Canine Parvovirus
By Dr’s Mac Williams, Moore and Romberg
Canine Parvovirus (CPV) infection appeared suddenly in the United States of America i8n august 1978 and within one year had become widespread throughout the world. The devastating effects and worldwide spread of CPV infection have been the subject of grave concern for pet owners, dog breeder and Veterinarians alike and have motivated an intense research effort to investigate all aspects of the disease.
The disease is caused by one of the smallest known viruses which is closely related the virus responsible for infectious feline panleukopaenia (‘cat flu’ or ‘cat distemper’).
The signs of CPV infection usually include fever, depression, and loss of appetite which are followed by extremely profuse diarrhoea, often accompanied by vomiting. The stool is liquid, may contain blood and has a foul odour. Because the white blood cell count may be lower than normal, the patients resistance is reduced, which exposes it to other infections.
Another form of CPV infection may occur in puppies younger than twelve weeks of age. This form of the disease causes an inflammation of the heart muscle (myocarditis) and usually results in sudden death. The affected puppies may breathe with difficulty, cry intermittently and may develop diarrhoea.
Some dogs show no outward signs of the disease or may develop very mild symptoms. All infected dogs shed a great deal of virus in their stools which spreads the disease to susceptible dogs.
When puppies begin to nurse they may receive temporary protection against a number of diseases, including CPV. If the mother has been successfully vaccinated against CPV or has recovered from an earlier CPV infection, she will have produced protective CPV antibodies. These antibodies are passed to the puppies in their first milk. Because the amount of maternal antibodies received in this manner may vary widely, the puppies may be protected against CPV infection for a period of several weeks to several months.
The rapid spread of CPV infection and the widespread use of CPV vaccines has ensured that an increasing number of bitches are immune to the disease and thus their puppies receive maternal antibodies against CPV which are protective against the highly fatal myocarditis form of the disease.
However, the maternal antibodies, which are protective to the puppies, may interfere with the effectiveness of a vaccine. The antibodies neutralize the vaccine virus as though it were the natural CPV virus, thus preventing successful immunization. Therefore, it is important to vaccinate as soon as a puppy becomes susceptible to CPV infection, but late enough to avoid interference by the maternal antibodies.
Since puppies receive varying amounts of maternal antibodies, it is clinically impossible to determine the optimum time for vaccination. Thus for the best protection, several doses of vaccine may be required with the last dose of the vaccine given after the puppy is five months of age.
Treatment of CPV disease requires careful veterinary supervision and may be both time consuming and costly. Therapy often includes intravenous feeding, medication to control the diarrhoea and vomiting, administration of antibiotics and blood transfusions. Treatment is limited to controlling the symptoms of the disease and does not kill the virus. Since infection ranges from mild to severe even within an affected litter, the success of treatment varies too, despite intensive nursing.
Because CPV is extremely resistant the disease is easily spread and is difficult to control. Thus it is important to isolate infected dogs although even an apparently healthy dog may be spreading the virus because of a mild or inapparent infection. Contaminated areas should be disinfected using one part of hypochloride (bleach) diluted in thirty parts water or commercial chlorine disinfectants available from your veterinarian.
When CPV first appeared no specific vaccine was available to control the spread of the disease. As a result, CPV infection rapidly assumed epidemic proportions throughout the world. Because the canine parvovirus is very similar to the feline panleukopaenia virus (FPV) veterinarians first relied on FPV (‘cat flu’) vaccines as a form of protection, which was not entirely satisfactory. Subsequently, specific vaccines against CPV have been manufactured which afford superior protection although vaccine failures may occasionally occur.
It is now recommended that your puppy be vaccinated as soon as it becomes susceptible to CPV infection and that at least one booster vaccination is given after twenty weeks of age. Ideally, your puppy should receive the first CPV vaccine between 6 and 10 weeks of age, and a booster vaccine should be administered monthly until 5 months of age. Pregnant bitches should receive a booster killed virus vaccine two weeks prior to whelping to provide maximal protection to puppies. It is advisable only to purchase puppies that have proof of vaccination, and from a mother who has been vaccinated.
Dogs that survive a natural infection of CPV usually develop sufficient immunity to protect themselves against reinfection for several years. However, because there are many cases of diarrhoea and vomiting, even dogs having suspected CPV should be protected by vaccination when in good health.
By Dr’s Mac Williams, Moore and Romberg
Canine Parvovirus (CPV) infection appeared suddenly in the United States of America i8n august 1978 and within one year had become widespread throughout the world. The devastating effects and worldwide spread of CPV infection have been the subject of grave concern for pet owners, dog breeder and Veterinarians alike and have motivated an intense research effort to investigate all aspects of the disease.
The disease is caused by one of the smallest known viruses which is closely related the virus responsible for infectious feline panleukopaenia (‘cat flu’ or ‘cat distemper’).
The signs of CPV infection usually include fever, depression, and loss of appetite which are followed by extremely profuse diarrhoea, often accompanied by vomiting. The stool is liquid, may contain blood and has a foul odour. Because the white blood cell count may be lower than normal, the patients resistance is reduced, which exposes it to other infections.
Another form of CPV infection may occur in puppies younger than twelve weeks of age. This form of the disease causes an inflammation of the heart muscle (myocarditis) and usually results in sudden death. The affected puppies may breathe with difficulty, cry intermittently and may develop diarrhoea.
Some dogs show no outward signs of the disease or may develop very mild symptoms. All infected dogs shed a great deal of virus in their stools which spreads the disease to susceptible dogs.
When puppies begin to nurse they may receive temporary protection against a number of diseases, including CPV. If the mother has been successfully vaccinated against CPV or has recovered from an earlier CPV infection, she will have produced protective CPV antibodies. These antibodies are passed to the puppies in their first milk. Because the amount of maternal antibodies received in this manner may vary widely, the puppies may be protected against CPV infection for a period of several weeks to several months.
The rapid spread of CPV infection and the widespread use of CPV vaccines has ensured that an increasing number of bitches are immune to the disease and thus their puppies receive maternal antibodies against CPV which are protective against the highly fatal myocarditis form of the disease.
However, the maternal antibodies, which are protective to the puppies, may interfere with the effectiveness of a vaccine. The antibodies neutralize the vaccine virus as though it were the natural CPV virus, thus preventing successful immunization. Therefore, it is important to vaccinate as soon as a puppy becomes susceptible to CPV infection, but late enough to avoid interference by the maternal antibodies.
Since puppies receive varying amounts of maternal antibodies, it is clinically impossible to determine the optimum time for vaccination. Thus for the best protection, several doses of vaccine may be required with the last dose of the vaccine given after the puppy is five months of age.
Treatment of CPV disease requires careful veterinary supervision and may be both time consuming and costly. Therapy often includes intravenous feeding, medication to control the diarrhoea and vomiting, administration of antibiotics and blood transfusions. Treatment is limited to controlling the symptoms of the disease and does not kill the virus. Since infection ranges from mild to severe even within an affected litter, the success of treatment varies too, despite intensive nursing.
Because CPV is extremely resistant the disease is easily spread and is difficult to control. Thus it is important to isolate infected dogs although even an apparently healthy dog may be spreading the virus because of a mild or inapparent infection. Contaminated areas should be disinfected using one part of hypochloride (bleach) diluted in thirty parts water or commercial chlorine disinfectants available from your veterinarian.
When CPV first appeared no specific vaccine was available to control the spread of the disease. As a result, CPV infection rapidly assumed epidemic proportions throughout the world. Because the canine parvovirus is very similar to the feline panleukopaenia virus (FPV) veterinarians first relied on FPV (‘cat flu’) vaccines as a form of protection, which was not entirely satisfactory. Subsequently, specific vaccines against CPV have been manufactured which afford superior protection although vaccine failures may occasionally occur.
It is now recommended that your puppy be vaccinated as soon as it becomes susceptible to CPV infection and that at least one booster vaccination is given after twenty weeks of age. Ideally, your puppy should receive the first CPV vaccine between 6 and 10 weeks of age, and a booster vaccine should be administered monthly until 5 months of age. Pregnant bitches should receive a booster killed virus vaccine two weeks prior to whelping to provide maximal protection to puppies. It is advisable only to purchase puppies that have proof of vaccination, and from a mother who has been vaccinated.
Dogs that survive a natural infection of CPV usually develop sufficient immunity to protect themselves against reinfection for several years. However, because there are many cases of diarrhoea and vomiting, even dogs having suspected CPV should be protected by vaccination when in good health.
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