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Subject: rec.pets.cats:  Feline Leukemia FAQ
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                        Feline Leukemia Virus FAQ

  (dedicated to Oliver and countless other cats whose lives have been
  mercilessly shortened by this virus. We will all meet them again at
  the Rainbow Bridge.)

  Contents:
    * General information about FeLV
    * If your cat has tested positive
    * References
    * Other FeLV sites

  Last updated April 20, 1998.

  Authors:
  Written by Erin Miller [ [email protected]] with help from James
      Golczewski, PhD; Edwin Barkdoll, DVM-to-be; Cindy Tittle Moore;
      Jeff Parke, DVM; C.M. Newell, DVM; Barb French; Richard Kinoshita;
      and Ann Huber. Additional thanks to Wilf Leblanc, Dan Kozisek,
      Karen Kolling, Isako Honshino, Patty Winter, Harold Lemon, Jill
      Kronstadt, and many members of the Cat Fanciers' Internet Mailing
      List for their comments.

  The purpose of this FAQ is to answer frequently asked questions about
  the Feline Leukemia Virus (FeLV). The Feline Leukemia Virus is a virus
  which suppresses your cat's immune system. A cat that becomes infected
  with the virus becomes susceptible to many ailments or breakdowns in
  its system. The virus was somewhat inappropriately named because it is
  different than the disease Feline Leukemia. A cat that tests positive
  for the virus will not necessarily contract the disease Feline
  Leukemia. However, cats that do test positive for the virus are more
  likely to catch any one of a number of diseases including, but not
  limited to, leukemia, lymphoma or opportunistic infections. This FAQ
  is divided into two parts; the first consists of information every cat
  owner should know or should ask about the virus. The second part is
  information for people whose cats have tested positive for the virus.
    _________________________________________________________________

PART I: General Information about FeLV

  What is Feline Leukemia Virus and can I catch it?
  Feline Leukemia Virus is a virus that is specific to cats only. It is
      considered to be the most common cause of serious illness and
      death in domestic cats. It causes a breakdown in your cat's immune
      system causing your cat to become susceptible to many diseases
      which it might otherwise be able to fight off. It CANNOT be
      transmitted to humans (including children) nor can it be
      transmitted to other species such as dogs. The National Cancer
      Institute and the National Institutes of Health have written a
      CancerNet Factsheet which is available via gopher. See the
      References section for more information on this.

  I've heard FELV is like AIDS. Can I catch AIDS or anything else from
  it?
  People often use the "it's like AIDS" phrase to describe a number of
      illnesses in the animal (and human) community with the idea that
      most people know so much about AIDS that this analogy is useful.
      Unfortunately most people don't know much about AIDS and the
      resulting effect is to scare people out of their wits and have
      them dump their cats or dogs at the nearest pound because they are
      so deathly afraid of AIDS. They are similar to AIDS in that they
      affect and weaken the body's immune system. The ONLY similarity
      between FeLV, FIV (Feline Immunodeficiency Virus) and FIP (Feline
      Infectious Peritonitis) is in their genetic makeup. All are RNA
      (as opposed to DNA) viruses, and FeLV and FIV are what are known
      as "retroviruses." FIP is a "coronavirus." (See the FIP FAQ for
      more information on this disease).

  What is a retrovirus?
  Retroviruses carry with them an enzyme that causes a process to occur
      in the DNA known as "reverse transcription." RNA normally pairs up
      with DNA, copies itself, and thus increases/replicates itself.
      When an RNA retrovirus does this, it fools the DNA to copy *it*,
      instead of the normal RNA, thus causing even more of the
      retrovirus to be created. So as long as a particular cell is
      affected with the retrovirus, that cell will be affected for its
      whole life. One would have to kill the cell before it reproduces
      to eliminate any chance of that cell making any more FeLV or FIV
      RNA. This is one of the reasons why it is so difficult to get rid
      of, because you must kill all the cells which contain the virus,
      and attempting to do this may either kill the animal itself, or it
      is simply impossible to tell which cells have the virus in the
      first place. Basically, a retrovirus is a parasite at the genetic
      level, a DNA-tapeworm, if you will.

  How is it transmitted?
  FeLV is transmitted via saliva, mucus, urine, feces and blood. This
      means mutual grooming and biting/fighting are the most likely
      methods of transmission, although sneezing, hissing, sharing
      food/water bowls and sharing litter boxes are also possible means
      of transmission.

  Will I infect my healthy cat if I pet an FeLV+ cat, then pet my cat?
  No. Not unless you were to go immediately from one cat to another, and
      have wet saliva, urine or blood on your hand. Even then the
      chances would be slim. FeLV needs to be transferred through the
      media above, and will not live long outside the host (the infected
      cat). Warm, dry environments will deactivate the virus and common
      household detergents and disinfectants will eliminate it from any
      contacted surfaces. If you wash your hands with soap after
      touching an infected cat, you will not infect an FeLV negative
      cat.

  What does the virus do to a cat?
  In sum, once the virus gains entry (usually via saliva or mucus
      membranes) it will reproduce in the lymph tissue which is your
      cat's first system of immune defense. Some cats are able to mount
      a successful immune response against it and defeat the virus at
      this stage. In cats who don't successfully destroy the virus here,
      the virus will then move into the bone marrow where red and white
      blood cells are produced. It may stay latent in the marrow for
      many years. After that it will attack other tissues, including
      possibly causing a breakdown in several stages of the immune
      response system.

  Is there a vaccine?
  Yes, there are several commercial vaccines available. Unfortunately
      the USDA does not have standard requirements for FeLV vaccines, so
      different manufacturers can publish 'Effectiveness Ratings' which
      cannot be compared with each other due to a lack of uniformity in
      testing terms and requirements. Estimating the effectiveness of
      the vaccines is difficult and most vets I've spoken with estimate
      them to have ~75-85% effectiveness (this means cats challenged
      with the virus will fight off infection 7-8 times out of ten).
      Published studies show that there are irreconcilable differences
      and bias in Effectiveness Ratings put out by the manufacturers so
      currently it is impossible to estimate the actual effectiveness of
      and between vaccines. Suffice it to say that your cat is MUCH
      better off trying to fight the virus having received the vaccine,
      but the vaccine is not 100% effective so you should not expose
      your cat to undue risks. (Note: NO vaccine, whether it be for
      cats, dogs or people, is 100% effective. Some are about close to
      being as fully effective as possible, however the FeLV vaccine is
      not one of them).
      Since writing the first version of this FAQ, I've had a number of
      people tell me that a cat has only a 30% likelihood of catching
      the disease, and even then if only in persistent close contact. I
      have found nothing in the recent literature to support this claim,
      and every veterinarian I have spoken with states that the
      likelihood of becoming infected depends on the level of exposure,
      which vary in different locales and situations. Since most tests
      are done in controlled situations, it would be impossible to come
      up with true "real world" statistics. In one vet's words "But what
      if it is only 30%? Would you stop wearing seat belts if there was
      only a 30% chance of serious accidents if you commuted in a car
      every day? I hope the odds are far less than that ... and yet I
      still hope you are taking the appropriate safety cautions. Unless
      the vaccine has been proven to cause serious harm, it is a good
      precaution to take, regardless of the percent chance of disease
      transmission."

  If I don't get my cat vaccinated, what are its natural defenses
  against the virus?
  According to the literature, neonatal kittens are 100% susceptible to
      catching the virus from one exposure. 8-week-old weanlings are 85%
      susceptible from one exposure. There is serious debate over the
      likelihood of non-vaccinated, healthy adult cats becoming infected
      with the virus but it seems that ~40% of cats exposed become
      immune, ~30 percent become persistently infected (show acute signs
      of a related-disease) and ~30 percent become infected, but the
      virus is latent in their system. (Hardy, et al, 1980).

  Is the vaccine expensive and how often do my cats need to be
  vaccinated?
  After your cat has gone through its more elaborate set of
      kitten-shots, the FeLV vaccine should be given once a year. If you
      adopt an adult cat and don't know if it has been vaccinated for
      FeLV, start it immediately on its annual shots. If you are unsure
      if your adult cat needs be vaccinated, talk to your vet. Prices
      vary between vets, locally and nationally. I surveyed readers of
      rec.pets.cats and contacted vets around the country and found that
      prices for the vaccination alone cost between $9 and $30 dollars.
      The average was $18 (not including the vet-visit charge). It seems
      that the FeLV test costs about the same, but I didn't do a
      full-scale survey.

  If I get my cat vaccinated, isn't there a chance that it will catch
  the virus from the vaccine?
  No. As of July 1992, all of the vaccines which are approved for sale
      in the United States are incapable of causing a positive FeLV test
      result. (Sorry, but I don't have figures for vaccines in other
      countries. If anyone does, feel free to append them onto this
      FAQ.)

  Is there any risk in getting my cats vaccinated?
  There is always a risk that your cat may have a bad reaction to a
      vaccine, ANY vaccine. It is a good idea to wait in your vet's
      waiting room for 30 minutes after receiving a vaccination, ANY
      vaccination, to make sure your cat does not have an adverse
      reaction, and if it does the vets will be on hand to deal with the
      situation.
      There is also some evidence that vaccinations in general may be
      the cause of tumors (known as postvaccinal sarcomas or
      fibrosarcomas). The chance of this happening is estimated to be
      approximately 1-2 in 10,000, but you should be aware of it
      nonetheless. This has not been limited to FeLV vaccines, in fact
      it was originally thought to pertain solely to rabies vaccines,
      but this is not thought to be the case any more. Since this form
      of cancer seems to have a high recurrence rate, and little is
      known about it, if you have *strictly* indoor-only cats, you may
      want to discuss with your vet if the risk of fibrosarcoma is
      greater than the risk of being exposed to FeLV if the cat gets
      out. This is an individual decision that will be different for
      each household. You should contact your vet immediately if you
      notice any lumps in the vaccine injection area.

  Do I have to get my cats vaccinated?
  No one can force you to vaccinate your pets, though there are laws in
      some areas regarding certain diseases like rabies. Check with your
      vet to see what vaccines are required in your area.

  My cats are indoors-only. Why should I bother getting them vaccinated?
  The answer to this question all boils down to a risk/benefit
      assessment.
      If you live in a high-rise, do not plan on moving in the next
      year, and do not plan on exposing your cat to other cats (such as
      getting a new kitten, or temporarily housing a stray), then there
      is really no need to get the cat vaccinated. If it is somehow
      possible for your cat to make it to the outside world, whether it
      be because of a break-in, or a landlord who forgets to close the
      window they just fixed, or a visitor doesn't realize the cat is
      not allowed outside (all of which are real-life cases of people I
      know whose indoor-only cats have gotten outside) then your cat is
      at SOME risk. Many people who lived through Hurricane Andrew or
      the LA Earthquake can tell you that some of their indoors-only
      cats ended up on the street for days. Fortunately disasters like
      these are infrequent, but the point is accidents can happen. In
      the few hours or days that your cat is outside it could come in
      contact with an infected cat, and it is better to give your cat
      that 75-85% boost to its natural resistance.
      But, some people feel the risk of adverse reaction and possible
      fibrosarcomas from vaccinating are not worth the risk if the cat
      is not likely to go be exposed to FeLV+ cats, even if it did get
      outside for a short period. What YOU as the cat's owner (not your
      vet, not your cat's breeder, not your friend of a friend who knows
      a lot about cats, and not someone who wrote something you read on
      the internet) must decide is how much risk is there for your cat
      getting out and being exposed, and is that risk worth the other
      risks associated with the vaccine?

  My cat is a purebred, and I've heard the vaccine should not be given
  to purebreds. The breeder I bought the cat from discourages getting
  the vaccine.
  This is a touchy subject because there is often the general feeling
      among vets that many breeders don't know what they are doing, and
      the feeling among breeders that vets don't know much about
      purebreds. There is probably a little bit of truth to both sides.
      It is true that some breeders may think they understand veterinary
      medicine better than they really do, and unfortunately rely on
      word-of-mouth advice of other breeders rather than vets (eg: "Jane
      Smith has been breeding for 15 years and she knows a lot so if she
      doesn't like this vaccine, it must be bad"). But it is also true
      that most vets do not deal specifically with purebred issues.
      There is no course in vet school called "Purebreds 101" and vets
      are often just as guilty as anyone in misidentifying mixed breeds
      as purebreds, of being too quick to diagnose a "breed specific"
      illness with less data than if they would if the cat were not a
      purebred, or of not being aware of conditions which may affect one
      breed more than another.
      Keep in mind that some veterinarians are also breeders, or work
      within the CFA, TICA, ACFA (AKC for dogs) or other purebred
      registries, and these vets are most likely going to be more
      knowledgeable about conditions which are more common to certain
      breeds. Also remember that not all purebreds are the same, each
      breed is different and has its own characteristics. Just like you
      can't say "don't vaccinate Europeans for smallpox," because there
      are *many* different cultural and ethnic groups in Europe.
      The immune system of purebred cats has NEVER been tested to
      determine if it is different than that of mixed breed cats. It is
      impossible to state one way or another if the purebred immune
      system, because of inbreeding, has any reason to adversely react
      to vaccines that are tested on a largely mixed-breed cat
      population. Some people feel there is a significant difference
      between the two based on antecdotal evidence and won't vaccinate
      for that reason, and some people feel this is nonsense.
      But that doesn't answer the question because this one is going to
      have to be answered by you and your own gut feeling. Who do you
      trust more with the combined necessary knowledge of vaccines, as
      well as about your purebred? Talk to your breeder and see if s/he
      is aware of the vet literature, or is repeating word-of-mouth
      arguments. Many of them are well aware, many read the literature
      more than vets do, so don't be afraid to ask them why they hold
      the opinions they do. Talk to your vet and ask how familiar they
      are with your partiuclar breed of cat as well as purebreds in
      general. Get a feel for both. Keep in mind that many breeders do
      not vaccinate their own breeding cats because FeLV vaccines can
      cause miscarriages and stillbirths, or it may just be cheaper for
      the breeder to test their cattery every year and every cat that
      comes into the cattery rather than to vaccinate, especially as
      cats from a cattery are less likely to escape to the outside world
      (remember the risk/benefit assessment above). Make sure you find
      out exactly why the breeder does not recommend the vaccine as it
      may very well be that the breeder has had numerous negative
      experiences with the vaccine in his/her particular line of cats,
      and that your cat may be genetically predisposed to have a bad
      reaction. If this is the case, you should still discuss the matter
      with your vet, and it may be best not to get the vaccine.

  My cat gets sick after it gets vaccinations. Why should I put my cat
  through that?
  Some cats do have bad reactions to vaccines. However, it is better to
      have a cat sick for one day per year from being vaccinated than to
      have it die a miserable death from an FeLV-related disease. If
      your cat has a bad reaction to a shot, ANY shot, and the reaction
      lasts more than 12-24 hours, you should immediately bring your cat
      to the vet. Even if your cat has a mild reaction, you should at
      least discuss the matter to see what are the best options for next
      year's vaccinations. It may be best to spread your cat's annual
      vaccinations out over a few months, or have them all administered
      at once. If your cat has had a *very* bad reaction, it very well
      may be best to discontinue vaccinating for FeLV. Definitely
      discuss this with your vet.

  I already have a cat(s) and I found another which I want to bring
  home. What precautions should I take regarding FeLV (and other
  diseases)?
  This depends on the environment the new cat comes from. If it is a
      stray, or from a shelter which does not routinely test for the
      viruses (make sure you ask this of any shelter you visit), or from
      a household where you have reason to doubt the person has had the
      cat tested/vaccinated, then keep the new cat separated from yours
      until you can have a vet examine it for many things. Keep it in a
      separate room and provide its own food dish, water bowl and
      litter. DO NOT let your cats share any of these things, or share
      the same space, until your vet checks out the new one. If it is a
      stray cat, it may never have been vaccinated against FeLV and
      Rabies, or if it was a housecat it may be past its time for an
      update and have been exposed. Cats which have been on the street
      may also have fleas, tapeworm, ringworm or other parasites which
      are transmittable to you and your pets.
      One of the most unfortunate situations that occurs far too often
      is when someone, out of the kindness of their heart, takes in a
      stray or unwanted cat -- either permanently or in the hopes of
      finding it another home. This is often done spur-of-the-moment,
      and unfortunately sometimes has dire consequences. If you find a
      cat in a bad situation and you want to help it, keep it isolated
      or ask your vet to board it until all the test results have
      returned. It is never worth the lives of your current pets in an
      attempt to save another.

  How is FeLV detected?
  Your vet will do a blood test; there are two types of blood tests
      which can be performed. Some vets will automatically do one of the
      tests before vaccinating your cat to make sure it is not already
      positive for the virus. The first (ELISA test) is where the vet
      takes some of your cat's blood, mixes it with a chemical and
      watches for a color change. If the blood changes color then your
      cat has tested positive for the virus. False positives are not
      uncommon in this form of test, so if your cat tests positive it
      may be a good idea to have it retested. "Light positives" are
      where the treated blood only changes color slightly. This means
      your cat is infected with the virus, but the virus is not very
      active in its system. The second type (IFA test) involves sending
      the blood sample to a special lab. This lab tests to see if the
      virus is being produced in the bone marrow. If this second test is
      positive, it is unlikely that your cat will ever test negative.
      Below is a flow chart (from a lecture by Dr. William Hardy, U of
      Penn. Vet School) which depicts what you should do if your cat
      tests positive on the ELISA test:

    * If positive:
         + whether healthy or sick, confirm by Indirect Fluorescent
           Antibody test (IFA)
    * If negative:
         + if healthy and not exposed to a positive cat then no need to
           retest
         + if healthy but exposed to a positive cat then retest in 3
           months because the healthy cat may be incubating the virus.
         + if sick then confirm the ELISA test with an IFA test

  So some cats who test positive can later test negative?
  Yes. If you have a cat which tests positive on the ELISA test, you
      should immediately have an IFA test done. If it tests negative on
      the IFA test, you should have your cat retested with the ELISA
      test in 3 months. If a cat does not test negative again in roughly
      three months, chances are it will always test positive. Vets and
      virologists have devised an entire classification scheme of the
      different types of infected cats (transiently infected,
      persistently infected, etc.) based on the ELISA and IFA tests. It
      can be very confusing and if you are interested in learning the
      details you should consult with your vet regarding your particular
      cat's status.

  Is it possible for a cat to test negative when it really is positive?
  Unfortunately, yes. Although false negatives are not very common, they
      do occur, especially if you are dealing with a young kitten.
      Sometimes the cat has been recently exposed to FeLV, so the
      antibodies have not yet had enough time to build up enough of a
      response to appear on the test. To be absolutely sure a cat is not
      FeLV+ you should test it twice, a few weeks apart (the cat should
      remain isolated from other cats during this period, too, otherwise
      there is little point in doing a second test). The likelihood of
      getting a false negative is increased depending on the nature of
      the test. The ELISA test will show more false negatives than the
      IFA test. Some mail-order catalogues now offer FeLV testing kits
      using saliva or tears as the medium. These are more likely to
      trigger a false response than the ELISA test which uses blood.
      Fortunately, the false negative rate on the ELISA test (which is
      what most vet offices use for standard FeLV tests) is low enough
      that most people don't bother with the second test.

  How long does a cat who tests positive have to live?
  There is no set time period for how long an FeLV+ cat will live. One
      person on the internet said they had a cat which lived for 20
      years with the virus, while others have given dates as long as 10
      or 12 years, although these are probably extremes. I have not
      found any truly long-term studies to document, but it seems that
      of the studies done, 83% of FeLV+ cats do not live beyond 4 years.
      (Hardy, et al 1980). All cats which do not later test negative,
      but in all other ways are healthy, are carriers for the virus.
      Even though they do not have acute symptoms, they can still spread
      the virus to cats which are not infected. Often people do not have
      their cat tested for the presence of FeLV until the cat is
      noticeably sick, and by this time the FeLV-related disease may
      have progressed too far for the cat to recover.

  What are symptoms for which I should be on the lookout?
  Unfortunately, since FeLV is a retrovirus that attacks your cat's
      immune system, your cat can become ill from many things as a
      result. This makes looking for a 'sure sign' very difficult. Often
      the immune system is weak so your cat will become chronically
      infected with certain conditions such as stomatitis, gingivitis,
      oral ulcers, abscesses and non-healing wounds of the skin, upper
      respiratory infections or FIP. Some cats whose digestive tracts
      are affected have been described as staring at their food bowl
      seemingly unable to remember how to eat, or their breathing will
      be very difficult and loud. Basically, whenever your cat shows
      chronic, peculiar and/or unhealthy behavior, take it to a vet to
      be examined.

  My cat recently passed away from FeLV. How long should I wait before
  getting another cat and are there any special precautions I should
  take?
  Well, your own grief issues aside, from a medical point of view you do
      not need to wait very long. The virus is fragile outside the host,
      and I know of one vet who has even stated that it would be safe
      the next day. Personally, I would wait a week at least. You should
      definitely discard the litter box and food/water bowls, or else
      clean both well with household detergents or a 1:32 bleach
      solution.
    _________________________________________________________________

PART II: If your cat has tested positive

  Some of these points are mentioned in the general section above, but
  here are more specific questions geared to people whose cats have
  tested positive. The most important point to stress is that FeLV+ cats
  *MUST* be made indoors-only. This needs to be done for two reasons.
  First, the more you expose your cat to outside ills, the more likely
  it is to contract an FeLV-related disease or infection. The second
  reason is that FeLV+ cats are like Typhoid-Marys to any other cat they
  meet. As noted above, the vaccine is only 75-85% effective, so any
  vaccinated cat that your cat encounters is at risk, as well as any
  unvaccinated cat. If these cats are then infected and they continue to
  interact and infect other cats, then you could give rise to an
  epidemic in your area. If you cannot or will not keep your FeLV+ cat
  indoors, than the only humane thing to do is find a home for it with
  someone who will (ways to do this are suggested below), or have your
  cat put to sleep. This may sound extreme, but it is extremely selfish
  to allow your cat to roam the neighborhood possibly infecting all the
  local outdoor cats just because you refuse to keep your cat indoors.
  Keeping your cat indoors is one of the responsibilities of owning an
  FeLV+ cat.

  My cat has tested positive. Should it be put to sleep?
  The mere fact of testing positive is not enough to merit putting a cat
      to sleep, although there may be other significant factors involved
      which do make putting the cat to sleep the best option. There are
      vets who recommend putting all FeLV+ cats to sleep. If your vet
      recommends this and you feel comfortable with that decision, then
      that is the best solution. Sometimes putting an FeLV+ cat to sleep
      is the best option for the cat, especially if it has acute
      symptoms and is in pain. This is never an easy decision and one
      which should not be taken lightly. If you do not feel you are
      capable of emotionally dealing with having an FeLV+ cat (or cannot
      keep the cat indoors), but do not want to put the cat to sleep,
      there are other alternatives which are discussed below. The one
      thing you should not do is ignore the virus. If your cat has
      tested positive, then you have a responsibility to take some
      action. FELINE LEUKEMIA VIRUS WILL NOT GO AWAY IF YOU JUST IGNORE
      IT!

  What will happen to my cat now that it has tested positive?
  Because there are so many different ways to respond to the presence of
      the virus, it is impossible to predict exactly what will happen
      (and when it will happen) to your cat. I've noticed that any 5
      vets you ask will give you 5 different answers to this question.
      The scientists who experiment and publish on the disease are also
      in disagreement. I have presented two different (published)
      viewpoints below. According to Hardy, et al (1980), (and these
      people seem to be the authorities on the disease) roughly half of
      all cats who test positive (and do not test negative again within
      a three month period) are persistently infected and show acute
      signs of FeLV-related diseases. The other half are latently
      infected and are in all other aspects 'healthy' although they are
      still carriers. 17% of all cats which test positive (and do not
      later test negative) will live past 4 years. The next point of
      view is taken from a much more recent article and has radically
      different statistics. According to Loar (1993), of cats which test
      positive for the disease only 5% will immediately become infected
      with an FeLV-related disease. The other 95% will enter the latent
      phase which will last for months to years. These 95% are still
      carriers for the disease and can infect other cats.

  Although my cat has tested positive, it is healthy in all other
  respects. How can I prevent an FeLV-related disease from becoming
  active in its system?
  There is no sure way to keep your cat healthy. Eventually, an
      FeLV-related disease will probably develop no matter what you do.
      However, one way in which a disease is likely to develop is if you
      stress your cat's system. If a cat's system is stressed, its body
      can't put as much energy into fighting off illnesses (just like
      you always seem to get sick during exams or when you have to make
      a presentation to your boss). "When all my cat does is eat and
      sleep 20 hours a day, how can it possibly be stressed?" you may
      ask. Anything which is upsetting or unpleasant for your cat may
      stress it, such as going for very long periods without food or
      water, overcrowding, movement to new territory, territorial
      conflicts, sending your cat to be boarded for long periods of
      time, or pregnancy and lactation. (Of course one should NEVER
      breed a FeLV+ queen as it will expose not only the tom, but all
      the kittens will be FeLV+. There is also an indication, although
      no proof, that FeLV causes abortions in queens. For the same
      reasons, neither should FeLV+ toms be bred.) Basically, keep in
      mind things which you have noticed in the past that seriously
      upset your cat. These are things which are more likely to lower
      your cat's natural immune system and give a disease the chance to
      attack.

  I have an FeLV+ kitten that I have decided to keep. Should I have it
  neutered/spayed?
  I've only encountered one case of a vet recommending not to spay a
      kitten because it was FeLV+. Unfortunately, going into repeated
      heat cycles was very stressful on her, and that owner believes it
      caused her to suffer ill effects of the disease sooner than she
      may have otherwise (of course there is no proof to this). It is
      true that there is a small added risk to anesthetizing an FeLV+
      cat, but that risk will well worth the alternatives. Especially
      since a whole cat will have a very strong desire to roam, thus
      further spreading the disease. In my personal experience, my vet
      did a very careful screening to make sure my FeLV+ cat could
      handle the anesthesia before operating. It really should not be
      much of a problem, but always make sure if your cat needs surgery
      that you remind the vet and staff that your cat is FeLV+.

  Should I continue to vaccinate my cat if it is FeLV+?
  The literature recommends against continued FeLV vaccinations. Other
      feline vaccinations (panleukopenia, rabies, etc.) should be
      continued.

  I have had several cats for a long time. One of them recently tested
  positive, but the others have not. Do I need to get rid of the FeLV+
  one?
  This is a tough situation, for which there is no pat answer. You
      should discuss the matter with your vet. One vet I spoke with felt
      that chances are the other cats have already been exposed and it
      is probably best to just keep them up on their vaccinations and
      not change the household drastically. One study (Barlough, 1984)
      says that in a survey of 45 households from which FeLV+ cats were
      removed, 99.5% of the FeLV- cats remained negative. However
      households in which the FeLV+ cats were not removed had infection
      rates 40 times greater. It is probably best to remove the infected
      cat if it can be sent to a good home without causing too much
      disruption in your household, and your mental psyche.

  I have an FeLV+ cat and I want to find it a playmate. What should I
  do?
  There a few options. The only thing which you really ought NOT to do
      is get a healthy cat as a playmate or let your cat outside for
      excitement. Dogs cannot become infected with the Feline Leukemia
      Virus, and some dogs and cats, especially those raised together
      can be very close. One word of warning: getting a dog (or any pet)
      for the sole reason of keeping a cat company is not a good idea.
      If you consider getting a dog, make sure you understand the amount
      of time and responsibility that goes into caring for a dog (which
      is much more than that of a cat); otherwise you will regret the
      decision and both you and the dog will suffer. (There are
      excellent dog FAQs which will give you as much information on the
      matter as you can handle).
      Another option is getting a second FeLV+ cat. The obvious down
      side is that you not only have twice the vet bills, but you also
      put yourself at risk for twice the heart-ache when one or both
      become ill. However, if you are willing to take the risk you can
      search for FeLV+ cats by putting an ad in the newspaper and
      calling all your local vets and animal shelters and explaining
      your situation. They may put you on a list and should they receive
      any cats which test positive, they may give you a call. Make sure
      you give your current vet as a reference as most shelters and
      other vets will want to make sure you understand the
      responsibility of owning an FeLV+ cat or to make sure that you are
      not some psychopath looking for sick kitty-cats to do nasty things
      to (of course most people, especially your relatives, will think
      you are a psychopath anyway, for keeping and seeking out more
      FeLV+ cats).

  I have an FeLV+ cat that is otherwise healthy, I do not want to put it
  to sleep, but I can't keep it. What can I do?
  Similar to the above answer, place ads in the newspaper and contact
      your local shelters and vets and tell them you have an FeLV+ cat
      which you are willing to give to a good home. A good home is
      someone with another FeLV+ cat, or someone who does not have any
      other cats and will keep the cat indoors. Also, there are animal
      shelters which specifically take in FeLV+ cats. Again, contact
      your local vets and shelters to see if they are aware of any such
      haven to which you could send your cat. Almost all regular
      shelters will put to sleep any cat they receive which tests
      positive because the virus is so contagious. If you are going to
      do this, however, you should understand that is it unlikely that
      you will get instant results. If you expect to find a new home for
      an FeLV+ cat within a few days of making inquiries, you can pretty
      much forget it. Be prepared to hold on to the cat for a few weeks
      at least, while searching for a new home.
      One organization you may want to contact is the:
      MILLER-ROTH Animal Organization
      2000 E. Broadway #141
      Columbia, MO. 65201
      (573) 657-9633
      http://www.geocities.com/~miller-roth/felv.html
      They have a 4-page factsheet on how to go about finding a FeLV+
      cat a home that they will be happy to send it to anyone who sends
      them a business-sized self-addresed STAMPED envelope or contact
      them via email. Please contact them via email first, as this will
      save everyone time, postage and paper costs. If that is
      impossible, be sure to send them an SASE, as the extra expense of
      paying postage would be quite a drain on their already low funds.
      (Donations are always welcome, of course).
      If you choose to put an ad in the paper you MUST take the
      responsibility of making sure the people who express interest in
      your cat are doing so for legitimate reasons. You should interview
      them in person and check references if possible. There are people
      who will lie to get cats to feed to other pets, to sell to labs or
      to abuse. Think about this as you interview each potential
      candidate.
    _________________________________________________________________

References

    * CancerNet Factsheet is available via gopher to gopher.nih.gov
      following the menu path Health and Clinical Information/CancerNet
      Information/Fact Sheets from the NCI/Risk Factors and Possible
      Causes. Or you can call the Cancer Information Service toll free
      at 1-800-422-6237 (1-800-4-CANCER).
    * Hardy, William D., Essex, Myron, and McClelland, Alexander J.
      (eds). Feline Leukemia Virus. Elsevier/North-Holland, Inc. New
      York, 1980.
    * Loar, Andrew S. "Feline Leukemia Virus: immunization and
      prevention" in Veterinary Clinics of North America: Small Animal
      Practice. 23(1):193-211, 1993.
    * Barlough, J.E. "Seriodiagnostic aids and management practice for
      retrovirus and coronavirus infections" in Veterinary Clinics of
      North America: Small Animal Practice 14(5):955-969, 1984.
    * Olsen, R.G. et al "Oncogenic viruses of domestic animals: in
      Veterinary Clinics of North America: Small Animal Practice
      16(6):1129-1144, 1986.

 Additional Readings

    * Hardy, W.D. Jr, et al. "Biology for Feline Leukemia Virus in the
      natural environment" in Cancer Res. 36:582, 1976.
    * McClleland, A.J. et al. "Prognosis of healthy Feline Leukemia
      Virus infected cats" in Rev. Cancer Res. 4:121, 1980.
    * Rojko, J.L., and Hardy, W.D. Jr. "Feline Leukemia Virus and other
      retroviruses" in The Cat: Diseases and Clinical Management, NY:
      Churchill Livingston, 1989.
    * Rojko J.L. et al. "Reactiviation of latent Feline Leukemia Virus
      infection" in Nature (Lond.) 198:385, 1982.
    * Also, the Journal of the Am. Vet. Med. Association, 199(10), Nov.
      15, 1991 is devoted entirely to feline viral diseases.
    _________________________________________________________________

  This article is Copyright (c) 1995 by [ [email protected]]
  All rights reserved, please ask about redistribution.
  This URL is: http://www.dgsys.com/~ermiller/FeLV.html
    _________________________________________________________________

Other FeLV sites of interest

  http://web.vet.cornell.edu/public/fhc/felv.htm, from the Cornell
  Feline Health Center
  http://www.angelfire.com/il/felv Newer Methods For Treating FeLV+ Cats
  (make sure you discuss these options with your vet)
  http://www.geocities.com/Heartland/Ranch/6167/ FeLV support site
    _________________________________________________________________