D315 - Canine adenovirus type 1

Description:

Canine coronavirus (CCV) is a cause of sporadic outbreaks of enteritis in dogs. Dogs of all ages appear to be susceptible to Canine coronavirus; however, young pups are more highly susceptible to the development of clinical infections. The natural route of transmission is fecal-oral. Virus in feces is the major source of infection. Infected dogs shed CCV in the feces for 6-9 days, but shedding can be prolonged in some pups, after clinical signs have ceased. Canine coronavirus is acid resistant and passes unaltered through the stomach. The surface epithelium of the small intestine is the main target of CCV, while the colon is resistant to the infection.
The incubation period is short. Vomiting and diarrhea may be seen by 1-3 days post infection and, when clinical illness occurs, it spreads rapidly. The virus is highly contagious and often may cause clinical signs in some dogs, with no illness occurring in contact animals. Feces may be mucoid or watery, sometimes streaked with blood, and it is exceptionally malodorous. Pups become dehydrated, even if fluid therapy is started early, depressed and anorexic. The infection is generally afebrile although elevated body temperature has been observed in some cases. In contrast to CPV-2 infection, leukopenia has not been observed. Vomiting, which is much less severe than with CPV-2 infection, usually subsides after the first day of illness, but diarrhea persists several days, even for 3-4 weeks. Secondary infections by bacteria, parasites or other viruses, such as parvoviruses or rotaviruses, may protract the illness. However, dogs usually recover spontaneously within a week, but illness may last 2 weeks or longer. The mortality rate of Canine coronavirus infection alone is usually very low, but deaths have been reported in some kennels, especially in pups.

Diagnosis:

Canine coronavirus infection is difficult to distinguish clinically from enteritis caused by other agents. It is important to rule out other causes of vomiting and diarrhea such as enteric bacteria, parasites, poisonings and non-infectious causes of diarrhea. Assays, which have been used for the detection of CCV in fecal samples, include electron microscopy (EM), isolation on appropriate cell cultures and nested-polymerase chain reaction (PCR). Of the several methods used for the detection of Canine coronavirus, EM appears to be a valuable diagnostic tool. EM has been reported to be more sensitive and useful than virus isolation for detecting coronaviruse. However, the frequency of Canine coronavirus disease has probably been overestimated by diagnostic laboratories, which applied EM as the principal diagnostic method. The common presence of coronavirus-like particles in feces presents difficulties in the diagnosis of CCV by EM and requires confirmation by other tests. Immuno-electronmicroscopy with a specific immune serum permits confirmation of the EM diagnosis, but it requires specialized laboratories and qualified experts.
Nested PCR assay for the diagnosis of Canine coronavirus infection has been developed. The target sequence for amplification is a segment of the gene encoding for transmembrane (M) protein of CCV. The test revealed high specificity and sensitivity. The PCR allows the diagnosis of Canine coronavirus more rapidly than traditional tests (EM or isolation on tissue cultures), and would be suitable for the diagnosis of CCV in fecal samples when the virus is inactivated, or when the number of virions is low and cannot be detected by EM examination.

Sample:

1. Fecal sample in a sterile container.

Special Handling:

Store sample at 4°C until pick up or shipment.

Test Code:

D3371