Parvovirus
As parvovirus a highly contagious and acute infectious disease of will dogs referred to by the canine parvovirus is caused. According to its clinical course, it is also known as canine panleukopenia and is closely related to cat disease and the infectious panleukopenia of the marten- like in terms of its cause and the symptoms it causes . In humans, the much less dangerous Parvovirus B19 can cause illness.
Puppies 2 to 16 weeks of age and old dogs are most susceptible to the disease.
Pathogen
The cause of the disease is the canine parvovirus (CPV-2), which was first described in 1977 and has since occurred in various subtypes (CPV2a-c).
The virus replicates in the cell nucleus of the affected cell and requires functions that are only available during cell division. The pathogen is very insensitive to environmental influences. At room temperature it remains infectious for more than a year, most common disinfectants are unable to inactivate it . Substances effective against the virus include sodium hypochlorite , formaldehyde and glutaraldehyde .
Pathogenesis
The pathogen enters the body through the mucous membrane of the nose and mouth. The incubation period is 2 to 10 days. Since the virus needs cells with a high rate of division in order to multiply, it particularly affects the constantly regenerating cells of the intestinal epithelium , the bone marrow and the lymphatic system . The heart muscle can also be affected, and embryo damage has also been described. The disease mainly affects young animals whose immune systems are not yet sufficiently developed. Excretion occurs mainly through the feces, possibly also through saliva and vomit. Due to its high resistance, the pathogen remains infectious for a long time and is ingested by a new host by sniffing or licking contaminated surfaces . People who have come into contact with the sick animal (dog owners, dealers, veterinarians, virus material carried over via shoes) can also be used as carriers. Although dogs of all ages are susceptible to the disease, the most severe disease courses are seen in puppies .
Symptoms
The disease announces itself with the appearance of fever (39.5–41.5 ° C), reduced feed consumption and indifference. According to the affected organ systems, symptoms of the gastrointestinal tract and the immune system predominate about 6–12 hours after the first signs. In addition to the occurrence of severe, often bloody diarrhea , there is a sharp decrease in white blood cells ( leukopenia ) and thus a reduction in the immune system of the diseased organism, which is therefore particularly susceptible to secondary bacterial infections.
In addition to these symptoms, the affected animals show the symptoms already appearing at the beginning, fatigue , reluctance to eat , dehydration and fever throughout the course of the disease . Large amounts of highly infectious pathogen material are excreted with the faeces. In severe forms, death occurs within 24 to 48 hours. Dogs three to twelve weeks old often die of the infection without first developing clinical symptoms. Here, as a result of the infestation of the heart muscle, there is an acute failure of the cardiovascular function.
Differential diagnosis
In terms of differential diagnosis , infections with the distemper virus, rota and coronaviruses and Escherichia coli infections come into consideration. In acute deaths of puppies next to bacterial is septicemia which infectious canine hepatitis a possible differential diagnosis. In the case of bloody diarrhea, acute hemorrhagic diarrhea syndrome , hookworm infestation or a foreign body in the intestine must also be considered.
treatment
An essential diagnostic and prognostic criterion is the number of leukocytes, which, with typical progression, drop to values around 500 to 3000 per microliter ( leukopenia ). The lower this value, the worse the prognosis. The viruses can be normally by means of a practical rapid test ( antigen - ELISA ) detected from the feces. A pathogen detection is also possible via cell cultures or via PCR . An indirect method is the detection of antibodies from the blood of non-vaccinated dogs.
Treatment of sick animals is initially aimed at stabilizing the patient. Infusions are necessary for this. In order to avoid bacterial infections, it is necessary to administer antibiotics . The virus itself is fought through the application of interferons and serum antibodies. Another essential aspect of the disease is compliance with strict hygiene measures to prevent the pathogen from spreading.
prophylaxis
Vaccination can help prevent infection with parvovirus . Therefore, dogs should be protected with a primary vaccination followed by a booster vaccination. Because puppies often have protection from maternal antibodies for a very long time, the right time to start a primary vaccination may vary. The Standing Vaccination Commission recommends a first vaccination for young dogs at the age of eight weeks, a second vaccination four weeks later and the third vaccination at 16 weeks as well as a booster after 15 months. From the age of two, a refresher every three years is sufficient. If a puppy is only vaccinated for the first time after twelve weeks of life, two vaccinations every three to four weeks and a booster after another year for basic immunization are sufficient. Vaccines are also available that allow dogs to be vaccinated as early as six weeks of age.
Individual evidence
- ↑ Standing Vet. Vaccination Commission in the Federal Association of Practicing Veterinarians: Guideline for the vaccination of small animals. (July 2013, PDF file; 502 kB)
Literature and Sources
Katrin Hartmann and Peter F. Suter: Virus infections . In: Peter F. Suter and Hans G. Nobody (eds.): Internship at the dog clinic . Paul-Parey-Verlag, 10th edition 2006, pp. 276-290, ISBN 3-8304-4141-X
