title: [Legionella spp. contamination in indoor air: preliminary results of an Italian multicenter study].
abstract: OBJECTIVE
  To propose a standardized protocol for the evaluation of Legionella contamination in air.
  
  
  METHODS
  A bathroom having a Legionella contamination in water >1,000 cfu/l was selected in 10 different healthcare facilities. Air contamination was assessed by active (Surface Air System, SAS) and passive (Index of Microbial Air, IMA) sampling for 8 hours, about 1 m away from the floor and 50 cm from the tap water. Two hundred liters of air were sampled by SAS every 12 min, after flushing water for 2 min. The IMA value was calculated as the mean value of colony forming units/16 plates exposed during sampling (2 plates/hour). Water contamination was evaluated at T0, after 4 and 8 hours, according to the standard methods.
  
  
  RESULTS
  Air contamination by Legionella was found in three healthcare facilities (one with active and two with passive sampling), showing a concomitant tap water contamination (median=40,000; range 1,100-43,000 cfu/l). The remaining seven hospitals isolated Legionella spp. exclusively from water samples (median=8,000; range 1,200-70,000 cfu/l).
  
  
  CONCLUSIONS
  Our data suggest that environmental Legionella contamination cannot be assessed only through the air sampling, even in the presence of an important water contamination.
authors.affiliation: Dipartimento di scienze biomediche e oncologia umana, Sezione di igiene, Università degli studi di Bari "Aldo Moro". igiene.dimo@uniba.it.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Montagna
authors.forename: Osvalda
authors.initials: O
authors.lastname: De Giglio
authors.forename: Christian
authors.initials: C
authors.lastname: Napoli
authors.forename: Lucia
authors.initials: L
authors.lastname: Cannova
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Cristina
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Deriu
authors.forename: Santi Antonino
authors.initials: SA
authors.lastname: Delia
authors.forename: Ada
authors.initials: A
authors.lastname: Giuliano
authors.forename: Marco
authors.initials: M
authors.lastname: Guida
authors.forename: Pasqualina
authors.initials: P
authors.lastname: Laganà
authors.forename: Giorgio
authors.initials: G
authors.lastname: Liguori
authors.forename: Ida
authors.initials: I
authors.lastname: Mura
authors.forename: Francesca
authors.initials: F
authors.lastname: Pennino
authors.forename: Angelo
authors.initials: A
authors.lastname: Rossini
authors.forename: Stefano
authors.initials: S
authors.lastname: Tardivo
authors.forename: Ida
authors.initials: I
authors.lastname: Torre
authors.forename: Maria Valeria
authors.initials: MV
authors.lastname: Torregrossa
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Villafrate
authors.forename: Roberto
authors.initials: R
authors.lastname: Albertini
authors.forename: Cesira
authors.initials: C
authors.lastname: Pasquarella
mesh_terms: D000391:Air Microbiology; D016902:Air Pollution, Indoor; D015373:Bacterial Typing Techniques; D003428:Cross Infection / Q000517:prevention & control; D004784:Environmental Monitoring / Q000379:methods / Q000592:standards; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D007558:Italy; D007875:Legionella / Q000145:classification / Q000254:growth & development / Q000302:isolation & purification*; D007876:Legionellosis / Q000517:prevention & control; D014038:Toilet Facilities; D014865:Waste Disposal, Fluid; D014871:Water Microbiology