The World Health Organization (WHO) has endorsed a new rapid test for tuberculosis (TB), Xpert® MTB/RIF test, which could provide an accurate diagnosis for many patients in just 100 minutes compared to current tests that can take up to six weeks.
The new test is built to run on Cepheid’s GeneXpert System which is already being used at a number of UK hospitals for detecting other infectious diseases, such as C. difficile and MRSA. One such hospital is The Yorkshire Clinic; the hospital is using Cepheid’s Xpert® MRSA Test to enhance MRSA screening of emergency patients. A handful of leading hospitals in the UK have already adopted the new TB test and are seeing the benefits it holds for their patients. It is likely that this announcement will spark a lot more interest in the technology, which far exceeds the current methodology.
The Health Protection Agency (HPA) recently reported that there were 9,040 new cases of active TB in the UK in 2009. England saw 8,286 new cases, 42 percent of which were identified in London alone due to higher levels of poverty, immigration, homelessness, imprisonment, HIV and drug abuse. In fact, last week, UK health minister Andrew Lansley asserted that immigration is a major factor in the UK’s 30-year TB rate high. The UK may be considered a low-burden country when it comes to TB, but these figures suggest that the nation should not take this recommendation lightly.
Currently, the most common testing method for TB is over 100 years old and is considered unreliable. It is known as the sputum microscopy test, or ‘smear test’, and relies on a human trained eye to look through a microscope and recognise the TB bacteria. According to the WHO, more than half of all active TB cases are missed through this method, but it allows for rapid detection of at least the most progressed cases. The problem is that the physician then sends another sample off to the lab for culture testing, where the organism is grown on a petri dish. Due to the slow growth nature of TB, it takes anywhere from two to six weeks for the result to come back during which point the patient has not been treated and the infection can easily have spread around the community.
This new technology accurately diagnoses patients within just two hours, knocking weeks off the waiting time. It enables hospitals to identify a significantly higher number of contagious patients during the initial testing phase and has the potential to save millions of lives across the globe.