title: An outbreak of norovirus infection in a long-term-care unit in Spain.
abstract: BACKGROUND
  Norovirus belongs to the Caliciviridae family and causes outbreaks of infectious enteritis by fecal-oral transmission. In Spain, there have been few outbreaks reported due to this virus. We describe an outbreak on a long-term-care hospital ward.
  
  
  METHODS
  Cases were classified as probable, confirmed, and secondary. Stool cultures were performed. Polymerase chain reaction detection of norovirus was also performed.
  
  
  RESULTS
  The outbreak occurred from December 7 to 28, 2001, involving 60 cases (32 patients, 19 staff members, 8 patients' relatives, and 1 relative of a staff member). Most (82%) of the cases were female. The most frequently involved ages were 20 to 39 years for staff members and 70 to 89 years for patients. The incubation period of secondary cases in patients' families had a median of 48 hours (range, 1 to 7 days). Clinical symptoms included diarrhea (85%), vomiting (75%), fever (37%), nausea (23%), and abdominal pain (12%). Median duration of the disease was 48 hours (range, 1 to 7 days). All cases resolved and the outbreak halted with additional hygienic measures. Stool cultures were all negative for enteropathogenic bacteria and rotaviruses. In 16 of 23 cases, the norovirus genotype 2 antigen was detected.
  
  
  CONCLUSIONS
  This outbreak of gastroenteritis due to norovirus genotype 2 affected patients, staff members, and their relatives in a long-term-care facility and was controlled in 21 days.
authors.affiliation: Unitat d'Epidemiologia I Avaluacio, Corporacio Parc Tauli, Parc Tauli s/n, 08208 Sabadell, Barcelona, Spain. gnavarro@cspt.es
authors.forename: Gemma
authors.initials: G
authors.lastname: Navarro
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Sala
authors.forename: Ferran
authors.initials: F
authors.lastname: Segura
authors.forename: César
authors.initials: C
authors.lastname: Arias
authors.forename: Esperanza
authors.initials: E
authors.lastname: Anton
authors.forename: Pilar
authors.initials: P
authors.lastname: Varela
authors.forename: Pilar
authors.initials: P
authors.lastname: Peña
authors.forename: Teresa
authors.initials: T
authors.lastname: Llovet
authors.forename: Isabel
authors.initials: I
authors.lastname: Sanfeliu
authors.forename: Maria
authors.initials: M
authors.lastname: Canals
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Serrate
authors.forename: Antonio
authors.initials: A
authors.lastname: Nogueras
mesh_terms: D017250:Caliciviridae Infections / Q000175:diagnosis / Q000453:epidemiology / Q000635:transmission*; D003428:Cross Infection / Q000517:prevention & control / Q000821:virology*; D004196:Disease Outbreaks; D005243:Feces / Q000821:virology; D005260:Female; D005759:Gastroenteritis / Q000517:prevention & control / Q000821:virology; D006761:Hospitals; D006801:Humans; D017758:Infectious Disease Transmission, Patient-to-Professional; D008134:Long-Term Care; D008297:Male; D029322:Norovirus / Q000302:isolation & purification*; D013030:Spain / Q000453:epidemiology