Ahead of Print -Pathogenicity of 2 Porcine Deltacoronavirus Strains in Gnotobiotic Pigs - Volume 21, Number 4—April 2015 - Emerging Infectious Disease journal - CDC

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Ahead of Print -Pathogenicity of 2 Porcine Deltacoronavirus Strains in Gnotobiotic Pigs - Volume 21, Number 4—April 2015 - Emerging Infectious Disease journal - CDC

Volume 21, Number 4—April 2015

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Pathogenicity of 2 Porcine Deltacoronavirus Strains in Gnotobiotic Pigs

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• The Study
• Conclusions
• Suggested Citation

Figures

• Figure 1
• Figure 2

Tables

• Table 1
• Table 2

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Kwonil Jung , Hui Hu, Bryan Eyerly, Zhongyan Lu, Juliet Chepngeno, and Linda J. Saif 

Author affiliations: Ohio State University, Wooster, Ohio, USA

Suggested citation for this article

Abstract

To verify whether porcine deltacoronavirus infection induces disease, we inoculated gnotobiotic pigs with 2 virus strains (OH-FD22 and OH-FD100) identified by 2 specific reverse transcription PCRs. At 21–120 h postinoculation, pigs exhibited severe diarrhea, vomiting, fecal shedding of virus, and severe atrophic enteritis. These findings confirm that these 2 strains are enteropathogenic in pigs.

Porcine epidemic diarrhea virus (PEDV) (family Coronaviridae, genus Alphacoronavirus) was discovered in the United States in May 2013. The virus has now spread nationwide and caused a high number of deaths among suckling pigs (1,2). In regions of the United States to which PEDV is epidemic, a new coronavirus, genetically distinct from PEDV, porcine deltacoronavirus (PDCoV) (genus Deltacoronavirus), has been simultaneously and frequently detected in diarrheic fecal samples from pigs (3–5).

The clinical role and disease severity of PDCoV in the field is reportedly less than that of PEDV (6). To confirm the role of PDCoV as an enteric viral pathogen and understand disease progression, we studied the pathogenicity of 2 strains of PDCoV (OH-FD22 and OH-FD100) in gnotobiotic pigs. We developed in situ hybridization and immunofluorescence staining methods to verify the tissue sites of PDCoV replication in infected pigs.

Acknowledgments

We thank J. Hanson, R. Wood, and J. Ogg for assisting with animal care; Q. Wang for providing advice on qRT-PCR for PDCoV; and X. Wang and M. Lee for providing technical assistance.

Salaries and research support were provided by state and federal funds appropriated to the Ohio Agricultural Research and Development Center, Ohio State University. This study was supported by Four Star Animal Health Inc. (Loramie, OH, USA) (L.J.S.) and Ohio Agricultural Research and Development Center SEEDS Program (grant OAOH1536 to K.J.).

Dr. Jung is a veterinary pathologist at Ohio State University, Wooster, Ohio. His research interests include diagnostic molecular pathology and pathogenesis of virus infections and analysis of immune responses to swine enteric viral infections by using germ-free or conventional pig models.

References

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Figures

• Figure 1. Porcine deltacoronavirus (OH-FD22) particle detected in intestinal contents from a gnotobiotic pig. The sample was negatively stained with 3% phosphotungstic acid. Scale bar = 100 nm.
• Figure 2. Intestinal changes in gnotobiotic pigs inoculated with porcine deltacoronavirus (PDCoV) strains OH-FD22 (panels A, B, E, G, I, and J) and OH-FD100 (panels D and K). A) Intestine of...

Tables

• Table 1. Fecal shedding of virus and clinical signs after inoculation of gnotobiotic pigs with PDCoV strains OH-FD22 and OH-FD100
• Table 2. Histopathologic findings after inoculation of gnotobiotic pigs with PDCoV strains OH-FD22 and OH-FD100

Suggested citation for this article: Jung K, Hu H, Eyerly B, Lu Z, Chepngeno J, Saif LJ. Pathogenicity of 2 porcine deltacoronavirus strains in gnotobiotic pigs. Emerg Infect Dis. 2015 Apr [date cited]. http://dx.doi.org/10.3201/eid2104.141859

DOI: 10.3201/eid2104.141859