title: Prevention of nosocomial transmission of norovirus by strategic infection control measures.
abstract: BACKGROUND
  Nosocomial outbreaks of norovirus infection pose a great challenge to the infection control team.
  
  
  METHODS
  Between November 1, 2009, and February 28, 2010, strategic infection control measures were implemented in a hospital network. In addition to timely staff education and promotion of directly observed hand hygiene, reverse-transcription polymerase chain reaction for norovirus was performed as an added test by the microbiology laboratory for all fecal specimens irrespective of the request for testing. Laboratory-confirmed cases were followed up by the infection control team for timely intervention. The incidence of hospital-acquired norovirus infection per 1,000 potentially infectious patient-days was compared with the corresponding period in the preceding 12 months, and the incidence in the other 6 hospital networks in Hong Kong was chosen as the concurrent control. Phylogenetic analysis of norovirus isolates was performed.
  
  
  RESULTS
  Of the 988 patients who were tested, 242 (25%) were positive for norovirus; 114 (47%) of those 242 patients had norovirus detected by our added test. Compared with the corresponding period in the preceding 12 months, the incidence of hospital-acquired norovirus infection decreased from 131 to 16 cases per 1,000 potentially infectious patient-days (P < .001), although the number of hospital-acquired infections was low in both the study period (n = 8) and the historical control periods (n = 11). The incidence of hospital-acquired norovirus infection in our hospital network (0.03 cases per 1,000 patient-days) was significantly lower than that of the concurrent control (0.06 cases per 1,000 patient-days) (P = .015). Forty-three (93%) of 46 norovirus isolates sequenced belonged to the genogroup II.4 variant.
  
  
  CONCLUSIONS
  Strategic infection control measures with an added test may be useful in controlling nosocomial transmission of norovirus.
authors: Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China.
authors: Vincent C C
authors: VC
authors: Cheng
authors: Lisa M W
authors: LM
authors: Wong
authors: Josepha W M
authors: JW
authors: Tai
authors: Jasper F W
authors: JF
authors: Chan
authors: Kelvin K W
authors: KK
authors: To
authors: Iris W S
authors: IW
authors: Li
authors: Ivan F N
authors: IF
authors: Hung
authors: K H
authors: KH
authors: Chan
authors: P L
authors: PL
authors: Ho
authors: K Y
authors: KY
authors: Yuen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017250:Caliciviridae Infections / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission; D002648:Child; D002675:Child, Preschool; D003428:Cross Infection / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission; D004279:DNA, Viral / Q000032:analysis; D004196:Disease Outbreaks / Q000517:prevention & control* / Q000706:statistics & numerical data; D005260:Female; D006235:Hand Disinfection; D006723:Hong Kong; D006785:Hospitals, University; D006801:Humans; D015994:Incidence; D007223:Infant; D017053:Infection Control / Q000379:methods*; D008297:Male; D008875:Middle Aged; D029322:Norovirus / Q000235:genetics / Q000302:isolation & purification*; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055815:Young Adult
chemical_list: D004279:DNA, Viral