WHO: Blood tests for tuberculosis are unreliable

July 18, 2011 By FRANK JORDANS , Associated Press

(AP) -- Widely used blood tests to detect tuberculosis are "dangerous" to patients because they are unreliable and can produce wrong results, the World Health Organization warned Sunday.

The U.N. health agency said it will issue an unprecedented recommendation against using such tests for the infectious that affects some 14 million people worldwide. As much as a third of the world's population is thought to harbor the bacteria that causes TB.

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

A review of the tests has shown that they produce too many false negative and false positive, according to WHO.

Raviglione told The Associated Press that the blood tests "are in fact dangerous to patients, since some cases will not be detected and some will be called TB when in fact they do not have it,"

The WHO guidance will be issued later this week. It is the first time that WHO has issued a "negative" policy, specifically counseling against the use of a particular method for diagnosing a disease.

The use of TB blood tests is particularly common in such as India, where an estimated 3 million people are infected with the disease.

The Lancet medical journal reported in January that some of the kits used there are made in where such tests aren't licensed. They are ordered by doctors who receive greater commissions for the blood tests than for the older and more reliable sputum microscopy method, the journal reported.

"Many of these tests are used in the private-for-profit sector, charging poor people who do not understand the lack of value of the test," Raviglione said.

Explore further: TB test offers patients quicker and easier diagnosis

shares

Related Stories

New TB test reveals patients at risk, says study

October 20, 2008

A recently introduced blood test can reveal which patients may develop active tuberculosis (TB) much more precisely than the 100-year old TB skin test, according to a new study published today in the journal Annals of Internal ...

Taiwan scientist unveils rapid, low-cost TB test kit

March 28, 2010

A Taiwan scientist on Sunday unveiled what he said is the first low-cost and efficient test kit for identifying tuberculosis bacteria, killer of more than 1.5 million people worldwide every year.

South Africa to test all HIV patients for TB

October 13, 2010

(AP) -- Health officials in South Africa said Wednesday they recommend screening all HIV patients for tuberculosis and want automatic TB tests for HIV patients to become normal procedure within five years.

Recommended for you

Zika virus may persist in the vagina days after infection

August 25, 2016

The Zika virus reproduces in the vaginal tissue of pregnant mice several days after infection, according to a study by Yale researchers. From the genitals, the virus spreads and infects the fetal brain, impairing fetal development. ...

In sub-Saharan Africa, cancer can be an infectious disease

August 26, 2016

In 1963, Irish surgeon Denis Parson Burkitt airmailed samples of an unusual jaw tumor found in Ugandan children to his colleague, Anthony Epstein, at Middlesex Hospital in London. Epstein, an expert in chicken viruses and ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

dogbert
not rated yet Jul 18, 2011
Good. We need to accurately diagnose and aggressively treat TB. Sham tests should be banned.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.