1. Bovine TB Jackie Skelton, MPH, RN

2. Why bTB? Recent infection found in cattle on 2 farms in SW MI
Farms linked by sale of cattle
Cattle bought from Indiana farm
Genetically linked to 2016 bTB outbreak in IN
Human contacts tested on 1 farm
No human cases found
Still working to test contacts of 2nd farm
SW MI strain NOT related to known, ongoing deer herd infection in NW lower MI
6 states have current bTB activity
MI, NM,NE, SD, TX, IN

3. Background Organism: Mycobacterium bovis
Not M.Tuberculosis but clinically indistinguishable
Chronic, progressive disease
Can be deadly if disease not treated
Found in wild animals like deer, elk, bison
Passed from wild to domestic cattle through food/water sources/close contact
Can occur in the lungs, intestines, lymph nodes and other parts of the body
Infected animals often appear healthy
Routine testing of cattle has nearly eradicated infected cattle herds in the US
Less than 2% of human cases of disease are from M. bovis in U.S.
90% of cases in Mexico are M. Bovis

4. Transmission Animal to Human Person to Person
Consuming unpasteurized dairy products from infected animals
Direct contact with bacteria
Meat processing plants
Hunting/field dressing game
Transmission through air is thought to be rare
Person to Person
Same as M. Tuberculosis (airborne/droplets)
Coughing
Sneezing
Prolonged, close contact

5. Signs and Sypmtoms of M. bovis Disease
People
Animals
Very similar to M. tuberculosis
May be asymptomatic
Pulmonary Disease:
Fever/Night sweats
Weight loss
Cough
Depending on location of disease could also include:
Abdominal pain
Diarrhea
Swollen Lymph Nodes
May be asymptomatic
Localized infection ->Lymph nodes
Cough
Nasal discharges
Difficulty breathing
Emaciation
Intolerance to exercise

6. Testing Same tests for cattle and humans Skin test
IGRA (ie. Quantiferon Gold, T-Spot)
Approved for screening for M. bovis
Used on cattle prior to licensing for human testing
Testing usually stops after ‘mycobacterium’ identified, typing not done
Due to known bTB infected deer herd in NE lower peninsula, typing is done in MI

7. Treatment of M. bovis in People
Human cases treated the same as M. Tuberculosis cases
If strain is known to be M. Bovis
Disease treated with Ethambutol, Isoniazid, Rifampin
M. bovis resistant to Pyrazinamide
Latent infection treated with 9 months of Isoniazid
*No vaccine/treatment for animals.
*Herds infected with bTB are slaughtered and each animal tested

8. Control of M. bovis Treat latent/active disease in people
Educate public about risks
Federal programs started in early 1900s
Test livestock on farms
Monitor/test animals sent to slaughter
Track animals sold/moved across state lines
State level wildlife disease surveys and deer management strategies
Working with hunters

9. Thank You!
Resources:
Centers for Disease Control (2011). Division of Tuberculosis Elimination. Mycobacterium bovis (Bovine Tuberculosis) in Humans.
Michigan Department of Health and Human Services (2018). Michigan Emerging Disease Issues: