No one likes to see a beloved pet scratching away at their fur and skin. But if you think fleas are just a nuisance, think again. These pests can actually cause a number of diseases in cats and dogs—and transmit some of those diseases to people.
Fleas can cause a lot of serious diseases and suffering. Like ticks, fleas cause harm through parasites that they carry, transmitted through bites or other routes. Flea saliva itself can even cause problems in both dogs and cats. Here are 6 flea-related diseases in cats and dogs that all pet parents should know about.
Tapeworms
What it is: One of the grossest, most easily noticed diseases in dogs and cats, tapeworms are contagious to dogs, cats and humans, and are transmitted via the lowly flea. In order to become infected with this flea disease, dogs, cats or humans must ingest a flea that is infected with tapeworm larvae. Cats and dogs usually ingest these fleas while grooming; less commonly, humans become infested by ingesting a flea by accident. Tapeworm larvae hatch from the infected flea, attach themselves to the intestine, feed off the host and reproduce. Tapeworms are usually noticed when they release egg packets called proglottids that leave the body via the pet’s anus, and look like little grains of rice.
Symptoms
- Tapeworm segments (proglottids) noticed around the pet’s anus or in their poop
- Weight loss and dull haircoat in severe infestations
Treatment
Tapeworms are eliminated by administering a prescription medication. It comes in oral and injectable forms. For cats there is a topical preparation.
Flea Allergy Dermatitis
What it is: FAD for short, flea allergy dermatitis is an intensely itchy skin disease due to an allergy to flea bites. Afflicted dogs and cats can be so itchy that they scratch their skin raw. Allergic pets can be so sensitive that the bite of just one flea can cause intense itching and scratching for a week!
Symptoms
- In dogs, FAD usually manifests as itchy hot spots either around the base of the tail or on the neck.
- In cats, FAD can manifest as itchy raw skin around the neck, or crusty bumps all over the body.
Treatment
Treatment of FAD consists of stopping the itching with an injectable or oral steroid medication or an allergy medication, treating any skin infections with antibiotics either orally, topically or both; and eliminating any fleas on all pets in the household, even the ones that aren’t allergic to flea bites.
Anemia
What it is: Puppies, kittens and very small adult dogs and cats can be so heavily infested with fleas that they become anemic, which means that they have a low blood count. Fleas are bloodsuckers, and small pets don’t have as much blood to give, putting heavily infested pets at risk for anemia.
Symptoms
- Lethargy and weakness
- Loss of appetite
- Pale gums
- Jaundiced skin or gums
Treatment
Most of the time, eliminating fleas is the first course of action. Severely affected pets may require a blood transfusion.
Feline Infectious Anemia
What it is: This disease is spread by fleas and can threaten your cat’s life. In this disease, parasites live and reproduce on a cat’s red blood cells, until the immune system recognizes the foreign invaders and launches an attack against the cat’s own red blood cells. This causes anemia via destruction of red blood cells. Cats become infected after being bitten by fleas infected by the parasite.
Symptoms
- Lethargy and weakness
- Loss of appetite
- Pale gums
- Jaundiced skin or gums
Treatment
Treatment for this disease requires antibiotics to kill the infective organisms. The immune system may need to be suppressed with immunosuppressive drugs to stop it from destroying red blood cells. Cats who are severely anemic may require a blood transfusion.
Cat Scratch Fever
What it is: Also called bartonellosis, is caused by a bacteria called Bartonella henselae that infects fleas. The fleas pass the bacteria in their feces. When cats scratch themselves, they can get infected by flea feces on their claws. If fleas are common and conditions are right, over 40 percent of cats in an area can become infected. Kittens are more susceptible. Cat scratch fever can also be transmitted to humans through scratches from cats with flea feces on their claws.
Symptoms
Most cats are asymptomatic, meaning they show no signs of the disease at all. But in some cases they do get sick and may show any of the following signs:
- Fever
- Swollen lymph nodes
- Red eyes
- Vomiting
- Low energy/hiding
- Loss of appetite
Treatment
Cat scratch fever is treated with antibiotics. Antibiotics must be given for a minimum of 4-6 weeks. However, no antibiotic has been established to completely clear the bacteria from the bloodstream. Because of concerns surrounding the extended treatment time and the possibility of antibiotic resistance, treatment for this flea disease in cats is only recommended in pets who have symptoms.
Murine Typhus
What it is: While rats are the main hosts of the flea species that carries Rickettsia typhi, the bacteria responsible for murine typhus, cats who come into contact with rodent hosts can carry the fleas and transmit the disease to humans. Fleas usually poop when they bite (gross, I know). Typhus is transmitted by flea feces infecting broken skin where a flea bites. This disease is rare in the United States, but it has been found in hot humid areas, mostly been reported in Texas and Southern California. While murine typhus does not affect cats, infected cats can carry the fleas that transmit the disease to humans, causing fever, body aches, nausea and more unpleasant symptoms in infected people.
Symptoms
No symptoms; cats simply carry infected fleas that are contagious to humans.
Prevention and Treatment
Treatment is aimed at eradicating flea infestations from your cat, and keeping fleas off your cat.
The bad news is this: Yes, fleas can cause disease in dogs and cats. But here’s the good news: All the flea diseases mentioned in this article require fleas to transmit, and fleas can be completely prevented with effective flea control. Talk with your veterinarian about the best flea control options for your pets.