UC Davis Develops Blood Test to Pinpoint Infectious TB

New test can distinguish active TB from latent infection, enabling faster diagnosis and treatment to curb disease spread.

Mar. 24, 2026 at 7:38am

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Researchers at the UC Davis Department of Pathology and Laboratory Medicine have created a new tuberculosis blood test that can detect the active, infectious form of the disease. Unlike current TB screening tests, this new test can differentiate between active TB disease and a latent (inactive) infection, enabling faster diagnosis and treatment to help prevent the spread of tuberculosis.

Why it matters

Current TB tests cannot distinguish between active TB, which is contagious, and latent TB infection, which is not. This new blood test addresses a key shortcoming of existing diagnostics, allowing for more targeted treatment and control of the TB epidemic, especially in high-burden regions like India and other parts of South Asia.

The details

The new test measures the immune system's response to TB proteins, but specifically detects antibodies associated with active tuberculosis. This means a positive result identifies an active TB infection, unlike other tests that simply indicate exposure. The test was evaluated in a clinical trial in India from 2019-2023, where it performed well in detecting pulmonary TB as well as harder-to-diagnose cases in children and in other organs of the body.

  • The clinical trial of the new TB test was conducted in India from 2019 to 2023.
  • The researchers submitted data analysis and a clinical trial report to the Indian Council of Medical Research (ICMR) in 2026.

The players

UC Davis Department of Pathology and Laboratory Medicine

The research team at UC Davis that developed the new tuberculosis blood test.

Imran H. Khan

A professor in the UC Davis Department of Pathology and Laboratory Medicine who led the development of the new TB test.

AppGenex Diagnostics

A Bay Area startup co-founded by Imran H. Khan to commercialize the new TB test.

Indian Council of Medical Research (ICMR)

India's top institution for biomedical research, which will review the clinical trial data and potentially approve the new TB test for use in India and neighboring countries.

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What they’re saying

“If we can stop the spread of TB by more easily identifying active infections, we can make a significant difference in decreasing global numbers of this devastating disease.”

— Imran H. Khan, Professor, Department of Pathology and Laboratory Sciences

What’s next

If approved by the Indian Council of Medical Research (ICMR), the new TB test could expand to neighboring countries in South Asia, which account for a significant portion of the global TB burden.

The takeaway

This new blood test developed at UC Davis represents a significant advancement in tuberculosis diagnostics, as it can accurately distinguish active, infectious TB from latent infection. By enabling faster diagnosis and treatment of active cases, it has the potential to help curb the spread of this deadly disease, especially in high-burden regions.