Bovine Tuberculosis and Wildlife – Fact Sheet
Are wild animals susceptible to bovine tuberculosis?
Yes, bovine tuberculosis (TB) is a chronic infectious bacterial disease, caused by Mycobacterium bovis (M. bovis) that affects a wide range of mammals, including wildlife, livestock, and humans.
Is bovine tuberculosis common in wild animals?
In some parts of the world where bovine TB has persisted as a wildlife reservoir of infection the disease has been transmitted to livestock, and thwarted efforts to eradicate the disease from farm animal populations. Examples include the European badger in the United Kingdom and Ireland, the brushtail possum in New Zealand, wild boar in Spain. Although surveillance activities indicate that infection of wildlife is not common in North America, bovine TB has become established in elk, white-tailed deer and bison in specific geographic areas.
In Canada, there are two wildlife populations known to be infected with bovine TB: the wood bison of northern Alberta and the adjacent Northwest Territories in and around Wood Buffalo National Park and the elk and deer of southwestern Manitoba in and around Riding Mountain National Park.
Can wild animals transmit bovine tuberculosis to other wildlife and livestock?
Although many wildlife species are susceptible to infection with the bacteria, most wildlife species are not believed to be able to maintain the disease in the population in the absence of infection from another species (e.g. infected livestock) or a change in population or behaviour that enhances disease spread. In Canada, only the infected elk and deer of southwestern Manitoba are believed to have been responsible for transmission of disease to cattle around Riding Mountain National Park.
What does CFIA do to control bovine tuberculosis in wild animal population?
Responsibility for controlling disease rests with the agency that has legal jurisdiction over wildlife species. Animals within national parks are a Parks Canada Agency responsibility. Animals that are free roaming or on provincial crown land, are a provincial responsibility. Although the CFIA does not have a program specifically designed to control disease in wildlife populations it can provide information, advice, scientific and laboratory support to agencies which have jurisdiction over wild populations.
How is bovine tuberculosis controlled in a wild animal population?
The problem of bovine TB in wildlife is complex as there are limitations to what can practically be achieved and a variety of stakeholder interests that need to be taken into consideration. A range of options to address the disease risk have been adopted in various jurisdictions (some practiced in Canada) including:
- Wildlife population reduction or depopulation and replacement (with disease-free animals)
- Effective on-farm biosecurity to protect livestock and feed from contact with wildlife
- Measures to prevent baiting and certain wildlife herding behaviours
- Continued participation in surveillance and testing efforts to protect livestock from potentially diseased wildlife
- Vaccination of wildlife to reduce transmissibility to livestock
- Wildlife-free buffer areas to prevent contact between wildlife and livestock
The particular set of measures applied varies between jurisdictions depending on the particular wildlife reservoir species, population density, and wildlife management regime.
Can humans contract bovine tuberculosis from field-dressing and eating the meat of an infected wild animal?
Although bovine TB does not readily transfer to humans, anyone handling and consuming meat from an infected animal is at risk of contracting the disease. Anyone who hunts bison in the vicinity of Wood Buffalo National Park or elk and deer around Riding Mountain National Park should inform themselves concerning disease symptoms. It is recommended that hunters practice biosecurity measures , including wearing plastic gloves and staying upwind when handling potentially infected wildlife and washing hands, knives and clothes in warm soapy water after field dressing an animal. Ensure that meat is well cooked. Hunters that suspect their kill is infected should contact their provincial or federal agencies and seek medical advice if they suspect they may have been exposed.
What does CFIA do when domestic cattle have been exposed to wild animals with the disease?
As a precautionary measure, cattle, bison, elk and deer are tested for bovine TB. If livestock has a positive reaction to the test, they are ordered destroyed and tissues are collected for laboratory examination. Refer to What to do if your farm is investigated for more information activities following a positive test result.
Why are domestic animals infected with, or exposed to, bovine tuberculosis destroyed?
Canada follows a strict testing and eradication program in domestic animals. Because tuberculosis may have a long incubation period and does not always show up in tests, regulations require that all infected animals as well as all exposed susceptible animals be destroyed.
Provincial Wildlife Programs
- Alberta Agriculture and Resource Development – PDF (99.8 kb)
- Manitoba Conservation and Water Stewardship
- Date modified: