TB blood tests are dangerous, WHO warns

The World Health Organization recently warned that tuberculosis blood tests are dangerous for patients because they are unreliable and often produce the wrong results.

The United Nations health agency announced that it will take the unprecedented step of issuing a recommendation against using such tests for TB, a lung disease that affects an approximate 14 million people worldwide. As many as a third of the world’s population is thought to harbor the bacteria that causes the active form of the disease, according to

"The tests are not reliable and a waste of money and time, putting proper care at risk," Mario Raviglione, the director of WHO's Stop TB department, said, reports.

A WHO review the tests showed that they produce a large number of false positives and negatives. Raviglione said he believes the tests are dangerous to patients because of their unreliability.

The WHO guidance that will be issued later in the week will be the first instance of the WHO issuing a “negative” policy that counsels against the use of a particular method for diagnosing a disease.

TB blood tests are commonly used in the developing world. The British medical journal the Lancet recently reported that some of the blood tests used in India are made in countries where such tests are not licensed.