Health A-Z
Feline Immunodeficiency Virus (FIV)
Owner and veterinary guidance with linked treatments and source citations.
Feline Immunodeficiency Virus (FIV)
Species: Cat
Breeds Affected: All breeds (outdoor, fighting tomcats at highest risk)
Clinical review: Veterinary reviewer metadata is not available yet.
Guidance by audience
Use the global Pet owner/Vet toggle in the header. Each mode shows only what that audience needs.
For Pet Owners
Quick summary
A retrovirus (lentivirus) that attacks the immune system, analogous to HIV in humans. It is spread primarily by deep bite wounds. Infected cats may remain asymptomatic for months or years while the virus slowly weakens the immune system, eventually leading to feline AIDS. Track appetite, hydration, stool/urine changes, energy level, and symptom pattern over time.
Red flags
Call your vet today: Persistent or worsening symptoms. Emergency now: Collapse, severe breathing issues, seizures, uncontrolled bleeding, or severe pain.
What to expect at the vet
Diagnosis should combine history, exam findings, and condition-specific testing.
Prevention checklist
Reduce preventable risk through hygiene, vaccination/preventives when applicable, and routine veterinary follow-up.
For Veterinarians
Diagnostics
Diagnosis should combine history, exam findings, and condition-specific testing.
Differentials
Differential diagnosis considerations are not available yet.
Treatment considerations
No cure is available. Infected cats should be kept indoors and isolated from non-infected cats. Supportive care and prompt treatment of secondary infections are crucial (eg, dental care, antibiotics for gum infections, antiviral eye medications for herpes outbreaks). Good nutrition and stress reduction are important. In some cases, antiviral therapy (eg, zidovudine/AZT) is used to temporarily improve symptoms.
Follow-up strategy
Follow-up strategy is not available yet.
What To Do Now
Escalate care quickly if symptoms worsen, persist, or include emergency warning signs.
| Urgency | Signs | Action |
|---|---|---|
| Call your vet today | Persistent or worsening symptoms | Call your veterinarian the same day for guidance and exam scheduling. |
| Emergency now | Collapse, severe breathing issues, seizures, uncontrolled bleeding, or severe pain | Seek emergency veterinary care immediately. |
Prevention Checklist
Reduce preventable risk through hygiene, vaccination/preventives when applicable, and routine veterinary follow-up.
Treatments and Medication Links
Use these medication pages as a reference for options your veterinarian may discuss.
Detailed treatment strategy remains in the Vet view to avoid duplicate narrative blocks.
No linked medications are available yet.
Find a Vet Near YouFrequently Asked Questions
FAQ content is not available for this condition yet.
Data Sources
Last updated: February 16, 2026, 11:12 AM UTC
View source list
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Owner_summary · clinical_reference
https://www.merckvetmanual.com/searchresults?query=Feline+Immunodeficiency+Virus+%28FIV%29Reference search for condition background. -
Triage · clinical_reference
https://www.merckvetmanual.com/searchresults?query=Feline+Immunodeficiency+Virus+%28FIV%29Clinical triage framing. -
Vet_summary · clinical_reference
https://www.merckvetmanual.com/searchresults?query=Feline+Immunodeficiency+Virus+%28FIV%29Clinical workflow reference. -
Diagnosis · guideline
https://capcvet.org/?s=Feline+Immunodeficiency+Virus+%28FIV%29Guideline discovery link. -
Prevention · public_health
https://www.cdc.gov/search/?query=Feline+Immunodeficiency+Virus+%28FIV%29Public health discovery link. -
Treatment_overview · guideline
https://capcvet.org/?s=Feline+Immunodeficiency+Virus+%28FIV%29Treatment guideline discovery link.
Revision History
View revision log
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structured_enrichment2026-02-16 11:12 · etl
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structured_enrichment2026-02-16 11:00 · etl
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structured_enrichment2026-02-15 11:11 · etl
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structured_enrichment2026-02-15 11:00 · etl
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structured_enrichment2026-02-14 11:10 · etl
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structured_enrichment2026-02-14 11:00 · etl
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structured_enrichment2026-02-13 11:11 · etl
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structured_enrichment2026-02-13 11:00 · etl
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structured_enrichment2026-02-13 04:45 · etl
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structured_enrichment2026-02-12 22:47 · etl
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