Michigan Department of Agriculture and Rural Development has confirmed bovine tuberculosis (TB) in a dairy herd in Charlevoix County. The location sits west of Michigan’s Modified Accredited Zone (MAZ), where the disease is known to circulate in wildlife.
The case was first detected during routine inspection at a federally inspected processing facility overseen by the United States Department of Agriculture Food Safety Inspection Service. An adult dairy cow tested positive. Officials traced the animal back to its herd of origin.
After that, the entire herd underwent testing. Additional infected animals were identified.
State officials say the detection highlights how difficult bovine TB can be to control. However, they also note that Michigan’s surveillance and traceability systems worked as designed.
“This latest detection highlights how challenging bovine TB can be to control,” said State Veterinarian Nora Wineland. “At the same time, it shows that our testing and traceability systems allow us to respond quickly and protect animal and public health.”
Wildlife Connection Remains a Concern
Bovine tuberculosis is a bacterial disease that affects cattle and other mammals, including humans. In Michigan, the disease remains established in free-ranging White-tailed deer in parts of the northeastern Lower Peninsula. Because deer and cattle can transmit the disease to one another, wildlife management plays an important role in control efforts.
The affected herd lies outside the MAZ. Within that zone, enhanced testing and movement requirements apply because of the known wildlife risk.
Investigation and Response
Animal health officials have launched an epidemiological investigation. They will examine how the herd became infected and whether other herds may be at risk. Traceback and trace-forward efforts are underway.
Within the MAZ, state and federal partners conduct routine surveillance testing. They also require official animal identification and enforce movement certificates. In addition, wildlife risk-reduction programs continue across the region.
Officials encourage producers to follow strong biosecurity practices. Limiting wildlife access to feed and water remains especially important. Maintaining accurate identification records also supports rapid response efforts.
While new herd detections are concerning, early identification remains critical. Swift action helps limit disease spread and protects Michigan’s livestock industry.
