- TORONTO (CP) -- Tuberculosis, once thought a disease of the past in Canada,
is growing increasingly resistant to the drugs used to treat it, suggests
a new Ontario government study.
- The analysis of TB cases over the last
10 years confirms what many scientists have been warning: there are more
and more instances where the infection doesn't respond to certain medication.
- A few people have died as a result.
- The "ominous" problem exists
mainly among immigrants from some countries in Africa and Asia, said Dr.
Frances Jamieson of Ontario's public health laboratories, the study's author.
- But drug-resistant strains could spread
if doctors and public health officials aren't vigilant about detecting
and aggressively treating cases, she said.
- "We must remain vigilant ... It's
not something we can ignore," said Jamieson.
- "If you don't do it, the risk of
spreading resistant tuberculosis is there."
- An outbreak such as occurred in New York
a few years ago could lead to "an escalating situation," she
- While Jamieson's study dealt with Ontario,
she said the problem also exists in other cities with large concentrations
of immigrants, such as Vancouver and Montreal.
- Experts at a conference on tuberculosis
in Toronto this week debated whether Immigration Canada's complex rules
allowing for some screening of the immigrants for TB need to be tightened,
- Jamieson's study looked at 6,655 TB patients
from 1987 to 1997 and their reaction to five different drugs.
- It found the proportion of cases resistant
to isoniazid, one of the most effective treatments, more than doubled to
12.9 per cent over that period.
- Resistance to another medication, streptomycin,
jumped to eight per cent in 1997 from five per cent in previous years.
- About 16 per cent of TB cases occurring
in Ontario are now resistant to at least one of the drugs commonly used
to treat the infection, she said.
- The usual treatment of the disease lasts
- Those with resistance to one or more
drugs must be treated with a blend of medication. It takes longer for those
people to be cured and the cocktail of pills can have unpleasant side effects,
- Resistance has built in certain poor
countries because patients go untreated, can afford only one drug or fail
to keep taking the pills until the disease is eradicated, said Jamieson.
- Others simply won't admit they have it,
- "TB has quite a stigma for a lot
of cultures so they don't want to say they have TB."
- Jamieson said similar problems exist
among Toronto's homeless population, where tuberculosis has been spreading
- Doctors can keep the problem in check
if they're sure to examine patients from high-risk countries for TB, and
prescribe the appropriate treatment, she said.