Bovine tuberculosis

What is it?

Bovine tuberculosis is a chronic infectious disease caused by bacteria that mainly affects cattle but can also infect humans and other animals. It develops slowly, often without visible signs for a long time, making it difficult to spot. It is a disease closely monitored in Tunisia because it represents a risk for public health and livestock.

Commonly observed signs

These signs are neither exhaustive nor specific. Only a veterinarian can establish a diagnosis.

Causes and risk factors

The disease is caused by a bacteria called Mycobacterium bovis, which belongs to the same family that causes human tuberculosis. This bacteria mainly settles in the lungs and lymph nodes of infected animals.

Farms with a high density of animals, frequent contact with wildlife or insufficient hygienic conditions present an increased risk. The introduction of uncontrolled animals into a herd and the absence of regular testing also favor the spread of the disease.

Transmission

Transmission occurs primarily through the respiratory route, when animals inhale contaminated droplets from an infected animal. It can also be transmitted by ingestion of contaminated raw milk, particularly from cows to calves. Humans can be contaminated by consuming unpasteurized milk or dairy products from infected animals.

Diagnosis and care

Diagnosis is the veterinarian's responsibility, based on clinical examination and laboratory tests. Care is decided case by case.

Prevention

References

WOAH — Organisation mondiale de la santé animale (ex-OIE)

OMS — Organisation mondiale de la santé

Content reviewed by the TunisieVet editorial team · Updated 18 August 2026