D3211 - Canine herpes virus

Description:

Canine herpes virus is a viral disease that affects many puppies, causing sporadic deaths and occasionally the death of an entire litter. The virus lives in the reproductive and respiratory tracts of male and female dogs and can be sexually transmitted. The virus persists in the female's vaginal secretions and the male's semen. As in many herpes infections found in other species, adult animals can live for years with no apparent signs; these are called "asymptomatic carriers". This means the adult male and female dogs can remain infected and transmit the disease for years while showing no signs of disease themselves. Puppies can become infected several ways. The virus can cross the placenta and infect them while they are still within the uterus, or they may become exposed from vaginal secretions during birth. The virus can also become airborne from nasal secretions of the mother, so once born, the pup can actually inhale the virus while breathing. Puppies can easily spread the virus from one to another. Lastly, eating infected materials can transmit the virus. Once exposed, it generally takes about a week for symptoms to appear. With this in mind, you can easily see why 1 to 3 week old puppies are at the highest risk. Severely infected individuals will become depressed, stop nursing and cry. Their feces will be soft and yellow-green. The abdominal area becomes painful and the liver becomes enlarged and damaged resulting in its dysfunction. Some puppies develop respiratory signs and nasal discharge. Others develop a rash on their abdomen. Hemorrhages such as nose bleeds and small bruises on the mucous membranes or skin may appear. Some puppies will show nervous system signs such as blindness and staggering. Puppies usually die within 24-48 hours of showing signs of disease.
Not all pups exposed at birth become ill, and many show no signs at all or develop only a slight congestion and recover within a few days. Puppies exposed after six weeks of age have a better chance of recovery. Older puppies develop the disease by coming in contact with the mother's infected, but normal-appearing, nasal secretions. Those that live often develop into carrier adults just like their parents. It appears that the virus thrives best at a temperature of around 99oF, so this may help to explain why older puppies are at less risk as their body temperature is usually around 101.5oF.Adult carriers typically exhibit no obvious symptoms, however, small blister-like lesions may occasionally be noted on the vaginal wall.

Diagnosis:

Canine herpes virus is one of the leading causes of death in newborn puppies. Once the above signs develop, death often follows in 48 hours. The disease spreads rapidly through the litter as infected puppies are highly contagious. We suspect many cases of herpes virus are wrongly diagnosed as disorders such as parvovirus and coronavirus. PCR can be used as a conformation test for detection of herper virus genetic material in blood and tissue specimens.

Sample:

1. Whole blood (3 ml) in a lavender top (EDTA) tube.
2. Tissue samples from affected organs.

Special Handling:

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

Test Code:

D3211

1. Miyoshi et al. (1999) Detection of canine herpesvirus DNA in the ganglionic neurons and the lymph node lymphocytes of latently infected dogs. J. Vet. Med. Sci. 61: 375-379.
2. Schulze et al. (1998) Nested polymerase chain reaction and in situ hybridization for diagnosis of canine herpesvirus infection in puppies. Vet. Pathol. 35:209-217.
3. Smith K.C. (1997) Herpesviral abortion in domestic animals. Vet. J. 53: 253-68.