Davor Ojkic, Tanya Rossi, Rebecca Egan
Animal Health Laboratory, University of Guelph, Guelph, ON.
AHL Newsletter 2026;30(2):13.
In late 2025 and early 2026, there was a spike in the number of cases of porcine epidemic diarrhea virus (PEDV) in Ontario, as reported by Swine Health Ontario (SHO), with a range of 20 to 34 new cases per month from December to February. During that same time, there were also several porcine deltacoronavirus (PDCoV) detections, ranging from 1 to 6 new cases per month. The AHL PCR data reflects this recent increase, with a total of 122 PEDV-positive submissions and 22 PDCoV-positive submissions so far this year. Over the last 5 years, the number of PEDV-positive submissions at the AHL has increased annually, and the number of PDCoV-positive submissions has also been trending upward over this period (Table 1).
Table 1. Annual PCR-positive submissions for PEDV and PDCoV at AHL*.
+ Partial year consists of Jan-May submissions
PEDV spreads rapidly and illness is characterized by a sudden onset of profuse watery diarrhea in nursing piglets, accompanied by vomiting and rapid dehydration with high morbidity and mortality rates. In nursery pigs, morbidity rates can be high, but with less severe diarrhea, dehydration, lethargy, and reduced feed intake, and lower mortality rates. In grower-finisher barns, animals may present with anorexia, lethargy, and less severe diarrhea, but death is uncommon. This disease has a major economic impact due to high neonatal mortality, reduced nursery and finishing performance, and increased labour and treatment costs contributing to financial losses. The clinical signs associated with PDCoV infection are indistinguishable from those of PEDV, but illness and impact tend to be less severe overall.
Movement of infected pigs and transport contamination appear to have been the main causes of disease spread, and this highlights the importance of continued vigilance and strong farm biosecurity, including adequate decontamination of all vehicles (transport trailers, feed delivery trucks, etc). For more information regarding ongoing PEDV and PDCoV tracking in Ontario, visit the Swine Health Ontario website: https://www.swinehealthontario.ca/Disease-Information/PED-PDCoV-Tracking-Map [1].
References
1. Saif LJ, Wang Q, Vlasova AN, Jung K, Xiao S. Coronaviruses. In: Diseases of Swine, 12th ed. Zimmerman JJ, Karriker LA, Ramirez A, Schwartz KJ, Stevenson GW, Zhang J, eds. Wiley-Black Sons; 2026. p 564-574.
2. Swine Health Ontario. https://www.swinehealthontario.ca [2] Accessed May 13, 2026.