Feline Infectious Anemia (Hemobartonellosis)

Overview of Feline Infectious Anemia

Feline infectious anemia, also known as hemobartonellosis or feline hemotropic mycoplasmosis, is a parasitic disease of worldwide significance. Affected cats experience some degree of anemia is a parasitic disease of worldwide significance. Affected cats experience some degree of anemia, although it also causes a wide range of other clinical signs that can vary from simple depression and lethargy to fever and shock.

Below is an overview of feline infectious anemia followed by in-depth information about the diagnosis and treatment options for this disease.

The causative organisms for this disease are Mycoplasma haemofilis previously called Hemobartonella felis large form and Mycoplasma haemominutum previously called Haemobartonella felis small form. They are parasites that affects the outer surface of feline red blood cells. The name of the parasite was changed after extensive study when it was determined that the parasite was genetically similar to other mycoplasma organisms.

Cats of all ages and breeds can be affected. There are several predisposing risk factors for feline hemotropic mycoplasmosis, including the presence of another disease that causes immunosuppression such as cancer or feline leukemia virus (FeLV), deficient vaccination status, history of cat bite abscesses within prior few weeks and cats that have exposure to fleas and ticks. Young intact male cats are at increased risk due to fighting and roaming behaviors.

The primary mode of transmission is by blood sucking arthropods such as fleas, ticks and possibly mosquitoes.

The impact of the disease varies widely. Some cases are mild, while other cases can be associated with severe weakness, depression anorexia, fever, weight loss, anemia, and sometimes death.

What to Watch For

Diagnosis of Feline Infectious Anemia

Treatment of Feline Infectious Anemia

Home Care and Prevention

Carefully monitor your cat during treatment. Administer medications as prescribed and notify your veterinarian if you are having trouble giving the medication. Recheck appointments are very important to make sure your cat continues to improve.

Keeping your cat indoors can help prevent exposure to possible vectors of infection, reduced fighting between cats and reduced exposure to various diseases and viruses. Neuter outside cats to reduce the risk of cat fights. Use medications to prevent fleas and ticks.

In-depth Information about Feline Infectious Anemia

Feline hemotropic mycoplasmosis is an infectious disease caused by the parasite Mycoplasma haemofelis. It causes hemolytic anemia, a type of anemia where the body destroys its own red blood cells because they “look different” to the immune system. The disease was first described in the United States in 1953.

The causative agent, Mycoplasma haemofelis, is a parasite that affects the surface of feline red blood cells. A large study performed in 1990 helped establish the prevalence of Mycoplasma haemofelis in the general cat population and identify risk factors. The prevalence of feline hemotropic mycoplasmosis was determined to be 4.9 percent in all cats. As might be expected, in healthy cats the prevalence is a bit lower (3.6 percent), while in sick cats, it’s a bit higher (7.5 percent). The true prevalence of the disease may be underestimated because of the difficulty diagnosing the disorder.

Factors identified as increasing the estimated risk for hemotropic mycoplasmosis were:

The mode of transmission in naturally occurring infection has been difficult to elucidate fully. It is believed that hemotropic mycoplasmosis is transmitted by insect vectors, such as fleas, ticks, and mosquitoes, direct contact between cats such as with bite wounds and via blood transfusions. Transmission in utero or by breast milk has been suggested by the detection of the organism soon after birth; intrauterine transmission was suspected when kittens from an infected queen were found to be infected three hours after birth. There are no known risks to humans.

Cats with hemotropic mycoplasmosis experience four phases of disease.

Clinical signs and physical exam findings of Mycoplasma haemofelis infection are similar to that seen with other anemias; the severity of the clinical symptoms is related to the magnitude of the anemia, and how quickly that degree of anemia was reached. Pale (possibly yellow tinged) mucous membranes, fever, fatigue, depression, tachypnea (rapid respiratory rate), tachycardia (rapid heart rate), decreased appetite, and enlarged liver and spleen are some of the symptoms that may be observed in cats with hemotropic mycoplasmosis.

In-depth Information about Diagnosis of Feline Infectious Anemia

Definitive diagnosis of hemotropic mycoplasmosis requires the demonstration of the organism on the patient’s red blood cells. Other tests are performed to help assess the general health of the patient and help characterize any secondary conditions that might have led to the disorder, and to evaluate the effects that the disease is currently exerting on the patient.

Cats infected with hemotropic mycoplasmosis experience phases where the parasite is present in the bloodstream (parasitemic phase), alternating with phases where no organism is present (non-parasitemic phase). A negative test may not necessarily mean that the organism is not present; it may just mean that the blood has been sampled during one of the “non-parasitemic” phase. Daily sampling may be necessary for a few days before organisms are found in some cats.

In-depth Information about Treatment of Feline Infectious Anemia

Prognosis for Feline Infectious Anemia

The prognosis depends on the severity of the disease and response to treatment. The prognosis is generally considered good when treated aggressively with antibiotics, blood transfusions if needed and additional supportive care.

Home Care for Feline Infectious Anemia

Optimal treatment for your pet requires a combination of home and professional veterinary care. Follow-up can be critical, especially if your pet does not rapidly improve. Administer all prescribed medication as directed and alert your veterinarian if you are experiencing problems treating your pet.

Have your cat re-examined according to a schedule set by your veterinarian, to make sure that the red blood cell count is rising and the anemia is resolving.

The prognosis for recovery is good when hemotropic mycoplasmosis occurs as a primary problem; up to 75 percent survive the episode if a definitive diagnosis is made and therapy is instituted. Even without treatment, about 65 percent of acutely ill cats will survive. Recovered cats become carriers for an unknown duration of time, possibly throughout life. Prior exposure does not induce immunity, and recurrence of disease is theoretically possible, although this rarely happens.

The prognosis is worse if Mycoplasma haemofelis is an opportunist, especially if the primary disorder is FeLV. If the feline leukemia virus has already affected the bone marrow, treatment is usually unrewarding; blood transfusions plus antibiotic therapy does not induce long-term remission.