Weak Immune System in Cats
Weak Immune System in Cats - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Weak Immune System?
A weak immune system in cats, as well as other species, is caused by a deficiency in a type of white blood cell called phagocytes.  These phagocyte cells are an essential part of the immune system, as they engulf foreign invaders contaminating the blood, a process known in the veterinary world as phagocytosis. A deficiency in phagocytosis caused by an infection or an abnormally low number of phagocyte cells present at birth can cause a feline to become especially susceptible to infections of the gastrointestinal and respiratory systems and infections of the skin.
The immune system is your cat’s defense against parasites, viruses, and bacteria of the outside world. When this line of defense is weak or becomes weakened, a feline is more susceptible to developing life-threatening illnesses.
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Symptoms of Weak Immune System in Cats
A feline with a weak immune system is healthy overall for the first months of life, but as the feline stops nursing the supply of antibodies disappear and it becomes progressively susceptible to bodily infections. Noted symptoms of weakened immune system in cats include:
  • Continuously becoming ill 
  • Recurrent infections or infections that fail to respond to conventional treatment
  • Stunted growth
  • Anorexia
  • Lethargy
  • Poor hair coat
  • Symptoms related to the cause of weak immune system (feline parvovirus, feline leukemia virus or feline immunodeficiency virus)
  • Symptoms caused by a contracted infection (bacterial, viral or parasitical)
Causes of Weak Immune System in Cats
A weak immune system can either be a congenital disorder that the cat was born with or the immune system can become weakened due to conditions that are known to attack the infection fighting white blood cells, phagocytes. 
Congenital Weak Immune System in Cats
A cat born with an immunodeficiency disorder has an abnormally low number of phagocytes and will have difficulty fighting disease, leading to life-threatening situations. There is no cure for immunodeficiency disorder.
Viral Weak Immune System in Cats
Feline immunodeficiency virus (FIV)
Feline immunodeficiency virus attacks the immune system, causing low red and white blood cell counts. Spread from one feline to another through biting, the cat may not show signs of the infection for months or even years after contracting the virus. FIV infects a cat for life, leading to a deteriorated immune system. 
Feline leukemia virus (FeLV)
FeLV is a worldwide, retrovirus that despite use of vaccines, is still the number one cause of death among cats. FeLV severely suppresses the immune system, leading to conditions such as intestinal inflammation, reproductive disorders, immune-mediated disease, anemia and cancer. 
Feline parvovirus (FPV)
Parvovirus is a severe immune-depressing, viral infection that usually infects a feline short-term. Parvovirus attacks the lymphocytes and neutrophils portion of the white blood cell population, making a feline susceptible to bacterial and fungal infections. 
Diagnosis of Weak Immune System in Cats
The diagnosis of a weak immune system in your cat will begin with a review of your feline’s medical history. Your veterinarian will review his or her medical file, but any historical data you possess should be shared with the doctor to pinpoint when the problem began, symptoms, and possible causes. After the veterinarian exchanges notes with you, he or she may proceed to conduct the following:
  • A physical examination
  • Complete blood count (CBC): a test in which the number of blood cells in a single blood sample are counted to determine the total number of cells. 
  • Urinalysis: an examination of the urine. 
  • Biochemistry profile: a test that measures the components of blood, providing an overview of most bodily functions. 
Additional diagnostic testing may be completed based on the findings of previous tests. 
Treatment of Weak Immune System in Cats
Congenital weak immune system in cats has no treatment or cure, and viral associated weak immune system in cats is often not caught early enough to effectively treat the condition. Therefore, no effective treatment has been found to cure weak immune system in cats, but supportive care and prevention have been known to effectively lengthen a feline’s life. 
Your veterinarian may provide treatment for secondary conditions that comes with congenital and viral related weak immune system conditions. 
  • Antibiotics to fight bacterial infections
  • Antimicrobial medications to fight fungal/yeast infections
  • Chemotherapy 
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Recovery of Weak Immune System in Cats
The key to keeping your cat healthy when he or she has a weak immune system is prevention. Isolating your cat from other felines and animals, as well as preventing her from leaving the home is often the first rule of thumb when it comes to weak immune system management. Your veterinarian will advise you to be on the dot with vaccinations and may advise your cat to have additional vaccinations you may not usually ask for. As secondary infections are quite common in cats with depressed immune systems, you can expect your cat to visit the veterinarian often and go through various courses of prescribed medical treatment.
Veterinarians often advise breeders and owners of felines with known immune deficiency conditions to withhold from reproductive practices. Weak immune system conditions can be passed onto future generations if infected cats are allowed to breed. 
Weak Immune System Average Cost
From 584 quotes ranging from $200 - $3,000
Average Cost
$650
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Weak Immune System Questions and Advice from Veterinary Professionals
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Domestic cat (filipino cat
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dog-age-icon
Six years
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My pet has the following symptoms:
Severe Itching, Hair Loss, Wounds Cause By Itch In His Head, Ear, Nape, Shoulder And Armpit. Also He Is Meowning Too Much For Food
A month ago I noticed that he is itching so much, I googled it and the symptoms he is showing is perfectly fitted for the symptoms I read online. how can I solve this? Is there any chance that I can solve this without lending money? Plus, a week ago, he is meowing too much asking for food even though he just eaten a minute ago, I am giving him 2nd eat after he eat he will meow again asking for food. What can I do? is these can cause death? I am nervous that me unknowingly, he has problems in internal organs. I didn't have the opportunity to see a vet due to lack of money
July 27, 2020
Answered by Dr. Sara O. DVM
0 Recommendations
Hello, So sorry to hear that your cat is having issues. He may be itching due to allergies or other issues going on. Some cats as they start to get older will have issues with their thyroid and will eat a lot and lose weight. There is some over the counter allergy supplements you can try for your cat that you can pick up at your local pet store. Many times your cat may need to see the vet to feel better. I hope that your cat starts to feel better soon.
July 27, 2020
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Maine Coon
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Tiger
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3 Months
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5 found this helpful

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5 found this helpful

My pet has the following symptoms:
Vaccines
My kitten was given to me by the breeder before his second immunisation (I now know this should not have happened as this is a pedigree cat that should have remained with breeder for 13 weeks). I was unable to find a vet that offered the same brand of immunisation and so the advice was that I should restart his vaccines to ensure that he was fully protected. I’ve since been told by the breeder that this will have ‘ruined his immune system’ which I don’t believe to be true but has got me concerned. Should I be doing something to help him rebuild this? Have I really done any damage? I’m quite concerned as this is my first pet and I don’t want to get it wrong.
Aug. 17, 2018
Answered by Dr. Michele K. DVM
5 Recommendations
You have not ruined Tiger's immune system by vaccinating him. You have protected him against disease. If he is 12 weeks old, he will likely need a 3rd booster for FVRCP, which your veterinarian can safely give him.
Aug. 18, 2018
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tabby
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Opie
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7 Years
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0 found this helpful

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My pet has the following symptoms:
Lathargic Not Eating Or Drinking
I had a cat that died 2 weeks ago. I took her to the vet and they did blood work. They said mentioned something was attacking her white blood cells. They put her on fluids and antibiotics but nothing helped. We had to put her to sleep. Now I have another cat with the same systems. He's lethargic, not eating or drinking and his eyes are starting to look sunk in. What do I do. I spent everything I had trying to save the first one.
July 29, 2018
Answered by Dr. Michele K. DVM
0 Recommendations
Since I'm not sure what happened with your other cat, it is hard for me to comment on what might be going on with Opie, but since he was seen by your veterinarian, it would be reasonable to call them and ask what might be going on that would affect both cats, and see if there is any treatment that would help Opie.
July 29, 2018
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Tuxedo
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Rick
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9 Months
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My pet has the following symptoms:
Hoarse Meow
Soars On Lips
Soars On Paws
What’s wrong with my cat!?! I adopted two kittens in October and they had both been finishing meds for a kitty cold. A few days after adoption my cat Rick finished his meds and was okay until a month passed and he developed a rash on his paw that which was determined to come from “trauma” yet this same issue reoccurred three more times and varied in location (although all on his paws). Every time I’ve taken him to a vet they claim it’s trauma related but his last time the same rash began to occur I noticed it from the very start and there was no trauma. Due to this I switched the food to sensitive system and hypoallergenic litter in hopes of curing his issues. There has also been other small health issues. Twice he got bumps on his lips, the first time we determined it wa sbecause he was chewing on a basket which we removed from the house and then it healed but then another bump occurred on his lower lip right in the center. This bump on his lip and his most recent foot rash both occurred while he was taking antibiotics AND wearing a cone. He has basically lived in a cone for the last 6 months and I’m worried this is something more serious the vets seem to be passing over their heads. Now his meow has all of he sudden become lower and more hoarse than typical. It’s hard to tell if he’s feeling pain or discomfort because he’s an extremely happy kitty. Always talking and purring even when we are at the vet, this cat is like a child to me and the lack of concern expressed from the vets I’ve seeen have started to concern I may suddenly lose my cat over negligence.
May 31, 2018
0 Recommendations
Without examining Rick, it is difficult for me to say whether there is a cause for concern or not; traumatic injuries are common but there are other causes for skin lesions including self trauma, infections, parasites, allergies, autoimmune disease among other causes. The lump on the lip may be due to the use of a plastic food bowl, where small scratches irritate the lip causing a lump; however I cannot confirm this without an examination and discussion. It is bad you’re losing faith in your local Veterinarians, but you should visit again for an examination. Regards Dr Callum Turner DVM
June 1, 2018
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Turkish Angora
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Elsa
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1 Year
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3 found this helpful

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3 found this helpful

My pet has the following symptoms:
Sneezing
Lathargic
Eyes Watering
When my kitty Elsa came to live with me, shortly after she got a kitty cold. At the vet she got eye drops with antibiotics. I hoped the kitty colds weren’t a recurring thing that the vet said it might be. But when I took her on a flight for Christmas, she got a cold in FL. I got the same drops, but this one lasted a week so she got an antibiotic shot, she got better and that lasted for the flight back too. I recently took her to a friends house to live for 2 weeks while I was away on work. She got a small version of a cold and did not require vet assistance. This, however, gave the 3 other cats at my friend’s house kitty colds whom have never been sick. - does my cat get stressed with traveling or new environments? How can I help boost her immune system before traveling?
March 25, 2018
3 Recommendations
Stress is a big factor when looking at the immune system, but there is no hard and fast method of boosting a cat’s immune system although there are many products online which claim to do so; I have no specific scientific evidence from a reputable source to suggest any particular method. L-Lysine has anecdotally been used during respiratory tract infections, but again its efficacy is up for debate. Regards Dr Callum Turner DVM
March 25, 2018
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domestic short hair
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Aoife
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7 Months
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My pet has the following symptoms:
Shaking
Lethargy
Anorexia
Low White Blood Count
Self-Isolating
My cat Aoife fell off a balcony and was on mild pain killers for a weak. She got a bad flea infection; probably from spending the night in the animal hospital. Suddenly she stopped being her vocal self, responding to calls, and started hiding in cupboards and refusing to eat and hardly moving. She was isolated, would not eat or drink, and could hardly move/ interact with anything or anyone. The vets took full blood tests, tested her for leukemia, fed her vitamins through IVs, and had to give her fluids every day. Suddenly, a week later and right before we were going to admit her to a National Specialist Animal Hospital (though bloods revealed only low white count), she seemed to slowly bounce back to her normal self.
Weak Immune System Average Cost
From 584 quotes ranging from $200 - $3,000
Average Cost
$650
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