Which description correctly defines latent TB infection?

Which description correctly defines latent TB infection?

• A. The virus is active and contagious
• B. The virus is not active, no symptoms, cannot be spread
• C. It always causes fever
• D. It is always seen on chest X-ray

Answer: (B)

Latent TB infection means you are infected with Mycobacterium tuberculosis, but the bacteria are dormant. There are no symptoms and the person is not contagious because the infection is not active. A positive TB infection test (like a TB skin test or IGRA) may be present, but a chest X‑ray is usually normal and sputum tests are not positive. Fever and other symptoms are not part of latent infection. This differs from active TB, where symptoms such as cough, fever, night sweats, and weight loss occur and the person can spread the bacteria to others. The incorrect statements treat TB as a virus, imply fever always, or require an abnormal chest X‑ray, none of which fit latent TB infection.

Latent TB infection means you are infected with Mycobacterium tuberculosis, but the bacteria are dormant. There are no symptoms and the person is not contagious because the infection is not active. A positive TB infection test (like a TB skin test or IGRA) may be present, but a chest X‑ray is usually normal and sputum tests are not positive. Fever and other symptoms are not part of latent infection. This differs from active TB, where symptoms such as cough, fever, night sweats, and weight loss occur and the person can spread the bacteria to others. The incorrect statements treat TB as a virus, imply fever always, or require an abnormal chest X‑ray, none of which fit latent TB infection.