Tackling tuberculosis
Study shows two-hour bacterium DNA test saves weeks on diagnosis, treatment
Casey Lessard
Northern News Services
Monday, March 30, 2015
IQALUIT
For years, tuberculosis has infected Nunavut's health system, with the territory being one of the disease's safe havens in Canada.
But a study three years in the making has made Nunavut a leader at diagnosing and treating TB faster than anywhere in Canada.
And now the machine that made that possible is set to become the territory's key weapon in the fight against the disease.
GeneXpert MTB/RIF, a machine the size of a hard drive, allows laboratory technicians to amplify the DNA of a tuberculosis bacterium. Similar to how a photocopier causes a zoom effect through repeated enlargements, a polymerase chain reaction (PCR) amplifies DNA to the point it can be read for the presence of tuberculosis.
Dr. Gonzalvo Alvarez, a respirologist at Ottawa Hospital and an associate professor of medicine at University of Ottawa, is the lead for Taima TB, a partnership between his team, the Government of Nunavut, Nunavut Tunngavik Inc., and the medical team at Qikiqtani General Hospital. He credited the laboratory technicians there for the success.
"They were enthusiastic, learned how to do these tests, now run them with very good accuracy and showed that it was feasible in a place where there was no previous TB diagnostic facilities," Alvarez said.
The test takes about two hours to provide results, instead of the two weeks it can take in the south. Without GeneXpert, tests need to be done by looking at a culture under a microscope, typically in Ottawa or at a contracted medical facility.
"But now you have a lab-in-a-box," he said. "It's really a substantial advancement in TB diagnostics in that you can do this PBR test inside of a cartridge you can hold in your hand."
With a two-hour diagnosis, patients can start treatment the next day instead of waiting to hear back from a southern lab, which can take up to a month for those with lower levels of the bacteria.
This saves time not only for the patient, but lowers the chance the disease will spread to people the patient encounters. Faster treatment saves the health system money, and allows the patient to return to normalcy faster.
"We're very happy that the Government of Nunavut supported us right from the very beginning," Alvarez said. "That is reflective of their anticipatory move of saying 'We're going to earmark money for this', which is kind of rare (among governments)."
He expects a seamless transition from study to general operation, noting recent Government of Nunavut funding to continue the use of GeneXpert. Alvarez said the next step is determining whether the process is cost-effective.
There are nine million cases of active tuberculosis around the world every year, and 1.5 million die annually from the disease. Nunavut had more than 80 cases last year.
"Tuberculosis is a health problem that has been with us for far too long, especially here in Nunavut," then-Health Minister Leona Aglukkaq said at the launch of the study, funded by the Canadian Institutes of Health Research. She noted the Nunavut test would be used to set national guidelines for the test's use. "By making people more aware of TB and being able to diagnose it more quickly, we are taking important steps to fighting tuberculosis."
"What I do in my work is raise awareness throughout the country and beyond our borders that this is still a problem," Alvarez said. "The war on TB is not over."
