Parvoviruses and Coronaviruses (Dogs/Cats)
Parvoviruses are the smallest non-enveloped DNA viruses. Their capsid has an approximate diameter of 18 to 22 nm. They are highly resistant to environmental factors, can survive for several months in the external environment, can be transmitted indirectly via shoes and clothing, and can therefore also infect animals kept exclusively indoors. Canine parvovirus (CPV) evolved from feline parvovirus (FPV) in the mid-1970s. FPV and CPV are very similar and share 99% DNA sequence identity. The differences lie in a few nucleotide sequences in the structural protein, which are responsible for their differing biological properties. Today, the predominant virus types are CPV-2a, CPV-2b, and CPV-2c. They have expanded their host range and can infect both dogs and cats, cause disease, and be transmitted between them.
Coronaviruses are enveloped RNA viruses. They are not highly species-specific. For example, the canine coronavirus (CCV) is closely related to the feline coronavirus (FCoV) and is also infectious to cats. CCV can cause enteritis in cats but does not cause Feline Infectious Peritonitis (FIP). However, recent studies have shown that some isolates of the FIP virus are recombinants of the canine coronavirus and the feline coronavirus. Coronaviruses do not remain stable in the environment for long. However, when dried on surfaces—such as dog and cat food bowls and litter boxes in the home—FCoV can remain infectious for up to 7 weeks and can thus be transmitted indirectly.
Infections with parvoviruses and/or coronaviruses are common diseases in dogs and cats. In addition to the sometimes very severe course of the infection, which can even be fatal, it is essential to note that these viruses are highly contagious.
Early testing should therefore be performed at the first sign of suspicion. The canine coronavirus (CCV) is widespread in dog populations and can cause, among other things, intestinal inflammation in dogs. Its significance as a pathogen is relatively low, and it very rarely leads to death. In contrast, canine parvovirus (CPV) is a highly contagious, globally widespread pathogen that poses a major—and sometimes fatal—threat, particularly to unvaccinated dogs.
The pathogens that cause parvovirus are highly resistant to environmental factors and can survive for several months in the external environment. Feline coronavirus (FCoV) is a significant virus in cats and is very similar to the pathogen that causes feline infectious peritonitis (FIP). Feline parvovirus (FPV) is, among other things, the causative agent of panleukopenia, a frequently fatal feline disease.
Pathogen Detection: Since the clinical symptoms of mild coronavirus and parvovirus infections in dogs are very similar, and since severe cases of diarrhea may raise suspicion of a co-infection with coronaviruses and parvoviruses, the combined Fassisi® ParCo test can aid in establishing a diagnosis.
Why can and should coronaviruses and parvoviruses be tested for simultaneously, and why is a combined test for dogs and cats useful?
Since both the canine coronavirus (CCV) and the feline coronavirus (FCoV), as well as canine parvovirus (CPV) and feline parvovirus (FPV), share 99% of their DNA sequence, simultaneous detection using the Fassisi® ParCo test for dogs and cats in a single cassette is possible. The differences lie in a few nucleotide sequences, which are responsible for the different biological properties.
Canine parvovirus (CPV) evolved from feline parvovirus (FPV) in the mid-1970s. The now predominant “new” parvovirus types (CPV-2a, CPV-2b, and CPV-2c) have a broader host range. They can infect both dogs and cats, cause disease, and be transmitted between them. These have replaced the old virus type worldwide. According to current estimates, approximately 10% of clinically ill cats in Germany are infected with CPV-2a or CPV-2b and thus also pose a potential infection risk to dogs. Similarly, a dog infected with parvovirus is a source of infection for an unprotected cat. Detection of the pathogen in the feces of dogs and cats is possible as early as 2–4 days post-infection and declines again 7 days post-infection.
Use in Dogs:
Fecal examination is useful for distinguishing a CPV/CCV infection in dogs from other causes of diarrhea.
The clinical signs of mild coronavirus and parvovirus infections in dogs are often similar. A concurrent infection with both pathogens can lead to very severe disease progression. For treatment decisions and prognosis, the Fassisi® ParCo combined rapid test provides another potential quick and cost-effective diagnostic tool.
Dogs: A Potential Source of Infection for Cats?!
Canine coronavirus (CCV) is closely related to feline coronavirus (FCoV) and is also infectious to cats. CCV can cause enteritis in cats. Canine coronaviruses may play a role in the development of FIP, as recent studies have shown that some isolates of the feline infectious peritonitis virus are recombinants derived from the canine coronavirus and the feline coronavirus. However, its epidemiological significance as a pathogen in cats has not yet been clearly established. Canine coronavirus (CCV) alone does not cause FIP!
Use in cats:
Fecal testing is useful for distinguishing an FPV/FCoV infection in cats from other causes of diarrhea, so that targeted therapeutic and hygiene measures can be initiated as quickly as possible.
The Fassisi ParCo test is used to detect coronaviruses, not FIP! A positive coronavirus antigen test indicates the presence of coronaviruses. However, only 1–5% of cats with a feline coronavirus infection subsequently develop FIP; nevertheless, a positive test result should be documented and taken into account—both prognostically and therapeutically—at a later date if symptoms suggestive of FIP appear.
Canine parvovirus (CPV) and feline parvovirus (FPV) are non-enveloped, single-stranded DNA viruses and are closely related; CPV is derived from a parvovirus of the feline panleukopenia complex. Both viruses replicate in actively dividing cells; in cases of intestinal infection, this occurs in the crypt epithelium of the small intestine; FPV additionally damages bone marrow and lymphoid tissue and, in very young animals, the cerebellum and retina. Canine and feline coronaviruses (CCV/FCoV), by contrast, are enveloped RNA viruses with a tropism for the intestinal epithelium.
Transmission occurs via the fecal-oral route; parvoviruses are extremely environmentally stable and remain infectious for months to years, making contaminated surfaces and objects a major source of infection. Coronaviruses are less environmentally stable; however, the feline coronavirus is highly prevalent in multi-cat households. Clinically, canine parvovirus primarily affects unvaccinated puppies and young dogs; feline panleukopenia is particularly severe in kittens, although diarrhea is not a mandatory symptom and is usually not bloody.
Diagnostically, the detection of antigens in feces is the primary method, as infectious causes of diarrhea cannot be definitively distinguished clinically. In the case of feline coronavirus, a positive antibody titer merely indicates exposure to the pathogen; it does not correlate with the risk of developing feline infectious peritonitis (FIP) and is not diagnostic for FIP.
The Fassisi® ParCo, Parvo, and Corona, as well as the combination tests Triple, ParCo MPX, and Triple MPX, detect parvovirus and/or coronavirus antigens in the feces of dogs and cats (Triple and Triple MPX also detect Giardia duodenalis) and aid in differentiating these from other causes of diarrhea as well as in hygiene management.
References are listed on the References page.
