Porcine respiratory coronavirus (PRCV)

Test code: S0214 - Ultrasensitive detection of porcine respiratory coronavirus by reverse transcription coupled real time PCR

Porcine respiratory coronavirus (PRCV) is a deletion mutant of transmissible gastroenteritis virus (TGEV). The deletion occurs in the spike (S) gene of TGEV. PRCV is classified as a group 1 coronavirus.

Infection of neonatal piglets with this virus can result in acute epidemic diarrhea. Although most PRCV infections of pigs are mild or subclinical, concurrent or secondary infections may cause severe symptoms. PRCV infection of young pigs is associated with transient viremia, often with extremely high titers of PRCV in the lungs. However, the various strains of PRCV have different affinities for respiratory system tissue. In many cases, the damage does not result in clinical disease and the most virulent strains generally only result in mild clinical disease.

Diagnosis of PRCV-infection is not easy because many viruses can cause similar respiratory symptoms in swine, such as swine influenza virus (SIV), porcine reproductive and respiratory syndrome virus (PRRSV), pseudorabies virus (PRV), porcine cytomegalovirus (PCMV), porcine paramyxovirus (PPMV), hemagglutinating encephalomyelitis virus (HEV), encephalomyocarditis virus (EMC), porcine parvovirus (PPV), porcine adenovirus, and porcine enterovirus.

Culture detection of PRCV is not suitable because the virus does not grow well in culture. Serological detection is also not suitable because a significant percentage of pigs may have prior exposure to the virus and confirmation of infection requires measurement of paired titers several weeks apart. Molecular detection by polymerase chain reaction is rapid, sensitive and specific, and is a good alternative to the traditional methods (Usami et al., 2008).

Utilities:

• Help confirm the disease causing agent
• Identify PRCV carriers
• Help ensure that herds are free of PRCV
• Early prevention of spread of the virus among animals
• Minimize human exposure to the virus
• Safety monitoring of biological products that derive from animals

References:
Usami, Y., Fukai, K., Ichikawa, Y., Okuda, Y., Shibata, I., Motoyama, C., Imai, K. and Kirisawa, R. (2008) Virological and serological studies of porcine respiratory coronavirus infection on a Japanese farm. J. Vet. Med. Sci. 70:929-936.

Specimen requirements: 0.2 ml whole blood in EDTA (purple top) tube, or nasal swab, or 0.2 ml feces, or rectal swab, or 0.2 ml fresh or frozen tissue.

Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology: Qualitative reverse transcription coupled real time PCR

Normal range: Nondetected