Animals > Animal Diseases > Anaplasmosis  

Anaplasmosis

What is anaplasmosis?

Anaplasmosis, also called "Tick Fever," is a disease of domestic and wild ruminants, including cattle, sheep, goats and deer. The disease is caused by a microorganism that invades red blood cells. Anaplasmosis is a disease of major economic importance to the cattle industry in infected countries.

Do we have anaplasmosis in Canada ?

The Canadian Food Inspection Agency (CFIA) has concluded that anaplasmosis is currently not found in Canada, based on periodic surveys of the national cattle population. The disease occurs commonly in Africa, the Middle East, Asia, Australia, the United States, Central and South America and southern Europe. Anaplasmosis has been introduced into Canada several times by infected cattle imported from the U.S., but these outbreaks have been quickly eradicated.

The CFIA is continuing to verify Canada’s status for the disease through the testing of our national cattle herd and investigating any suspected occurrence of the disease.

Is there a human health risk associated with anaplasmosis?

There is no human health risk associated with this disease.

How is anaplasmosis transmitted and spread?

Anaplasmosis is transmitted through the blood of infected animals. The disease is most often spread by ticks that bite infected cattle, transferring the disease-causing microorganism from infected to susceptible animals. The disease can also be transmitted by biting flies or through contaminated instruments such as hypodermic syringes and dehorning equipment.

The major risk of introducing anaplasmosis to Canada is through the importation of infected livestock.

What are the clinical signs of this disease?

The severity of clinical signs varies considerably, depending on the species and age of the infected animal. Adult cattle, particularly those older than three years of age, are usually the most severely affected, with symptoms such as fever, anemia, weakness, respiratory distress, and, in some cases, death. Affected dairy cattle will have a rapid decline in milk production.

How is anaplasmosis diagnosed?

Preliminary detection is based on clinical signs and a history consistent with exposure to risk factors such as ticks and infected animals. Confirmation of a diagnosis is based on microscopic examination of blood and other laboratory diagnostic tests.

Are there any treatments for anaplasmosis?

Animals that show clinical signs of the disease have traditionally been treated with antibiotics. In severe cases involving valuable animals, blood transfusions and fluid therapy may be used as well. Recovery depends on the animal’s natural ability to produce new red blood cells. Younger animals generally have a greater rate of recovery. Cattle that survive anaplasmosis can carry the microorganism for life and become reservoirs for the disease, even after being treated with antibiotics. No treatment for anaplasmosis has been licensed for use in this country by Health Canada.

Vaccines to protect animals against anaplasmosis are commonly used in areas where the disease is endemic. In Canada, no vaccines are licenced for use, and vaccination is not part of the disease control strategy for anaplasmosis.

What is being done to control and prevent the entry and spread of anaplasmosis in Canada?

Anaplasmosis is a reportable disease in Canada under of the Health of Animals Act. This means that all confirmed or suspected cases must be reported to the CFIA.

Currently, cattle from countries or areas where the disease is known to exist are required to test negative for anaplasmosis before being imported into Canada. Since 1997, a certain class of feeder cattle known as "restricted feeders" have been imported without testing from some northern U.S. states during the winter period (October 1 to March 31) when the insects that spread the disease are absent. In lieu of testing, these animals are subject to insect control and antibiotic treatment. The CFIA is currently reviewing Canada’s import policies for U.S. feeder cattle.

Should anaplasmosis be diagnosed in Canadian cattle or bison, Canada’s current foreign animal disease strategy calls for its eradication through the testing of infected and exposed herds and the removal of infected animals.

How to get more information?

Contact your Canadian Food Inspection Agency Area Office:

You can find your local Canadian Food Inspection Agency District Office on the CFIA Web site or by consulting the blue pages of your local phone directory.