[Enzootic pneumonia (EP) in Swiss swine herds after area-wide eradication: epidemiological analysis of outbreaks occurring between 1999 and 2003].
In a retrospective analysis, infections of swine herds with Enzootic Pneumonia (EP), occurring after the regional eradication programme had been completed, were evaluated and described according to epidemiological criteria. The aim of this study was to obtain interim results about status, progress and trends of the area-wide eradication in Switzerland over all regions involved in the programme. The population comprised pig farms with eradication of EP completed by the end of 2002. Incidence of EP infection was calculated for the years 2000-2003. Seasonal effects, influences from production-type, herd size, and pig density in the surrounding area on incidences of EP outbreaks were investigated. In 2000-2002, annual incidences were steadily decreasing from 3.1% to 2.0%, and they showed great regional variation. In 2003, contrary to the long-term trend, a minor increase of overall incidence from 2.0% to 2.1% was observed while the incidence for breeding-only farms continued to recede. Possible explanations for this are discussed. Previous observations on EP infections accumulating in the cold season could not be confirmed. Large farms, finishing farms, and farms located in densely populated pig areas as well as farms being part of multisite production rings had a higher risk of infection. In spite of occurrence of EP outbreaks in eradicated areas, the current status of the area-wide eradication is promising, and a further decline in incidence of EP infection can be expected in the future.
Zellweger
K
K
Bundesamt für Veterinärwesen, Bern. Karola.Zellweger@itn.unibe.ch
Stärk
K D C
KD
Rüfenacht
J
J
D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D004196:Disease Outbreaks / Q000662:veterinary*; D005260:Female; D008297:Male; D045729:Pneumonia of Swine, Mycoplasmal / Q000453:epidemiology* / Q000517:prevention & control*; D011156:Population Density; D015397:Program Evaluation; D012189:Retrospective Studies; D012307:Risk Factors; D012621:Seasons; D013552:Swine; D013557:Switzerland / Q000453:epidemiology