Common Diseases of Lions: Viral, Bacterial, Parasitic, and Fungal

Lions (Panthera leo) in wild and captive settings face diverse infectious threats. Surveillance and preventive medicine are critical for conservation.

Viral Diseases

• Canine Distemper Virus (CDV): Morbillivirus. Respiratory, GI, neurologic signs (seizures, ataxia, myoclonus). High mortality. Outbreaks in Serengeti (1994, 2011) from domestic dogs. Vaccination (recombinant canarypox vector) used in captivity.
• Feline Immunodeficiency Virus (FIV): Lentivirus. Species-specific strains (FIV-Ple). Chronic immune depletion → secondary infections. Prevalence up to 90% in some wild populations. No effective vaccine.
• Feline Coronavirus / FIP: Rare but fatal.
• Rabies: Fatal encephalitis. Vaccination in captivity.

Bacterial Diseases

• Tuberculosis (Mycobacterium bovis): Zoonotic. Weight loss, cough, dyspnea, granulomatous lesions. Transmitted from buffalo, cattle, or humans. Diagnostic: trunk wash PCR, serology. Treatment impractical in wild.
• Brucellosis (Brucella spp.): Reproductive failure (abortion, stillbirth, infertility). Zoonotic. Serology screening.
• Anthrax (Bacillus anthracis): Acute septicemia, sudden death. Spores persist in soil. Outbreaks in dry seasons.
• Clostridial Diseases: Blackleg, tetanus, botulism.

Parasitic Diseases

• Intestinal Helminths: Hookworms (Ancylostoma), roundworms (Toxocara), tapeworms (Taenia). Diarrhea, weight loss, anemia.
• Ectoparasites: Ticks (vectors for Babesia, Theileria, Anaplasma, Ehrlichia), fleas, mange mites (Sarcoptes).
• Hepatozoonosis: Tick-borne protozoan. Muscle pain, atrophy.

Fungal Diseases

• Ringworm (Dermatophytosis): Microsporum, Trichophyton. Circular alopecic, scaly lesions. Zoonotic.
• Candidiasis: Mucosal/opportunistic. Oral, GI, urogenital.

Conservation Medicine Approach

Integrated health monitoring: non-invasive sampling (feces, hair, remote biopsy), telemetry, camera traps. Vaccination programs (CDV, rabies) in high-risk populations. Disease risk analysis for translocations. One Health collaboration with livestock/public health sectors.