Q Fever in Cats

Q fever mainly affects pregnant females, resulting in weak newborns, stillbirths, and miscarriages. A feline that is not pregnant is not likely to become ill or show many signs of the bacterial infection. Q Fever can cause spleen enlargement, a decrease in energy and loss of appetite for a brief period of time. However, if a human contracts Q Fever after being exposed to their infected cat, the bacterium can cause severe health problem including endocarditis (inflammation of the heart valves), miscarriage, hepatitis, and pneumonia.

Q fever in cats is a bacterial zoonotic disease, meaning it can be passed on from feline to humans. Q fever, or query fever, is caused by the bacterium Coxiella burnetti, an organism commonly found around farm animals. Cattle, sheep, and goats are the main hosts of the Coxiella burnetti bacteria. However, felines often become infected due to inhalation, ingestion, or tick bite transmission of the bacterium. As livestock are the main hosts of the Q fever bacterium, the group of felines that are at highest risk are those that live on or near a farm or other livestock facility. 

The symptoms of Q Fever in cats are limited to:

• Splenomegaly (enlarged spleen)
• Lack of energy 
• Decreased appetite

Healthy felines that contract the Coxiella burnetti bacterium may display symptoms for several days, but return back to a normal state. The consequences for a pregnant female to contract the bacteria are much greater, resulting in weak or stillborn kittens and abortion, or miscarriage. A nursing female can also pass the bacteria to her offspring through milk, causing kittens to weaken further and disrupt the passing of immune antibodies. 

A feline can contract Q fever through the ingestion of a milk product or carcass of an infected animal. An aborted fetus, including the placenta and amniotic fluids, can harbor the Coxiella burnetti bacterium, therefore, coming into contact with birth material can also cause an infection. The Q Fever bacteria is also shed through the urine and feces of an infected animal. A cat can be infected by walking along the ground where an animal has eliminated and later licking her paws clean, posing a risk for feline infection. 

The Q fever bacterium Coxiella burnetti is a tough bacteria that can be passed through inhalation of the air in a contaminated area. External parasites, such as ticks, serve as a carrier for the Q fever bacteria as they go from ruminant to ruminant, feeding on their infected blood.

Diagnosing Q fever in cats is rather difficult, as the symptoms are limited, resemble the signs of other common feline illnesses, and often disappear over time. Your veterinarian will want to know your feline’s whereabouts and living environment. He or she may ask you if the feline has access to ruminant husbandry environments where the bacteria could have been contracted. Any symptoms that the feline is showing will be noted and a review of the feline’s medical history will be completed. The veterinarian may take a blood test to look at the feline’s immune system response. If antibodies has been made to fight the Coxiella bacterium, a feline likely has been infected. However, blood tests often prove inefficient in diagnosing Q fever and there is not currently a screening test for this infection. 

Pregnant females that have delivered stillborn kittens or those who have aborted their litter, have a higher chance of being properly diagnosed. A smear of cells that are taken from the fetus or placenta can be examined under the microscope to detect the presence of the Coxiella burnetti bacterium. 

The treatment of Q fever infection in cats is limited to antibiotics and tick preventatives. As not many felines display symptoms of a Q fever bacterial infection, there is not enough evidence to support the complete elimination of the Coxiella burnetti bacterium from the body. The veterinarian may treat the feline’s symptoms with supportive intravenous electrolyte infused fluids and medication to combat the enlarged spleen. If the feline’s appetite does not return to normal, the doctor may recommend a change in the feline’s diet or deliver food through force feeding to encourage weight gain. 

The symptoms associated with Q fever often diminish on their own or are eliminated with antibacterial drugs. Breeding females that have been previously diagnosed with Q fever will often have unsuccessful pregnancies in the future. The female may not carry the fetuses full-term or she may birth still fetuses. Talk to your veterinarian about your feline’s chances of having a successful pregnancy after a Q fever infection.