A recent outbreak of Actinobacillus pleuropneumoniae (APP) has been impacting pig farms across the upper Midwest since November. Evaluation shows the outbreaks are all APP type 15, in areas that had previously been well controlled.

Affected sites have been late finishing phase animals prior to marketing activities. Rapid infection transforms the sites from healthy animals one moment, to visible outbreak followed by extremely high mortality as quickly as overnight. APP is an obligate parasite and veterinarians in affected areas report not having vaccines on hand, as the outbreaks have been a surprise.

Read more on APP symptoms, transmission and prevention here.