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FIV stands for “feline immunodeficiency virus,” just as HIV stands for human immunodeficiency virus. In fact, these two viruses are closely related and much of the general information that has become common knowledge for HIV also holds true for FIV.  FIV is a virus that causes AIDS in cats; however, there is a long asymptomatic period before AIDS occurs and our job is to prolong this asymptomatic period. The average life expectancy from the time of diagnosis for FIV is 5 years. Humans cannot be infected with FIV; FIV is a cats-only infection.

How Is FIV Diagnosed?

Most of the time, infection from FIV is discovered using a screening test performed in your veterinarian’s office or from a blood panel run at your veterinarian’s reference laboratory. Once a cat has been identified as positive by a screening test, a follow-up confirmation test called a “Western Blot”  is the next step. Once this test is positive, the cat is considered to be truly infected.

It should be noted that administration of the new vaccine recently released for commercial use will cause a cat to test positive on both of the above tests. We do not currently have a test that will distinguish a vaccinated cat from a truly positive cat.

My hospital is not currently recommending this vaccine for now.
If you are like most of the cat-owning community, you may have a vague familiarity with the FIV virus but are unclear on the details. You may not even be sure about the difference between the FIV virus and the FeLV virus, and you rely on your veterinarian to tell you what you need to know.

Fortunately, for most cat owners the FIV virus has been an academic matter. A new kitten receives a screening test around age 6 months. Cats are often re-tested when they are ill, but since most of our feline patients live their entire lives indoors, the FIV virus is not of much concern.

For outdoor cats, it is a whole other story. The FIV virus is spread by bite wounds between cats.  Adult cats, rather than kittens, are at risk. The American Association of Feline Practitioners recommends that outdoor cats be tested annually for this virus and for the Feline Leukemia Virus (the “FeLV” virus).

FIV, like HIV, can live in its host’s body for years before leading to a life-threatening AIDS situation. Ultimately, FIV is suppressive to the immune system and the average life expectancy from the time of diagnosis is 5 years.
In August 2002, Fort Dodge Animal Health released a vaccine for FIV and promoted it heavily. My hospital has looked long and hard at this vaccine which, on the surface, seems like a good idea for outdoor cats or cats living with FIV-positive housemate cats. I choose to say no to this vaccine at least until more information is available. I’m happy to list the features of the product that leave us with reservations.

• There are five strains of FIV virus, called “Clades.” The vaccine was made using Clades A and D and tested using Clade A. Clade B, for example, is a very common strain in most regions of the United States and no testing of the vaccine has been performed thus far against Clade B.  This means that a pet owner might wrongly believe they were protecting their cat fully against the FIV virus with this vaccine. California has both Clades A and B.
• The FIV vaccine is “adjuvanted.” An adjuvant is an additive used with killed vaccines to improve their ability to stimulate the immune system.  Unfortunately, adjuvanted vaccines have been implicated in the development of certain tumors in the cat.  My hospital currently does not use adjuvanted vaccines for cats, and has no desire to administer a vaccine that stimulates tumor growth even under rare circumstances.
• Vaccinated cats will test positive on all current methods of testing for the FIV virus. This means it will no longer be possible to distinguish vaccinated cats from truly infected cats. The vaccine is advertised at protecting 82% of cats, which means 18% can still be infected. This is nearly a one in five chance of unknowingly having an infected cat.

FIV infection is preventable by keeping cats indoors and preventing cat fights.
We choose to wait this out a bit and see how the FIV vaccination is faring a year or so hence.

How Did My Cat Get Infected?

The major route of virus transmission is by the deep bite wounds that occur during fighting. There are other means of spreading the virus but they are less common. Mother cats cannot readily infect their kittens (except in the initial stages of infection). FIV can be transmitted sexually and via improperly screened blood transfusions.  Casual contact such as sharing food bowls or snuggling is very unlikely to be associated with transmission.
Isolation of an FIV+ cat is not necessary in a stable household unless the FIV+ cat is likely to fight with the other residents.

What Do I Do Now?
Some lifestyle changes will probably be needed now that you know you have an FIV+ cat.

• Keep Your Cat Indoors Only
  Now that you know your cat has an infectious disease, the responsible thing is to prevent the spread of this disease in your community. This means that your cat will need to begin life as an indoor cat. Cats who are used to living outdoors will make a fuss about being allowed outside. It is crucial that you do not give in as this will simply reinforce the crying and fussing. If you just allow the fussing to run its course, it will cease and the cat will get used to its new indoor only life.Cats who are inclined to slip past people entering the home when the door is open can be managed by leaving them in a closed room when someone is out of the house. This way, when the person arrives home, the cat does not have access to the front door.
• No Raw Foods
  There are currently numerous fad diets involving raw foods for pets. It is crucial that one not succumb to these popular recommendations when it comes to the FIV+ cat.  Uncooked foods, meats especially, can include parasites and pathogens that a cat with a normal immune system might be able to handle but an FIV+ cat might not. Stick to the major reputable cat food brands.
• Vaccination
  Vaccination should be continued for these cats just as they are for other cats. Some experts recommend using only killed vaccines to avoid any possible reversion to virulence of the live vaccine virus strains. This has not panned out as a problem in reality, plus the killed vaccines have been associated with vaccine-associated fibrosarcomas, an additional problem an FIV+ cat does not need.  We still recommend live virus vaccines for FIV+ cats just as we do for FIV- cats.

Parasite Control
The last thing an FIV+ cat needs is fleas, worms, or mites, especially now that he is going to be an indoor cat. There are numerous effective products on the market for parasite control. Consult with your veterinarian about which parasites you should be especially concerned with and which product is right for you.

• Immune-Stimulating Agents
  There are numerous products on the market claiming to stimulate the immune system of the FIV+ cat. These include Acemannan, levamisole, Immunoregulin®  http://www.neogen.com/immunoregulin.htm), and Interferon Alpha. None of these products have been shown definitively to be helpful though it appears that they certainly do not do any harm. Our hospital recommends Interferon Alpha for asymptomatic cats as it is relatively inexpensive and our impression is that it helps. Interferon alpha is used in an extremely dilute form (not the much higher anti-viral doses) and is used as a salty liquid added to the cat’s food or administered orally on a daily basis.
• General Monitoring
  While a non-geriatric FIV- cat should have an annual examination, the FIV+ cat should have a check-up twice a year. Annually, a full blood panel and urinalysis is prudent. Also, it is important to be vigilant of any changes in the FIV+ cat. Small changes that one might not think would be significant in an FIV- cat, should probably be thoroughly explored in an FIV+ cat.

THE FELINE IMMUNODEFICIENCY VIRUS IS NOT TRANSMISSIBLE TO HUMANS IN ANY WAY.

What About Medications Used in HIV+ Humans?

AZT (brand name Retrovir®) is a prominent antiviral medication for the treatment of human HIV infection. Tests in FIV+ cats indicate that those with either neurologic signs or with stomatitis (oral inflammation) may benefit most. At this time at least (in cats), AZT seems to be something to save for when symptoms of viral infection appear. There are some bone marrow issues with red blood production and some periodic monitoring tests are advisable. If problems arise, fortunately, they are reversible and should resolve with a few days of discontinuing medication.
Drugs other than AZT seem to have more potential for toxicity and are not recommended for feline use.

The Immune-Suppressed Owner

Immune-suppressed cats and immune-suppressed owners do not mix well. Those who are immune suppressed, be they human or non-human, are inclined to become infected with opportunistic organisms, and in turn shed larger numbers of those organisms than one might naturally come into contact with in the environment. This means that someone who is immune-suppressed (human or not) can serve as an amplifier for infectious agents. An immune-suppressed cat can increase an immune-suppressed human’s exposure to infectious agents and vice versa. This is obviously not a good situation. The same is true for multiple immune-suppressed cats living together. If possible, there should be only one immune-suppressed individual per home.

Feline leukemia virus, a retrovirus, is a common infection of cats. It is the cause of more cat deaths, directly or indirectly, than any other organism and is widespread in the cat population.

Disease Transmission
Feline leukemia virus infection (FeLV) can be transmitted several ways:
a. by the saliva of infected cats contaminating the eye, mouth, and nose membranes of non-infected cats via licking.
b. by passing infected blood to non-infected cats.
c. from mother to fetuses (developing kittens) during pregnancy.

Disease
Most infected cats eliminate the virus and become immune. In those cats that do not develop immunity, the virus spreads to the bone marrow.

Proliferative and degenerative diseases may occur in any of the tissues invaded by the virus, or the virus may be indirectly responsible for other illnesses because of its immunosuppressive effect. A large percentage of the cats that are exposed to the virus will have latent (hidden) infections and will be capable of transmitting the disease in saliva, tears, and urine. Some of these latent carriers will become clinically ill when stressed.

Diagnostic Tests
Necessary diagnostic tests may include blood chemistry, hematology, radiography, bone marrow aspiration, ophthalmoscopy, and specialized antibody tests.

Treatment
a. There is no effective treatment for the myeloproliferative (bone marrow) form of leukemia. Treatment is mainly supportive, and may require blood transfusions, prednisone, and anabolic steroids.
b. FeLV cancer (lymphoma) has a better response to therapy than the myeloproliferative diseases do. Treatment may include chemotherapy, glucocorticoids, interferon, Protein A, and supportive treatment.

Prognosis
Eighty-five percent of cats with FeLV infection die within 3 years of the diagnosis.

Prevention Of FeLV
There are several preventive measures that can be taken to decrease the risk of contracting FeLV.
a. Cats can be FeLV tested, and then vaccinated if they are negative. Vaccination is recommended for high risk cats only. FeLV vaccination of infected cats does not affect the carrier state, the capacity to infect other cats, or the development of disease in the infected cats. Vaccination may also be associated with adverse events. (Duration of immunity may vary from fifteen weeks to three years.)

—Kittens may be tested at any age. However, infection in newborn kittens may not be detected until weeks to months after birth. Therefore, several FeLV tests during the first six months of life may be necessary to feel completely “safe” about a negative test result.

—-All kittens or adult cats that test negative by the first ELISA screening test – but with a known or suspected exposure to FeLV – should be retested. This is done to rule out possible negative results obtained during incubation of the FeLV virus. Although the majority of cats will test positive within several weeks, final retest of negative cats should be no sooner than 90 days post-exposure.

b. In large catteries, a test and removal program can be instituted.
c. Multi-cat households with FeLV positive cats should be maintained as a closed colony. (No new cats should be brought into the household, to prevent the spread of infection to the new arrivals.)

Notes:
Retroviruses are unstable, live for only minutes outside the cat’s body, and are readily destroyed by most disinfectants.

Because the feline leukemia virus is so unstable, a new, healthy cat can be brought safely into a “contaminated” house within days of the departure of a FeLV infected cat.

Heartworm (Dirofilaria immitis) is a fairly large worm up to 14 inches long that, in adulthood, lives in the heart and pulmonary arteries of an infected dog. Dogs aquire this infection through mosquito bites as mosquitoes readily pick up larval heartworms from infected dogs and carry them to new dogs. Some geographic areas have severe heartworm problems while other areas have none. In order for the parasite to establish its presence in an area, the following conditions must be met:

• Types of mosquitoes capable of carrying larval heartworms must be present
• The weather must be warm enough to allow heartworm larval development within the mosquito
• There must be infected dogs (or coyotes) in the area
• There must be vulnerable host dogs in the area

When these conditions come together, an area becomes endemic for heartworm disease.

THE DETAILED VERSION OF THE HEARTWORM STORY:
LET’S FOLLOW THE WORM’S LIFE CYCLE
THE ADULT HEARTWORM

The adult heartworm is fairly large, several inches in length, and it prefers to live, not in the heart, but in the pulmonary arteries. It swims into a cozy tubular artery, where it is massaged and nourished by the blood coursing past it. In the pulmonary arteries of an infected dog, the worm’s presence generates a strong inflammatory response and a tendency for blood to inappropriately clot. If enough worms are present, the heart must work extra hard to pump blood through the plugged up arteries.

If the worm infection is a heavy one (over 25 worms for a 40 lb dog), the worms begin to back up into the right ventricle (the chamber that pumps blood through the lung). The worms actually take up a significant amount of space within the heart, leading to less blood being pumped.

When over 50 worms are present, the ventricle is full and the atrium, the chamber receiving blood from the rest of the body begins to contain worms.

When over 100 worms are present, the entire right side of the heart is filled with worms and there is very little room for any blood to be pumped. This drastic phenomenon is called Caval Syndrome and most dogs do not survive it.

MICROFILARIAE (First Stage Larvae)

With adult male and female worms present, mating begins to occur. Heartworms do not lay eggs like other worm parasites; instead they give live birth and the baby worms are called Microfilariae. Microfilariae are released into the circulatory system in hope that they will be slurped up by a mosquito taking a blood meal and carried to a new host. Microfilariae may live up to 2 years within the host dog in whom they were born; if after this period a mosquito has not picked them up, they die of old age. Microfilariae may also be transmitted across the placental barrier to unborn puppies if the mother dog is infected with heartworm. It is important to realize that such puppies will not develop adult heartworms or heartworm disease from these microfilariae; in order for a heartworm to reach adulthood, it must be passed through a mosquito.

Parasitic worms have 5 larval stages and are termed L1, L2, L3, etc. Heartworm microfilariae are first stage larvae: L1s.

Note: Heartgard30 and Interceptor, the main heartworm preventives available commercially, will kill microfilariae. Dogs on heartworm preventive, even if infected with adult heartworms, will not test positive for microfilariae.

INSIDE THE MOSQUITO

Within the mosquito’s body, the microfilariae will develop to L2s and finally to L3s, the stage capable of infecting a new dog. How long this takes depends on the environmental conditions. In general, it takes a few weeks. A minimum environmental temperature of 57 degrees F is required throughout this period. The process goes faster in warmer weather.

INFECTING A NEW DOG

When a dog is bitten by an infected mosquito, the L3 is not deposited directly into the dog’s bloodstream. Instead, it is deposited in a tiny drop of mosquito “spit” adjacent to the mosquito bite. For transmission to occur, there must be adequate humidity to prevent evaporation of this fluid droplet before the L3s can swim through the mosquito bite and into the new host.

Once safely inside the new host, the L3 will spend the next week or two developing into an L4 within the host’s skin.

The L4 will live in the skin for 3 months or so until it develops to the L5 stage and is ready to enter the host’s circulatory system. The L5, which is actually a young adult, migrates to the heart and out into the pulmonary arteries (if there is room) where it will mate, approximately 5 to 7 months after first entering the new host.

Note: L3s are readily killed by Interceptor but not by Heartgard30. Interceptor and Heartgard30 both act primarily on the L4s living in the skin. After a dose of either medication, any L4s present will be wiped out. Heartgard30 is also able to kill the younger L5s.

Canine parvovirus is a highly contagious virus that can affect all dogs, but unvaccinated dogs and puppies younger than four months old are the most at risk. Dogs that are ill from canine parvovirus infection are often said to have “parvo.” The virus affects dogs’ gastrointestinal tracts and is spread by direct dog-to-dog contact and contact with contaminated stool, environments, or people. The virus can also contaminate kennel surfaces, food and water bowls, collars and leashes, and the hands and clothing of people who handle infected dogs. It is resistant to heat, cold, humidity, and drying, and can survive in the environment for long periods of time. Even trace amounts of stool containing parvovirus may infect other dogs that come into the infected environment. It can be transmitted from place to place on the hair or feet of dogs or via contaminated cages, shoes, or other objects.

Signs of parvovirus

Some of the signs of parvovirus include:

• lethargy
• loss of appetite
• Fever
• vomiting
• severe, often bloody, diarrhea.

Vomiting and diarrhea can cause rapid dehydration, and most deaths from parvovirus occur within 48 to 72 hours following the onset of signs.
If your puppy or dog shows any of these signs, you should contact your veterinarian immediately.

Treatment

While no specific drug is available that will kill the virus in infected dogs, treatment consists primarily of efforts to combat dehydration by replacing electrolyte and fluid losses, controlling vomiting and diarrhea, and preventing secondary infections until the dog’s immune system is able to fight the virus. Due to the highly contagious nature of parvovirus, infected dogs must be isolated in order to prevent the spread of the infection.

Preventing parvovirus

The best way to prevent parvovirus is through good hygiene and vaccination. Make sure to get your puppies vaccinated, and that your adult dogs are kept up to date on their parvovirus vaccination. Talk to your veterinarian about a canine parvovirus vaccination plan that is best for your pet. Until a puppy has received its complete series of vaccinations, pet owners should use caution when bringing their pet to places where young puppies or dogs with unknown vaccination histories congregate.

What causes Pancreatitis?

There are many factors that may predispose your pet to pancreatitis; these include obesity, high-fat diet; concurrent disease, such as diabetes or Cushing’s Syndrome; certain medications or toxins; and infection.
Dietary indiscretion (e.g., eating inappropriate materials, garbage, or table food) is a leading cause of pancreatitis in dogs– and those dogs that have experienced dietary indiscretion are known to be up to 10 times more likely to develop pancreatitis.

Pancreatitis in cats is often secondary or accompanied by other disease, such as inflammatory bowel disease (IBD), diabetes, or liver disease. Other causes in cats include infection; injury; and certain medications, toxins, and insecticides.

Symptoms of Pancreatitis can differ among dogs and cats:

Dogs with Pancreatitis will often stop eating and drinking because of the pain associated with this disease.
Canine Symptoms:

• Abdominal Pain
• Swollen abdomen
• Abnormal posture; arching of the back
• Diarrhea
• Vomiting
• Lethargy
• Fever
• Restlessness
• Gagging

Cats are instinctively wired to hide signs of sickness, and cats with pancreatitis are no exception. Typically, they have vague signs, especially as compared to dogs, so it isn’t often obvious to their owners that they are sick.
Feline Symptoms may include:

• Lethargy
• Decrease in appetite
• Weight Loss
• Vomiting
• Diarrhea
• Abdominal pain
• Fever

 Diagnostics: 
Your veterinarian will take a complete history and preform a thorough physical exam of your pet. Additionally diagnostic tests will be required to determine if your pet has pancreatitis. These may include:

• Chemistry tests – to evaluate Kidney, Liver, and pancreatic disease or dysfunction, as well as sugar levels
• A complete blood count (CBC)– to screen for infection, inflammation, or anemia and other blood-related conditions.
• Electrolyte Tests – to ensure your pet isn’t dehydrated or suffering from an electrolyte imbalance.
• Pancreas-Specific tests– to help diagnose or rule out the disease.

Treatment:

Your Veterinarian will suggest a treatment plan that is specific to your pet. The treatment depends on the severity of the disease and may include:

• Hospitalization at the clinic
• Fluid therapy and electrolytes
• Pain medication
• Antivomiting medication
• Antibiotics
• Nutritional support
• Treatment of other concurrent diseases
• Other Medications, depending on your pets symptoms

How do I work to prevent Pancreatitis:

• DON’T let your dog become overweight – weight management is just as important for our four-legged friends as it is for us!
• AVOID High-fat diets
• AVOID giving your dog table scraps, especially if she isn’t accustomed to eating people food – We understand it is difficult but it is not healthy for your pet. Watch this brief video of Household Foods and Hazards to avoid.
• MAKE sure you talk with your veterinarian about all of your pets medications
• DON’T let your dog get into the trash!

If you are worried that your dog may be showing signs or symptoms of pancreatitis, Please see your veterinarian immediately.

*All Information received from IDEXX Laboratories Pamphlet on Pancreatitis – “The Facts about Pancreatitis and your Pet”