Airborne spread of tuberculosis bacteria & Latent infection versus active illness

Airborne spread of tuberculosis bacteria

Mycobacterium tuberculosis usually affects lungs but can involve kidneys, spine, or brain. Active lung or throat disease releases germs into air during coughing, speaking, sneezing, or singing. Others can inhale them. Touching or sharing food is not the route described. Prolonged contact gives more opportunity for exposure. Transmission concerns breathing contaminated air, which explains why the site and activity of disease matter for spread. Latent infection means bacteria remain without causing symptoms, and the person cannot transmit TB.

Latent infection versus active illness

Latent infection means bacteria remain without causing symptoms, and the person cannot transmit TB. It can later become active, particularly when immune defenses weaken. Active disease involves multiplying bacteria causing illness. Treatment of latent infection reduces future progression risk. Feeling well therefore does not mean bacteria are absent, while infection evidence does not automatically establish active contagious lung disease. These distinctions guide further assessment and care.

Key concepts

Airborne spread of tuberculosis bacteria

Mycobacterium tuberculosis usually affects lungs but can involve kidneys, spine, or brain.

Latent infection versus active illness

Latent infection means bacteria remain without causing symptoms, and the person cannot transmit TB.

Symptoms and susceptibility

Active disease may cause fever, night sweats, weight loss, poor appetite, weakness, and fatigue.

Tests and completing treatment

Blood or skin tests show evidence of infection; chest imaging and sputum evaluation help distinguish active lung disease.

References

• MedlinePlus en español — Tuberculosis: Latent Infection and Active Disease