Risk factors for Actinobacillus pleuropneumoniae serotype 2 infection in Danish genetic specific pathogen-free pig herds.
Between 1994 and 1998, 297 genetic specific pathogen-free (spf) pig herds participated in a monthly clinical and serological monitoring programme for infection with Actinobacillus pleuropneumoniae serotype 2 (ap-2). The average annual herd-level incidence was 3.4 per cent but there was a significant decreasing trend. A risk index, summing up the exposure from ap-2-infected neighbouring pigs within a 3 km radius, was derived from a geographical information system. A survival analysis indicates that the risk of ap-2 infection increased in proportion to the risk index, suggesting that local spread of ap-2 from infected neighbours was a significant factor. However, herd-specific purchase policies were not apparently associated with the risk of ap-2 infection.
Zhuang
Q
Q
Danish Bacon and Meat Council, Axelborg, Axeltorv 3, dk-1609 Copenhagen V, Denmark.
Barfod
K
K
Wachmann
H
H
Mortensen
S
S
Lavritsen
D T
DT
Ydesen
B
B
Willeberg
P
P
D000189:Actinobacillus Infections / Q000453:epidemiology / Q000662:veterinary*; D016977:Actinobacillus pleuropneumoniae / Q000145:classification / Q000302:isolation & purification; D000704:Analysis of Variance; D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D003718:Denmark; D005260:Female; D015994:Incidence; D008297:Male; D016016:Proportional Hazards Models; D012307:Risk Factors; D012703:Serotyping; D013047:Specific Pathogen-Free Organisms; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology*