Comparison of disease trends in the Ontario swine population using active practitioner-based surveillance and passive laboratory-based surveillance (2007-2009).

A concern about emerging swine diseases led to a pilot study to determine the feasibility of an active surveillance system referred to as the Ontario Swine Veterinary-based Surveillance System (OSVS). The OSVS recorded the incidence of various syndromes and investigated potential outbreaks. However, validation of the disease patterns observed was needed. The objective of this study was to compare the disease patterns observed in the OSVS system with submission data obtained from a regional diagnostic laboratory - the Animal Health Laboratory (AHL). Higher rates of submission were reported to the OSVS compared with AHL records. However, OSVS and AHL data captured similar trends of disease. The OSVS data captured potential outbreaks that were not reflected in the laboratory data. Validation of active and passive syndromic surveillance data is necessary, and efforts should be made to integrate these types of data sources.