Learn More About a Disease

Porcine epidemic diarrhea (PED)

Porcine Epidemic Diarrhea Virus (PEDV) is caused by a coronavirus; it affects pigs of any age and, in terms of clinical signs, resembles Transmissible Gastroenteritis (TGE) in many ways. This condition appeared in Europe thirty years ago but did not persist. A variant appeared in Asia after the year 2000, and it is this strain that was identified in the United States in the spring of 2013, then in Canada in early 2014.

Clinical Signs +

Diarrhea is the only symptom directly related to the virus. The sudden appearance in a vulnerable herd is like Transmissible Gastroenteritis (TGE) and is characterized by watery diarrhea in pigs of any age. Contrary to TGE, the incubation period is longer (3 to 4 days). Older pigs are more lethargic and worn out. Sick pigs appear to have colic. It is also possible that no visible signs appear in older pigs.

Transmission +

The virus is mainly transmitted through infected pigs and contaminated intermediary objects (boots, transport trucks etc.). The number of viral particles produced is several times greater than for TGE. Particle transmission is thereby easily possible within a radius of several kilometers around the infected farm.

Diagnosis +

Diagnosis is made in newborns by direct immunofluorescence on frozen sections of the small intestine or colon. An ELISA test is best suited to older animals for detecting viral antibodies in feces and intestinal contents. PCR analysis with primers that differentiates between TGE coronavirus and PEDV is currently the most widely used test.

Treatment +

No specific treatment is available. Actions taken during an epidemic are general. Pigs with diarrhea must have easy access to water. Two vaccines given to sows (to transfer antibodies through colostrum and milk to piglets) are currently available in the United States and will soon be available in Canada. Protection seems incomplete. Actions such as exposing breeding stock to the live wild virus produces protection, but recontaminations are noted.

Your veterinary doctor is the best source of recommendations that are truly suited to your farm.

Prevention +

Prevention is entirely based on biosecurity measures that relate to animal transportation, truck cleaning and controlling the contamination of unloading platforms. Contaminated Canadian farms have generally opted to eliminate the virus from their farm.


1 Merck Veterinary Manual, Third Edition