Tularemia has many faces, depending on the species of infected animal, subspecies of infecting bacteria, and route of infection.
Rabbits, hares, and rodents
Clinical signs in rabbits, hares, and rodents have not been well described because affected animals most often have been found dead. Experimentally infected animals develop the following signs:
- Weakness
- Fever
- Skin ulcers
- Swollen lymph nodes
- Abscesses
Death usually follows in 8 to 14 days.
Sheep
Tularemia in sheep is typically a seasonal disease, coinciding with tick infestations.
Clinical signs include the following:
- Fever
- Rigid gait
- Diarrhea
- Frequent urination
- Weight loss
- Difficulty breathing
Affected sheep may isolate themselves from the remainder of the flock. Death is most common in young animals, and pregnant ewes may abort.
Horses
Reports of clinical disease in horses are limited, but the following signs have been described:
- Fever
- Difficulty breathing
- Incoordination
- Depression
Affected horses have had extensive tick infestation.
Cats
Disease in cats can range from no signs at all to severe illness, including blood infection that spreads to multiple organs. In cats that do develop signs, the following are common:
- High fever
- Lethargy
- Loss of appetite
- Swollen lymph nodes
- Enlarged liver
- Open sores in the mouth and on the tongue
- Abscesses
- Gastrointestinal signs like vomiting and diarrhea
- Respiratory signs like coughing, nasal discharge, and difficulty breathing
- Jaundice (yellowish skin or eyes) from liver involvement
Cats with blood infection can rapidly deteriorate and potentially die.
Dogs
Tularemia is rare in dogs, and dogs are less susceptible to becoming ill than other species. Clinical signs observed are related to mode of transmission and may include the following:
- Mild fever
- Lethargy
- Poor appetite
- Swollen lymph nodes
- Eye inflammation
- Runny nose or eyes
- Draining abscesses
In most cases, the disease in dogs is self-limiting and resolves with supportive treatment.