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Specific Diseases We Vaccinate Against (about the diseases: clinical signs, transmission, susceptibility, and prevention):
Dogs and Cats
Rabies
We are all familiar with the classic picture of the frothing, angry rabid dog.
- Clinical signs: Symptoms are extremely varied, but primarily affect the central nervous system and behavior of the animal. Vague signs such as anxiety, fever, and attitude changes mark the initial findings. In large animals, colic or choke can occur. These signs often progress in animals to the “furious” form (hyperexcitability and hyperactivity) or the “dumb” form (paralysis). After the onset of symptoms, death usually occurs within 10 days. In humans and animals, once clinical signs become apparent, the disease is 90-100% fatal.
- Who is susceptible: All warm-blooded animals are susceptible to the virus. Domestic animals that seem to be the most susceptible are dogs, cats, cattle and horses. Rabies can occur but is more rarely seen in sheep, goats and swine. In wild animals, it is seen the most in raccoons, skunks, bats and foxes. There is some evidence that bats may be non-symptomatic carriers of the virus. Worldwide, there are about 50,000-100,000 human deaths per year to rabies.
- Transmission: The saliva of rabid animals contains a large amount of virus, thus almost all cases originate from bite wounds. A few cases have been reported to have occurred from contamination of wounds or mucous membranes. Once the virus enters the system, it replicates in the muscle cells. It then enters peripheral nerves, travels to the brain, and then spreads to the rest of the body. It is primarily shed in saliva and urine.
- Prevention: Rabies vaccines are a very effective means of prevention; and rabies in domesticated animals has been nearly eradicated in some areas through vaccine use. The virus is fairly fragile in the environment. It is easily inactivated by drying or the use of disinfectants. Even regular hand soap can be an effective disinfectant against rabies virus, so any time you are bitten, irrigate and wash the wound thoroughly with soap and water, and contact your physician.
- Treatment: If a human is exposed, a “post-exposure” vaccine can be effective, provided the virus has not yet infected the central nervous system. Because of the severity of the disease and potential for transmission, domestic animals that are infected are not treated, but are euthanized.
Dogs: Diseases Prevented by our Core Vaccines
Distemper
Distemper virus results in a deadly viral infection; involving GI, respiratory and nervous systems. Very few dogs survive the disease, and those that do often have residual neurologic or visual deficits.
- Clinical signs: Depending on the strain of distemper virus causing infection, clinical signs exhibited may primarily involve the central nervous system, respiratory system, or gastrointestinal system; but often progress to involve several or all three of these systems. The disease often begins with a fever, then coughing, diarrhea, vomiting, anorexia, dehydration may follow. Mucopurulent ocular and nasal discharge and pneumonia are sometimes present. Muscle stiffness, “chewing gum” seizures, incoordination, circling, vocalization, fear, and blindness are common neurologic signs.
- Who is susceptible: Canine Distemper virus can infect all members of the Canidae family (dogs, dingoes, foxes, coyotes, wolves, jackals), the Mustelidae family (ferrets, minks skunks, badgers, martens, weasels, otters) and the Procyonidae family (raccoons).
- Transmission: Distemper virus of infected animals is shed in high numbers in all body secretions, and is transmitted by inhalation or ingestion of aerosolized secretions.
- Prevention: Vaccines are a very effective means of prevention, and very few cases are seen now that vaccine use is more common. Distemper virus has a relative fragile structure, so is easily inactivated by heat, drying, detergents, solvents, and disinfectants.
Adenovirus 2 (Hepatitis Virus)
There are two types of Adenoviruses that affect dogs—Adenovirus type 1 and Adenovirus type 2. Adenovirus 1 causes infectious canine hepatitis. Adenovirus 2 causes an infection that affects the respiratory system, and can be a part of the kennel cough complex. Reactions can be seen from vaccinating against Adenovirus 1, but fortunate for us, vaccinating against Adenovirus 2 (which causes very few reactions) cross-protects against Adenovirus 1.
- Clinical signs: Adenovirus 1 infection affects primarily the liver, central nervous system and eyes; the kidney, gastrointestinal system and respiratory system can also be affected. Signs vary from mild (fever, “blue eyes” or corneal edema) to severe (encephalitis, intestinal hemorrhage, severe hepatitis, frank hemorrhage, shock and death). Adenovirus 2 primarily affects the respiratory system, causing coughing, nasal and ocular discharge.
- Who is susceptible: Adenoviruses are highly contagious viruses that affect dogs, foxes and other canids.
- Transmission: Adenovirus 1 transmission is primarily through inhalation or ingestion. The virus is shed in urine, feces, saliva and respiratory tract secretions. Adenovirus 2 has a strict affinity for the respiratory tract, so is shed primarily in respiratory secretions and is transmitted via inhalation.
- Prevention: Vaccination has made disease due to Adenovirus 1 relatively rare in domestic dogs. In spite of vaccination, Adenovirus 2 infections still occur on a limited basis, however infections are usually mild or even inapparent. Adenoviruses are relatively stable, and can last for days to months in the environment. The virus is moderately resistant to disinfectants, but is susceptible to quaternary ammonium compounds.
Parainfluenza
Parainfluenza is one of the causative agents of canine kennel cough, or infectious tracheobronchitis. Kennel cough is often caused by a plethora of viral agents, including canine adenovirus 2, canine reoviruses, canine herpesvirus, and canine parainfluenza virus. Secondary bacterial invaders, such as Bordetella and mycoplasma are often also involved.
- Clinical signs: The classical signs of kennel cough are seen in infected dogs, including fever, nasal discharge, tonsillitis, and a dry, harsh, hacking cough.
- Who is susceptible: Dogs of all ages are susceptible to infectious tracheobronchitis.
- Transmission: The virus is shed in respiratory secretions, and transmitted via inhalation of aerosolized droplets.
- Prevention: Vaccines are variably effective because of the complex nature of agents causing infectious tracheobronchitis. While vaccines often do not fully protect against disease, they often limit the clinical signs. Canine parainfluenza virus does not survive long in the environment, and is easily inactivated with commonly-used disinfectants.
Parvovirus
Parvovirus infection is known for causing severe gastroenteritis which can sometimes be fatal.
- Clinical signs: Clinical signs primarily involve the gastrointestinal tract (including severe diarrhea, vomiting and resulting dehydration), but may rarely involve the heart as well. Myocarditis (inflammation of the heart muscle) is most often seen in puppies infected at less than 8 weeks old or in puppies that were infected in utero.
- Who is susceptible: All Canidae are likely susceptible to canine parvovirus. New strains may also infect cats, although this appears to be a rare occurrence at the present time. Puppies 6 weeks to 6 months old appear to be the most susceptible, although dogs as old as 2 years of age are occasionally seen. Rottweilers, Doberman Pinschers, Labradors, Pit Bulls, German Shepherd dogs, Staffordshire Terriers, English Springer Spaniels, and Alaskan breeds seem to be at increased risk of developing the disease.
- Transmission: Transmission occurs through exposure to virally-contaminated feces. People, rodents, and contaminated objects or clothing can also serve as vectors. Infected animals may shed the virus for 12-21 days, even if signs of illness have resolved.
- Prevention: Although not 100% effective, vaccination is a valuable means of prevention. Additionally, preventing puppies’ exposure to the feces of other dogs is recommended until the puppy had been thoroughly vaccinated. Puppies that have recovered from parvovirus infection have been shown to have prolonged (20 months) or sometimes lifelong immunity. Canine Parvovirus is extremely stable in the environment and resistant to many disinfectants. It has been shown to be susceptible to bleach, however. Without proper disinfection, parvovirus has been shown to persist on clothing, bowls and on cages for more than five months.
Dogs: Diseases Prevented by our Non-core Vaccines
Bordetella
Bordetella bronchiseptica is a bacterial invader, often involved in the canine infectious tracheobronchitis (kennel cough) complex. As mention above (under Parainfluenza virus), canine kennel cough often begins with viral invaders which compromise and “tie up” the immune system in the respiratory tract. From there, secondary bacterial invaders like Bordetella take hold.
- Clinical signs: The classical signs of kennel cough seen in infected dogs include fever, nasal discharge, sneezing, tonsillitis, and a dry, harsh, hacking cough. As the disease progresses, dogs often quit eating and become listless.
- Who is susceptible: Dogs and cats of all ages are susceptible to infectious tracheobronchitis; however, younger and older animals seem more predisposed. In both species, respiratory disease from Bordetella alone is very rare. In fact, some predisposing factor almost always has to be present for an animal to be susceptible to Bordetella infection. Most of the time, the “predisposing factor” is an already-established viral infection. Can dogs and cats transmit Bordetella to each other? Only in very specific situations. Because the viral agents that infect dogs and cats are species-specific (dog respiratory viruses do not infect cats, and vice-versa), it is very rare that a dog and cat in the same household could transmit Bordetella infection to each other. In other words, the infected animal would have to contact an already respiratory-compromised companion for transmission of the bacteria to occur. As a side note, Guinea pigs are very susceptible to Bordetella infection, and it can be a primary cause of severe respiratory disease in this species (previous compromise from a viral infection is not necessary). If you have a dog or cat with any type of upper respiratory disease, it is strongly recommended that you keep these pets isolated from your Guinea pig! As another side note: rabbits are common carriers of Bordetella (they can harbor the bacterium, shed it, and never show signs). This is why it is not a good idea to keep Guinea pigs and rabbits in close proximity of each other!
- Transmission: The bacterium is shed in respiratory secretions, and transmitted via inhalation of aerosolized droplets. Carriers of Bordetella (dogs and cats) shed the bacteria when stressed (even though they may not show respiratory signs), so provide a constant source of contamination in kennel or “group housing” environments.
- Prevention: Vaccines are variably effective because of the complex nature of agents causing infectious tracheobronchitis. While vaccines often do not fully protect against disease, they often limit the clinical signs. For dogs, combination vaccines, containing both Parainfluenza virus and Bordetella bronchiseptica seem to provide the most protection. For dogs at high risk (those that board a lot or those that visit the groomer on a regular basis), your vet might recommend boostering this vaccine every 6-8 months. Cat vaccines do exist, however at this time they are reserved for use in shelters and humane societies. Bordetella can survive for a short time in the environment, but is easily inactivated with commonly-used disinfectants. When in a kennel environment, the potential for carriers and persistent re-contamination necessitates regular disinfection.
Leptospirosis
Leptospira bacteria exist in many serovars (bacterial subtypes), and may infect many species including cattle, dogs, humans and rarely cats. Immunity towards one serovar does not guarantee immunity against another serovar.
- Clinical signs: Clinical signs vary with age and immune status as well as the serovar(s) that an individual is exposed to. Although the liver and kidneys are the primary target organs, signs are often vague and include: fever, muscle soreness and stiffness, shivering, weakness, anorexia, depression, diarrhea, vomiting, icterus, cough, polyuria/polydipsia, abortion, and impaired blood coagulation (resulting in nosebleeds, blood in the urine and/or stools).
- Who is susceptible: Many species are susceptible, including large domestic animals, humans, and dogs. Cats can very rarely become infected.
- Transmission: Each serovar has its own routes of exposure, however most are transmitted through contact with infected urine or other bodily fluids (semen, vaginal discharge, infected fetal or post-abortion discharge). Indirect exposure to contaminated vegetation, soil, food, water and bedding can also transmit the disease.
- Prevention: Vaccination provides good protection, however immunity is limited in duration (usually lasts only 6-8 months) and in serovar coverage. Vaccinate at-risk dogs every 6 months, limit access to stagnant water, heavily irrigated pastures and wildlife. Strict sanitation (keep urine cleaned up) and disinfection with iodine or bleach-based solutions prevents transmission. Because of the zoonotic potential, avoid contact with urine of potentially affected animals. This disease is reportedly extremely rare in cats, and therefore vaccines for this species do not currently exist.
Canine Coronavirus
Coronaviruses exist for many mammalian species, but are fortunately very species-specific (i.e. dog coronaviruses do not infect people, and vice-versa). (See below under Feline Infectious Peritonitis for information on feline coronavirus).
- Clinical signs: Canine Coronavirus causes acute gastroenteritis. Signs include vomiting and diarrhea (often orange, watery and malodorous). Most dogs recover unless other infections are present (like parvovirus), then recovery is variable.
- Who is susceptible: All members of the Canidae family are susceptible. While all ages are susceptible, newborns up to weaning age-pups are the most severely affected. Adults usually show mild or no signs if infected.
- Transmission: Coronavirus is shed in the feces of infected dogs for 2 weeks or longer, and the virus can persist in the environment for prolonged periods (usually weeks). Transmission is through fecal-oral contact.
- Prevention: Vaccines provide incomplete protection against the virus and result in only short-term immunity (2-4 weeks). Sanitation is a more effective means of preventing spread in kennels and hospitals. Most disinfectants are effective against this virus.
Lyme Disease
Lyme disease is caused by a bacterial infection with Borrelia burgdorferi, hence the disease is also known as “borreliosis”. Transmission of the bacterium is complicated in nature, and involves intermediate hosts (ie lyme disease is not transmitted from dog to dog). In short: Young (larval stage) Ixodes ticks (a specific species of ticks) feed on mice that are persistently infected with the bacteria. The bacteria enter the tick during this feeding, and persist in the tick while the tick develops to its adult stage. Adult female ticks feed on dogs, thereby transmitting the bacteria into the dog’s bloodstream. Several “tales” exist regarding the transmission of Lyme disease from dogs to humans. In one story, bacteria in the saliva or urine of an infected dog transmitted the disease. Again, a tick is required for transmission of the Lyme bacteria; the infected dog cannot transmit the bacteria directly to a human or another dog. In another story, a tick jumped off of an infected dog and onto a person, thereby transmitting the disease. This is reportedly uncharacteristic of the Ixodid tick species, once attached, an adult tick feeds until it is “full” and then detaches; it does not change hosts midway through feeding.
- Clinical signs: A localized skin irritation (where the tick transmitted the bacterium) is often initially present. Two to five months later, signs of the disease start manifesting. Dogs with Lyme disease often show recurring, acute, “waxing and waning” bouts of arthritis, muscle soreness and lameness. These events commonly last for only 3-4 days. During these episodes they will commonly run a fever, go off food and show depression. Lymph nodes are commonly enlarged during these stages. In some cases, cardiac, neurologic, or renal problems will also manifest; infection of these organs can be severe and lead to death.
- Who is susceptible: Dogs, humans, and rarely cats can be infected with B. burgdorferi. It has also been reported in horses, cattle, and many wildlife species. Young dogs seem more susceptible than adults and older dogs. Lyme disease has been identified everywhere in the world. In the United States, greater than 90% of the cases occur in the northeastern states. The upper Mississippi region, California, and some southern states have also had cases of the disease. It is reportedly very rare in the Northwest, probably because the species of ticks that transmit the bacteria are rare in our area.
- Transmission: Infection of the dog with B. burgdorferi requires that an infected tick feeds on the dog. In order for a sufficient amount of bacteria to transmit to the dog and cause disease, the tick must remain attached for a minimum of 24 to 48 hours. Depending on the area of the country, 5-80% of dogs have a titer to the bacterium (have antibodies in their bloodstream, indicating they have been exposed to the bacterium); but only 5% of these reportedly develop the disease.
- Prevention: Products that deter ticks from attaching are the most effective (products with DEET or permethrin). Thorough grooming after your dog has been in a tick-endemic area will also help. Products that kill biting ticks before they have time to transmit the bacteria are also effective (such as Frontline). Vaccines exist but show variable efficacy. As mentioned above, only 5% of the 5 to 80% of dogs that are exposed develop the disease. In vaccine studies it has been shown that only 1% of vaccinated dogs develop the disease. We do offer the vaccine at Prairie, but reserve its use for those dogs that will be in Lyme-endemic areas (like the northeastern U.S.).
Cats: Diseases Prevented by our Core Vaccines
Feline Viral Rhinotracheitis/Rhinopneumonitis
Feline rhinotracheitis (affecting the nose and trachea) and rhinopneumonitis (affecting the nose and lungs) is caused by a feline herpesvirus. Herpesviruses are interesting viruses, which are known for their states of “latency”. This means that they can survive in the animal for its lifetime, popping up during times of stress to cause disease over and over again. They also may be shed by latently infected animals that show no signs of infection. Feline herpesvirus causes disease of the respiratory system, and is often part of the feline upper respiratory disease complex.
- Clinical signs: Feline Herpesvirus infection causes fever, sneezing, coughing, dyspnea (difficulty breathing), and conjunctivitis (“pink eye”). Occasionally, ulceration of the nasal and oral cavities can occur, resulting in hypersalivation and decreased appetite. In some cases, severe ulcerative keratitis (ulcers of the cornea) can predominate.
- Who is susceptible: Both wild and domestic cats are susceptible. Generally, the younger the kitten, the more severe the disease signs. Infected kittens younger than 6 weeks old may become hypothermic, develop severe pneumonia, and die. Kittens older that 12 weeks of age generally show mild signs. Queens infected during pregnancy may abort.
- Transmission: Transmission is by direct contact with oronasal secretions of affected cats. After infection and recovery from the disease state, cats enter a latent phase. They may shed the virus spontaneously with or without clinically apparent signs of disease. Many queens will spontaneously shed virus at parturition and during nursing.
- Prevention: Vaccines do not prevent infection, but are generally effective at limiting the clinical signs of illness. The virus does not naturally last long in the environment, and is easily destroyed by most commonly used disinfectants.
Chlamydia
Chlamydia psittaci is an intracellular bacterium that causes upper respiratory infection in cats. Humans are occasionally accidental hosts, and the bacteria in humans cause similar signs to those seen in cats. This disease should not be confused with Chlamydia trachomatis infection in humans (a sexually transmitted disease).
- Clinical signs: Chlamydia infection in cats usually causes mild rhinitis, bronchitis, and conjunctivitis. Occasional progression to pneumonia is rarely seen. Nasal discharge, sneezing, watery eyes, sensitivity to light, and coughing are common. A small proportion of cats may become chronically infected. Many cats show no signs of infection unless co-infected by other agents (Calicivirus, Herpesvirus, Bordetella, etc.).
- Who is susceptible: All domestic cats are susceptible, kittens 2-6 months old seem to be more susceptible than adults.
- Transmission: Aerosol transmission through ocular and nasal droplets is documented.
- Prevention: Vaccines do not prevent infection, but often lessen the severity and duration of signs. Chlamydia is susceptible to most common disinfectants.
Calicivirus
Calicivirus infection involves the respiratory system, and is often part of the feline upper respiratory disease complex.
- Clinical signs: Infection causes acute respiratory disease. Signs include fever, sneezing, coughing, nasal and ocular discharge. Occasionally hypersalivation from oral ulcers can be seen. Ulcers can occur on the tongue, hard palate, or even the tip of the nose. In very severe cases, pneumonia, enteritis and arthritis can be seen. Severity of signs depends on the strain of the virus, the presence of secondary infections, and the age of the cat infected.
- Who is susceptible: Calicivirus is a highly contagious virus that affects domestic cats and some wild cats, such as cheetahs.
- Transmission: Transmission is by direct contact with oronasal secretions of affected cats. The virus has also been isolated from the feces of infected cats. The virus is especially hardy in the environment, and contaminated objects are a common source of transmission (such as food and water dishes, or the hands, feet and clothing of people). After infection and recovery from the disease state, cats may develop persistent, subclinical infections with intermittent shedding of virus for months to years. Therefore, the virus is maintained in the population by persistently infected carrier cats.
- Prevention: Due to the large number of viral strains in existence, the vaccine can cross-protect against many strains but not all of them. For this reason, vaccines unfortunately do not prevent infection or shedding. They do, however, modify the severity of the disease, (i.e. vaccinated cats usually do not succumb to disease as profoundly as unvaccinated cats). Husbandry to prevent cat to cat contact, as well as proper disinfection of cages and bowls is very important. The virus is a stable one, resistant to most disinfectants, with the exception of 1:32 dilutions of bleach.
Panleukopenia
Panleukopenia gets its name from its ability to affect the bone marrow; resulting in white blood cell suppression (“panleukopenia”) and impaired immune function. This virus causes the feline form of parvovirus which is often fatal. Infected mothers often give birth to kittens with cerebellar hypoplasia (a debilitating brain defect).
- Clinical signs: Signs vary depending on the age at which an animal is exposed. Infection in pregnant queens may result in abortion or other reproductive problems. If kittens are born alive they usually have cerebellar hypoplasia and/or retinal dysplasia. Kittens infected after 3-4 weeks of age show classic “parvo”-like signs, including abdominal pain, vomiting, hemorrhagic diarrhea, dehydration and fever. Severe infections may result in death within 24 hours. Adult cats that become infected may have inapparent illness or mild gastrointestinal signs. Cats that recover often have lifelong immunity.
- Who is susceptible: Both domestic and wild cats are susceptible, as well as ferrets (and other members of the Mustelidae family) and raccoons. All ages are susceptible, but kittens are especially prone.
- Transmission: After infection, the virus is shed in high numbers from all body secretions for weeks to months. Direct contact with affected animals or fomites (infectious materials from the environment) can result in transmission. Inhalation or ingestion provides the means for infection.
- Prevention: Vaccines are very effective and disease is nearly non-existent in vaccinated pets. Unvaccinated young cats, feral cats, and wild felids are most at risk. The Panleukopenia virus, like Parvovirus, is very hardy in the environment and may remain viable for over a year. It is resistant to quaternary ammonium, iodine, and phenol disinfectants, but appears susceptible to formalin, glutaraldehyde, or 1:32 dilutions of bleach.
Leukemia
Feline leukemia virus is actually a complex grouping of retroviruses with several subgroups. Disease manifestation appears to depend on the subgroup encountered, the immunity of the cat, and the presence of other diseases. Some cats can be inapparent carriers of the virus and never show signs of disease. Others succumb to illness and may fully recover and clear the virus or become a carrier. Still others develop the disease with fatal consequences.
- Clinical signs: Clinical signs range from anemia and immunodeficiency to full-blown systemic disease and neoplasia (tumor formation). Infected queens may abort, or kittens from infected queens may be born dead. About 20% of kittens infected in utero may survive, and grow to become persistently affected adults, never showing signs of disease but intermittently shedding the virus. As mentioned, older kittens and cats that succumb to disease may show various clinical signs ranging from mild to severe. Fever, malaise, diarrhea and leukopenia are common, and occasional generalized lymphadenopathy may be seen (inflammation of all lymph nodes). Nearly any or all systems can be affected. Most cats affected in these manners survive with supportive care, but may have latent infections that recrudesce during times of stress or if other diseases are encountered. Potential tumor formation in feline leukemia-infected cats is another complication. FeLV-positive cats reportedly have 62 times the risk of developing lymphoma over un-infected cats.
- Who is susceptible: All ages of domestic cats are susceptible to infection.
- Transmission: Transmission may be vertical (from queen to fetus or nursing kitten) or horizontal (from cat to cat). Feline leukemia virus is shed in high numbers in saliva, urine and other secretions. It is easily transmitted by shared dishes, mutual grooming and using shared litter areas. Fighting of un-neutered males provides a common means of transmission.
- Prevention: The presence of persistently shedding but clinically unaffected cats makes prevention difficult. Additionally, vaccines offer some level of protection but are by no means 100% effective. Cat owners should be encouraged to test new cats, keep cats indoors if possible, and keep cats current on vaccines to help minimize risk of infection. “Test and Removal” programs have nearly eliminated the disease from catteries, and have proven effective in reducing incidence of infection in many communities. In contaminated areas, clean-up is relatively simple due to the fragility of the virus outside the host’s body. Routine disinfection inactivates the virus, and exposure is unlikely provided cats are not allowed direct contact.
Cats: Diseases Prevented by our Non-core Vaccines
Feline Immunodeficiency Virus
FIV is the “cat version” of HIV. It is a feline-specific disease, so FIV cannot transmit to humans or other animals, but it is very genetically similar to the HIV virus. Just like in humans, the immunodeficiency virus does not usually cause illness by itself, but suppresses the immune system so that cats often succumb to other diseases.
- Clinical signs: Again, FIV infection alone does not result in outward clinical signs, although altered white blood cell counts are often noticed when diagnostic testing is performed. Clinical signs really can amount to anything, depending on the opportunistic infections acquired due to immune suppression. Oral lesions, upper respiratory signs, diarrhea, skin lesions, ocular disease, neurologic signs, and generalized illness (such as listlessness, fever, and wasting) are common due to secondary viral and bacterial infections. FIV positive cats also seem more susceptible to neoplastic disease (cancer) such as lymphosarcoma. Many cats live for years with the disease and show no signs of illness.
- Who is susceptible: All ages of cats are susceptible, and the disease has been identified as being worldwide in its distribution. More intact males are identified with the disease, most likely because of their more aggressive, territorial, and roaming behaviors.
- Transmission: Infection occurs primarily from transfer of bodily fluids between cats. Casual contact among cats rarely causes transmission. Transmission is common via bite wounds and mating, as well as by in-utero transfer from infected mothers to kittens. As in human HIV transmission; blood transfusion from an FIV- positive cat is a recognized mode of transmission (although rare due to testing).
- Prevention: Spaying and neutering helps remove the drive to roam and fight. Keeping cats indoors is also recommended. Isolation and testing of all incoming cats (regardless of age and health status) is recommended before introducing them into a household with other cats. Vaccines show some promise in preventing against infection, however several strains of the FIV virus have been isolated and it is unknown whether the vaccine is uniformly effective against all strains. Current testing capabilities allow us to only test for exposure to the virus (natural virus or inactivated vaccine virus). This creates a dilemma, in that vaccinated animals will test positive for FIV, whether they have the disease or not. For cats entering shelters this poses a real problem, since in many shelters, FIV-positive cats are euthanized. FIV vaccines are available at Prairie (through special order), but are not commonly recommended except in special circumstances. Talk to a doctor at Prairie if you have questions regarding the vaccine.
Feline Infectious Peritonitis
Feline Infections Peritonitis (FIP) is caused by a mutated form of feline coronavirus. Feline coronavirus infection is very common in cats, and disease is generally mild (manifesting as mild gastrointestinal illness). Immunity from infection is short-lived, and thus cats in a multi-cat situation commonly become re-infected and intermittently shed the virus in feces. Studies have shown that population densities of 3 or more cats often maintain the virus in the population indefinitely. The “wild”-type strains of feline coronavirus rarely cause problems except in young kittens. In populations where the “wild”-type persists, however, opportunity occasionally arises for the virus to mutate within cats to the FIP-form of the virus. The mutated form results in systemic spread and often fatal disease. It is unknown what causes the wild-type coronavirus to spontaneously mutate to the FIP-form.
- Clinical signs: As mentioned, wild-type coronavirus may cause transient, mild gastrointestinal signs (mainly mild diarrhea). The FIP-mutant-type of coronavirus results in an overwhelming immune response to the virus, which often leads to death. In other words, the fatality of the disease is thought to result from the immune-mediated response, not the effects of the virus itself. Circulating viral particles are attacked by the body’s natural defenses (antibodies and neutrophils) in attempts to clear the virus. For an unknown reason, the body goes out of control in its immune response, and huge numbers of neutrophils lead to vasculitis, vessel leakage, and exudate (pus) formation around thoracic and abdominal organs. This often leads to organ collapse and death. The central nervous system and eyes may also become affected. Actual signs are variable and often vague, and may include wasting, diarrhea, vomiting, dyspnea, ocular changes and/or central nervous system signs.
- Who is susceptible: FIP has been identified in domestic cats worldwide, and has also been seen in some wild species of cats in captivity. Cats 3 months to 3 years old appear to be the most susceptible.
- Transmission: Transmission of the wild-type coronavirus is through fecal-oral transmission. Mutation to the FIP form is thought to occur within an individual cat. The FIP form of the virus is probably not transmitted from cat to cat; however researchers theorize that the wild-type coronavirus that can be shed from FIP-infected cats may be more prone to mutation.
- Prevention: Early vaccines (injectable forms) made antibody that actually exacerbated the disease. More recent vaccines come in an intra-nasal form, but efficacy of the vaccine is reportedly low. Routine disinfection and frequent cleaning of litter boxes in multi-cat households provides a means of transmission prevention. Coronaviruses are susceptible to most available disinfectants.
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