title: Evaluation of the long-term effect of air filtration on the occurrence of new PRRSV infections in large breeding herds in swine-dense regions.
abstract: Airborne transmission of porcine reproductive and respiratory syndrome virus (PRRSV) is a risk factor for the infection of susceptible populations. Therefore, a long‑term sustainability study of air filtration as a means to reduce this risk was conducted. Participating herds (n = 38) were organized into 4 independent cohorts and the effect of air filtration on the occurrence of new PRRSV infections was analyzed at 3 different levels from September 2008 to January 2012 including the likelihood of infection in contemporary filtered and non-filtered herds, the likelihood of infection before and after implementation of filtration and the time to failure in filtered and non-filtered herds. Results indicated that new PRRSV infections in filtered breeding herds were significantly lower than in contemporary non-filtered control herds (P < 0.01), the odds for a new PRRSV infection in breeding herds before filtration was 7.97 times higher than the odds after filtration was initiated (P < 0.01) and the median time to new PRRSV infections in filtered breeding herds of 30 months was significantly longer than the 11 months observed in non-filtered herds (P < 0.01). In conclusion, across all 3 levels of analysis, the long-term effect of air filtration on reducing the occurrence of new PRRSV infections in the study population was demonstrated.
authors: Pipestone Veterinary Clinic, Pipestone, MN 56164, USA. sdee@pipevet.com
authors: Scott
authors: S
authors: Dee
authors: Jean Paul
authors: JP
authors: Cano
authors: Gordon
authors: G
authors: Spronk
authors: Darwin
authors: D
authors: Reicks
authors: Paul
authors: P
authors: Ruen
authors: Andrea
authors: A
authors: Pitkin
authors: Dale
authors: D
authors: Polson
mesh_terms: D000391:Air Microbiology; D000818:Animals; D004203:Disinfection / Q000379:methods*; D005374:Filtration / Q000379:methods*; D017053:Infection Control / Q000379:methods*; D019318:Porcine Reproductive and Respiratory Syndrome / Q000517:prevention & control* / Q000635:transmission; D019316:Porcine respiratory and reproductive syndrome virus / Q000302:isolation & purification* / Q000472:pathogenicity; D013552:Swine; D013997:Time Factors