title: Effectiveness of porcine circovirus type 2 vaccination in reducing the severity of post-weaning multisystemic wasting syndrome in pigs.
abstract: Changes in the severity of post-weaning multisystemic wasting syndrome (PMWS) and the effect of vaccination against porcine circovirus type 2 (PCV2) on the severity of PMWS and the prevalence of PCV2 were assessed on 50 English pig farms from 2008 to 2010. PMWS severity on farms before and after PCV2 vaccination was estimated by combining data on post-weaning mortality, morbidity and proportion of pigs positive for PCV2 by PCR. At the first visit (before vaccination), all 50 farms were seropositive for PCV2 and 90% of farms were positive for PCV2 by PCR. At the second visit (331-539 days after the first visit), all 50 farms remained seropositive for PCV2 and 28/50 (56%) were positive for PCV2 by PCR, representing 16/36 (44.4%) farms that vaccinated against PCV2 and 12/14 (85.7%) farms that did not. There was a reduction of ~50% in mean PMWS score on farms that vaccinated and were initially moderately or highly PMWS affected. Vaccination against PCV2 reduced the severity of PMWS, even though PCV2 persisted on 44% of farms after vaccination.
authors.affiliation: Department of Production and Population Health, The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK. Electronic address: mvelasova@rvc.ac.uk.
authors.forename: Martina
authors.initials: M
authors.lastname: Velasova
authors.forename: Pablo
authors.initials: P
authors.lastname: Alarcon
authors.forename: Dirk
authors.initials: D
authors.lastname: Werling
authors.forename: Amanda
authors.initials: A
authors.lastname: Nevel
authors.forename: Barbara
authors.initials: B
authors.lastname: Wieland
mesh_terms: D000818:Animals; D017925:Circovirus / Q000276:immunology*; D003430:Cross-Sectional Studies; D004739:England; D053570:Porcine Postweaning Multisystemic Wasting Syndrome / Q000453:epidemiology / Q000517:prevention & control* / Q000821:virology; D015995:Prevalence; D013552:Swine; D014611:Vaccination; D014765:Viral Vaccines / Q000276:immunology*
chemical_list: D014765:Viral Vaccines
keywords: Epidemiology; Porcine circovirus type 2; Post-weaning multisystemic wasting syndrome; Vaccination