Feline Parvovirus Enteritis is also known as Feline Panleukopenia, Feline Infectious Enteritis or cat plague. Cats that have feline panleukopenia, a parvoviral infectious disease, often exhibit depression, anorexia, high temperature, vomiting, diarrhoea, and severe dehydration as a result. Much less frequently, adult cats are affected.
What causes Feline Panleukopaenia?
Feline parvovirus (FPV; also known as feline panleukopenia virus) and the type 2 canine parvoviruses (CPV) that cause canine parvoviral enteritis are closely related. All felids and some members of allied groups (such as raccoons and minks) are susceptible to disease caused by FPV, although canids are not harmed by it. On the other hand, it has been demonstrated that specific CPV strains now in circulation (CPV-2a, -2b, and -2c) can induce feline panleukopenia in domestic cats and larger felids. However, globally, feline panleukopenia is primarily caused by FPV rather than CPV. Although vaccines containing FPV induce significantly lower antibody titers against CPV-2c than against FPV, they nonetheless protect cats from CPV-related illness.
How is Feline Panleukopenia transmitted?
During the acute period of the illness, virus particles are common in all fluids and excretions. They can also persist for up to 6 weeks following recovery in the faeces of survivors. Parvoviruses are highly resistant to inactivation and can travel great distances using fomites (eg, shoes, clothing). However, FPV can be destroyed by being exposed to household bleach diluted at 1:32 (6% aqueous sodium hypochlorite) for at least 10 minutes at room temperature. Also very effective are peroxygen disinfectants, such as potassium peroxymonosulfate. Prior to applying disinfectants, it is crucial to thoroughly clean contaminated surfaces of organic material.
By coming into contact with diseased animals, their excrement, secretions, or contaminated fomites, cats can become infected orally or nasally. The first year of a cat's life is regarded to be when they are most likely to be exposed to the virus. Those who survive an acute sickness or develop subclinical infections mount a powerful, persistent, and protective immune response.
How does Feline Panleukopaenia infect a cat?
In the bone marrow, lymphoid organs, intestinal epithelium, and—in very young animals—the cerebellum and retina, FPV infects and kills actively proliferating cells. The virus can spread transplacentally in pregnant queens and result in embryonic resorption, fetal mummification, miscarriage, or stillbirth. Alternately, infection of kittens during the perinatal period may cause the destruction of the cerebellum's germinal epithelium, resulting in cerebellar hypoplasia, tremor, and incoordination. Because most queens passively transfer enough antibodies to their kittens to protect them during the early phase of vulnerability, FPV-induced cerebellar ataxia has become a rather uncommon diagnosis.
What are the clinical signs of Feline Panleukopenia?
The high seroprevalence of anti-FPV antibodies in unvaccinated, healthy cats indicates that the majority of feline panleukopenia infections are subclinical. Cats that do get sick are often under a year old. Severe cases can die suddenly often without much or any warning (fading kittens). After a 2- to the 7-day incubation period, acute cases manifest as fever (104°–107°F [40°–41.7°C]), depression, and anorexia. Vomiting normally starts 1-2 days after a fever starts; it is typically bilious and unrelated to eating. In some circumstances, hypersalivation may be present together with nausea or gastrointestinal pain.
Vomiting may start a little later than diarrhoea, however, it is not always present. Hemorrhagic diarrhoea only occurs in 3%–15% of patients. Extreme dehydration quickly sets in. Even though they may not drink much, cats with the condition may sit in their water bowl for hours. In advanced stages, patients may have hypothermia, septic shock, and disseminated intravascular coagulation.
On physical examination, severe depression, dehydration, and occasionally abdominal pain are often noted. A palpable abdomen may indicate thicker intestinal loops and larger mesenteric lymph nodes, which might cause instantaneous vomiting. Ataxia and tremors are common in cerebellar hypoplasia patients, along with normal mental function. If present, retinal lesions show up as distinct grey foci. This self-limiting sickness rarely lasts longer than 5-7 days. Among kittens under 5 months old, mortality is highest.
How is Feline Panleukopaenia diagnosed?
Cats with insufficient vaccinations typically have a presumptive diagnosis of feline panleukopenia based on clinical symptoms and the presence of leukopenia (nadir 50–3,000 WBC/mcL on a Complete Blood Count (CBC)). An immunochromatographic test kit designed to identify faecal CPV antigen can occasionally be used to confirm the diagnosis, and its specificity ranges from 94% to 100%.
Other causes of deep depression, leukopenia, and gastrointestinal symptoms are among the differential diagnoses. Considerations should be given to salmonellosis, feline leukaemia virus (FeLV), and feline immunodeficiency virus infections. Feline panleukopenia can develop in adult cats who have both FeLV and FPV infections concurrently. More severe illness is brought on by FPV infections in combination with different salmonellae or feline calicivirus than by FPV alone.
How is Feline Panleukopaenia/Parvovirus Enteritis treated?
An aggressive fluid therapy regimen, including intravenous fluid replacement and maintenance with a balanced isotonic crystalloid solution, such as lactated Ringer's solution with calculated potassium supplementation, is necessary for the successful management of acute instances of feline panleukopenia. Electrolyte abnormalities (such as hypokalemia), hypoglycemia, hypoproteinemia, anaemia, and opportunistic secondary infections frequently manifest in seriously ill cats, making supportive nursing care in the isolation unit crucial. Results can be improved by envisioning these possibilities, closely monitoring the patient, and acting quickly.
If hypoglycemia is detected, the infusion should also contain 5% glucose and B vitamins. Fresh-frozen plasma transfusion, in addition to crystalloid infusion, aids in maintaining plasma oncotic pressure and gives clotting factors to critically ill, hypoproteinemic kittens. Additionally, it offers a few anti-FPV antibodies. For the occasional cat who is very anaemic, a whole blood transfusion is preferred.
Parenteral broad-spectrum antibiotic therapy is recommended; however, aminoglycosides and other nephrotoxic medications must be avoided until the real cause of the dehydration has been adequately addressed. The most significant bacteria that cause feline panleukopenia are anaerobes and gram-negative aerobes, and there are single antibiotic drugs, albeit more expensive ones, that are effective against them. These medicines include third-generation cephalosporins (eg, ceftiofur, cefotaxime).
Worms in the intestine frequently make feline panleukopenia worse, particularly in places like shelters. The most common types of worms in cats are roundworms, hookworms, tapeworms, and whipworms. Less common feline worms that can have serious health consequences and even be fatal include heartworms, lungworms, stomach worms, bladderworms, liver flukes, and bladderworms.
For this reason, using anthelmintics (such as fenbendazole, 50 mg/kg, PO, once daily for 5 days) is crucial and can be started once vomiting has been controlled. In most cases, antiemetic (anti-vomit) medication offers some relief and enables faster enteral feeding of soft, easily digestible food. Even in the face of mild, sporadic, or persistent vomiting, feeding (little and often) should begin as soon as possible. Feeding encourages gastrointestinal mucosa healing and the restoration of a strong mucosal barrier. In order to get the vomiting under better control, cats with acute vomiting should not be fed. Only the most severely affected cases should have parenteral nourishment, and its usage shouldn't prevent aggressive attempts from starting enteral nutrition.
How is Feline Parvovirus/Panleukopaenia prevented?
For the prevention of feline panleukopenia, excellent inactivated and modified-live virus vaccinations are available that offer strong, enduring immunity. Live immunizations shouldn't be administered to sick, immunosuppressed, or pregnant cats, or to kittens younger than four weeks old. It is advised that kittens receive two or three doses of modified-live vaccine subcutaneously, spaced three to four weeks apart. At 6 to 9 weeks of age, the first immunization is often administered. To give maternal antibodies time to decline so they do not inactivate the modified-live vaccine virus, the final dose of the initial vaccination series should be given before when the kitten is 16 weeks old.
A new recommendation calls for a booster shot to be administered between 26 and 52 weeks after the initial dose since some kittens still have interfering antibodies even at 16 weeks old, which can hinder an effective immunization. After the first round of vaccinations has been finished, exposure to the virus should be avoided for 1 week. The vaccines should be boosted annually.
What is the prognosis of Feline Panleukopaenia?
Feline panleukopenia has a noticeably worse prognosis than CPV enteritis. Survival rates of 20%–51% have been reported in cats that received supportive treatment in-hospital for feline panleukopenia. Cats with hypothermia, lethargy and low body weight at the time of admission fare worse. References