What do fleas transmit to dogs? - briefly
Fleas serve as vectors for several canine pathogens, chiefly the tapeworm «Dipylidium caninum» and the bacterium «Bartonella henselae», which can cause tapeworm infection and febrile illness respectively. Additional agents such as «Rickettsia» spp. and various parasitic organisms may also be transmitted, contributing to skin irritation and systemic disease.
What do fleas transmit to dogs? - in detail
Fleas are vectors for several canine pathogens. The most significant agents transmitted directly or indirectly by adult fleas and their eggs include:
- Tapeworm (Canis tenuis): Flea larvae ingest tapeworm eggs; dogs become infected when they ingest infected fleas during grooming. Adult worms develop in the small intestine, producing segments that appear in feces or around the anal area.
- Bartonella henselae: Flea feces contain the bacteria; dogs acquire infection through skin abrasions or ingestion of contaminated material. The organism can cause fever, lymphadenopathy, and, in rare cases, endocarditis.
- Rickettsia species (e.g., Rickettsia typhi, Rickettsia rickettsii): Flea saliva may transmit these intracellular bacteria. Clinical signs range from fever and rash to severe systemic illness.
- Mycoplasma haemocanis and “Candidatus Mycoplasma haematoparvum”: Transmitted during blood meals, these organisms can cause hemolytic anemia, especially in immunocompromised or splenectomized dogs.
- Dipylidium caninum (dog tapeworm) is also spread when dogs ingest infected adult fleas; the life cycle completes within the flea’s body cavity.
Secondary effects of flea infestation, such as allergic dermatitis, can predispose dogs to secondary bacterial infections (e.g., Staphylococcus pseudintermedius) due to skin barrier disruption and scratching.
Diagnosis relies on fecal flotation for tapeworm segments, serology or PCR for Bartonella and Rickettsia, blood smears or PCR for Mycoplasma, and visual identification of adult fleas. Treatment includes anthelmintics for tapeworms, appropriate antibiotics for bacterial agents, and systemic ectoparasiticides to eradicate fleas and interrupt transmission cycles.
Prevention focuses on regular flea control using topical or oral insecticides, environmental decontamination, and routine veterinary screening for flea‑borne pathogens. Maintaining low flea populations reduces the risk of pathogen spread and associated clinical disease in dogs.