Researchers develop faster, cheaper test for TB

The bacteria infection that causes tuberculosis is the deadliest of any infectious disease in the world, causing three deaths per minute, said Jordi Torrelles, one of the research program’s co-leaders. “But tuberculosis can almost always be treated and cured with the right medications, so we wanted to find a way to get patient results more quickly.”

Researchers began working on the test in 2017 and developed a simple method to test mucous samples by decontaminating them with a salt mixture and placing portions of it on a plate with 12 separate wells – one contains the sample alone, and 11 contain the sample and a drug used to fight the infection. If the bacteria grow back in the well with no drugs, the person is infected with tuberculosis; if the bacteria grow back in any well containing drugs, they are infected with a drug-resistant strain.

Designed with low-income communities and rural limitations in mind, the $7.20 test does not require a hospital or lab analysis, can be completed by anyone, and yields results in as few as 13 days, Torrelles said. By comparison, some tests for the disease cost more than $600 and can take up to 86 days to produce results.

“We wanted to come up with a very cheap way to provide a test for tuberculosis to low-income areas where there are no community resources to do it,” Torrelles said. “In the continental U.S. it doesn’t take long to get your results, but if you are in a rural setting, like the Democratic Republic of Congo, it will take from two to six weeks to get to the hospital, then you have to have a complete workup, and then continue to be monitored to determine if the prescribed drugs are working.”

In the U.S. and other developed countries, molecular diagnostic tests for tuberculosis provide results within several days, but the technology needed to complete them cost thousands of dollars. “We want to provide solutions for communities that cannot afford [these devices] and where rates of tuberculosis are increasing,” Torrelles said.

Tuberculosis is one of the world’s deadliest diseases, killing 1.3 million people in 2017, according to the Centers for Disease Control and Prevention. It’s more of a problem in developing countries than in the U.S.; of the 10 million people around the world diagnosed with tuberculosis, just 9,105 cases were reported in the U.S.

In addition to being potentially fatal, the disease is expensive and time-consuming to treat, according to  the CDC. Depending on whether the strain is drug-resistant or not, treatment costs range from $134,000 to $430,000, and the course of treatment takes anywhere from nine months to two years, depending on medication and regimen.

Research on the accuracy of the tuberculosis test developed in San Antonio began with 21 drug-resistant strains of tuberculosis provided by collaborators from the Mailman School of Public Health at Columbia University and the Public Health Research Institute.

The Texas Department of State Health Services also is partnering on the project, agreeing to test 100 samples at their infectious disease hospital, and provide the results to Torrelles and his team.

In November, researchers will collaborate with the Ministry of Health in the Democratic Republic of Congo – where more than 151,000 cases of tuberculosis were diagnosed in 2017 – to test 250 samples.

Torrelles said that if the test proves effective, he hopes to patent it to ensure the cost remains low, then convince the World Health Organization to adopt the test and utilize it in hard-hit areas around the world.

“My hope is that it will work well and improve treatment experiences,” he said. “Right now, someone can be treated for a long time before being able to identify if the drug is working, and the drugs are very expensive. We want to help and make an impact on that.”

Source: Rivard Report