State officials confirmed yesterday that bovine tuberculosis has turned up in two northern Michigan cattle herds, one in Alpena County and another in Presque Isle County. The cases were detected during routine annual surveillance testing, and state veterinarians say both herds are now under quarantine while they carry out follow-up testing and track possible sources of infection.
State: Herds Identified During Annual Surveillance
According to the Michigan Department of Agriculture and Rural Development, the infected herds were found during whole-herd surveillance in areas where bovine TB has already been documented in free-ranging white-tailed deer. State Veterinarian Nora Wineland urged farmers to tighten on-farm biosecurity, saying, "The most effective way to prevent bovine TB from infecting cattle herds is to protect cattle from contact with wild deer and the disease they could be carrying." The agency said genetic analysis and an epidemiological investigation will be used to help pinpoint possible sources of the disease.
What Bovine TB Means for People and Animals
Bovine tuberculosis, caused by the bacterium Mycobacterium bovis, primarily affects cattle but can also infect other mammals and, in rare cases, humans. The Centers for Disease Control and Prevention notes that symptoms in people resemble those of other forms of tuberculosis, including cough, fever, night sweats and weight loss. Routine pasteurization of milk and federal meat inspection keep consumer risk low, officials say. Health authorities advise farmworkers, hunters and anyone else who may have been exposed to talk with their health care provider about testing if they develop compatible symptoms.
Investigation, Testing and Movement Rules
Michigan Department of Agriculture and Rural Development officials said the new detections follow a confirmed bovine TB case in a Charlevoix County dairy herd in February, which has already led to heightened surveillance in northern counties. While Presque Isle County is formally in the state’s Accredited Free Zone, it is subject to many of the same testing and movement requirements that apply in Michigan’s Modified Accredited Zone. Authorities said movement certificates, mandatory animal identification and possible test-and-removal programs will be used as needed to contain and limit any spread.
Hunters and Farmers Urged to Help With Surveillance
The Michigan Department of Natural Resources continues to ask hunters in northeastern counties to submit deer heads for bovine TB testing to help track the disease in wildlife. Agencies also plan outreach events for cattle producers in the region. State officials recommend straightforward biosecurity steps such as fencing, secure feed storage and limiting deer access to water sources to reduce contact between deer and cattle. Farmers with concerns are being directed to MDARD’s animal health staff, and anyone who believes they were exposed and later becomes ill is urged to seek medical attention.
Regulatory Impacts and Markets
The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service oversees national tuberculosis eradication rules and works with states on affected-herd responses. USDA APHIS warns that a prolonged outbreak can trigger stricter testing and movement restrictions that may ripple through the market by affecting the sale and transport of animals. For now, state and federal officials say there is no evidence that the inspected meat supply or pasteurized milk is unsafe.
State officials are encouraging producers to stay current on required testing and urging hunters to keep participating in surveillance programs as the investigation continues. MDARD’s April 6 release and local media will be updated as investigators learn more. CBS Detroit and local public radio have covered the announcement and shared agency contacts for people with specific questions.
