Although it might be thought of as a disease of the past, there were 1,700 people diagnosed with active tuberculosis in Canada in 2016.
Dr. Theresa Tam, the chief public health officer of Canada, wants to change that. She released a report Thursday focusing on the disease and calling for its elimination.
“I really feel that the timing is right, the timing is now to accelerate our TB elimination efforts,” she said.
Here’s a look at tuberculosis in Canada.
What is tuberculosis?
Tuberculosis is an infectious disease that primarily infects the lungs. “When someone gets TB, primarily they’ll develop a cough. They may develop blood in their sputum,” Tam said. They will likely lose weight and develop chills and a fever.
“TB can also go to your bones, affect your spine, affect your brain,” she said. “People who have TB in the brain may present with seizures, may present with meningitis. TB can affect your kidneys as well.”
How many Canadians have it?
Over 1,700 people were diagnosed with active tuberculosis in 2016. That number has held fairly steady over the last while, with roughly around 1,600 people diagnosed annually.
“We really plateaued after the 1980s,” Tam said. “We haven’t made any gains in the last several decades.”
National statistics only capture people who have active tuberculosis, not the likely larger number of people who have “latent” TB, meaning they don’t have symptoms and aren’t contagious, but still harbour the bacteria. These cases sometimes develop into active TB, but they mostly don’t.
Canada is doing well, though, by comparison to the rest of the world, where it’s the leading cause of death from an infectious disease. Nearly 1.7 million people died from TB in 2016, according to the World Health Organization. It’s “rare” for someone to die of TB in Canada, said Tam.
Who is affected?
Tam splits tuberculosis patients into two groups. The first group are Inuit, First Nations and Metis people – primarily those who live on-reserve or in remote communities. They account for roughly 20 per cent of cases.
“In that group, it’s the Inuit population that really has a much higher rate than non-indigenous Canadians – 300 per cent higher,” she said.
The second group is the foreign-born population, who account for roughly 70 per cent of cases. These are often people from countries that have high rates of TB. Although all individuals applying for permanent residency and certain people who apply for temporary residency are screened for active tuberculosis, some people carry the latent form of the disease. This might turn into active TB later, once they’re in Canada.
Areas in the Eastern Arctic, Newfoundland and Labrador, and the Prairies report higher rates of TB than other parts of Canada. Big cities, like Toronto, Vancouver and Montreal, where many immigrants settle, also see cases, said Tam.
What makes people susceptible?
Around 70 per cent of people who are exposed to infectious tuberculosis won’t actually get infected, according to the report. But certain factors make some people more likely to catch it, or to develop the active form if they already have the infection.
WATCH: Analyzing the risks of tuberculosis – Quebec’s public health department announced in 2016 that it was looking for passengers who were on an intercity bus because they may have been exposed to tuberculosis. We take a closer look at the disease.
“From a biological standpoint, anyone with a weakened immune system, if you have HIV, if you have diabetes, if you are a smoker, if you’re elderly, for example, you’re at higher risk of tuberculosis and its reactivation,” Tam said.
“Those who are living in poverty, crowded housing conditions, poor access to nutritious food for example, are at higher risk.”
If you’re living in a crowded home with an infected person, the prolonged contact could contribute to passing the infection to you, she said. Similarly, if you aren’t eating properly, this could affect your immune system and make you more susceptible.
These factors are all present in communities that have higher levels of TB, said Tam.
What can be done?
Tuberculosis is a treatable disease, said Tam, and can be cured. “It does take many months of a combination of antibiotics. So one of the challenges is making sure someone takes their medication and sustains that for a long period of time. So it is quite challenging. But it definitely is a curable disease.”
So – it can be eliminated, she said.
She thinks that targeting the “reservoir” of people who have latent TB, getting them tested and cured, would make a big difference. Increasing awareness and better screening programs will help with that.
Improving housing in communities where that’s a problem will also help.
She hopes that a concerted effort from the community to the international level will help to eliminate TB.
“Everything is possible if we focus on improving the underlying conditions that affect health. In doing so, we can make a realistic push to end TB in Canada once and for all,” says the report.