; D017422:Sequence Analysis, DNA; D013624:Taiwan / Q000453:epidemiology