Ghon's complex

A Ghon's complex retains viable bacteria, making them sources of long-term infection, which may reactivate and trigger secondary tuberculosis later in life.

[3] In countries where cow milk infected with Mycobacterium bovis has been eliminated (due to culling of infected cows and pasteurization), primary tuberculosis is usually caused by Mycobacterium tuberculosis and almost always begins in the lungs.

As sensitization develops, a 1 to 1.5 cm area of gray-white inflammation with consolidation emerges, known as the Ghon focus.

This combination of parenchymal lung lesion and nodal involvement is referred to as the Ghon complex.

[citation needed] In approximately 95% of cases, development of cell-mediated immunity controls the infection.