Diagnosis of PEDV in Colombia Swine Farms

Porcine Epidemic Diarrhea Virus (PEDV), a member of the family Coronaviridae genus Alphacoronavirus is an enveloped, single – stranded RNA virus. PED was first reported in Europe in 1978. Since then outbreaks of PED infections have been reported in many countries including Europe and Asia. In America, the PEDV was first identified in USA in May 2013.The purpose of this study was to report the detection of PEDV in natural outbreaks in Colombian Swine Farms.

Samples from 186 pig farms in Colombia from March 2014 through December 2015 were submitted to the National Veterinary Laboratory of ICA. All of the pig farms had similar disease histories, clinical signs, and lesions, including the presence of a sudden outbreak and rapid spread between farms, high mortality in neonatal piglets. Affected piglets displayed anorexia, vomit, diarrhea, and dehydration. Clinical specimens were collected and tested for porcine epidemic diarrhea virus including feces and tissues. Samples were tested by real time reverse transcriptase PCR (rRTPCR) as described for the nucleoprotein (N) gene. Formalin fixed intestinal tissues were also examined by histopathology and the PEDV antigen was detected by immunohistochemistry using a monoclonal antibody specific for the nucleoprotein as described. Samples from 10 cases were sent to NVSL USDA to reconfirm our diagnosis and also to conduct preliminary sequencing.

A total of 149 pig farms were confirmed as positive for PEDV by qPCR. Microscopic intestinal lesions consistent with viral enteritis were observed in all cases examined. The PEDV antigen was found in the cytoplasm of villous enterocytes in acute cases studied. Ten PEDV strains sequenced in NVSL were found 99 to 100% identical to the NPL-PEDV USA isolates detected in 2013 and 2014.

Our data demonstrated that PEDV is now endemic in Colombia. So far the virus has been detected in 10 departments of the main pig production regions.PEDV isolates are genetically similar to US isolates. These strains were responsible for the recent PEDV outbreak in our country and they produced a similar mortality and pathological findings as reported for the US isolates. The source of this emergent PEDV in Colombia is still unknown.

Disclosure of Interest: None Declared.