WHO backs pooled TB testing to expand diagnosis and cut costs

The World Health Organization issued new recommendations that experts say would help expand testing for tuberculosis while helping governments save money.

The recommendations include the use of near point-of-care molecular tests for diagnosing TB over smear microscopy, which checks for the presence of TB bacteria from an individual’s sputum sample using a microscope. While inexpensive, using smear microscopy can miss TB cases and can be time-consuming. WHO also recommends the use of tongue swabs in cases when individuals cannot produce sputum samples.

Another recommendation is the use of pooled testing for resource-constrained settings, where sputum samples from several individuals are mixed in one vial and tested together for TB. It requires no further testing if the pooled sample tests negative. However, if the test comes back positive, each sample needs to be retested individually.