The number of people with Lyme disease in Nova Scotia could be as much as 30 times higher than government statistics show, says a new national peer-reviewed report co-authored by a Mount Allison University tick expert.
“We wanted to figure out the disconnect between what communities are seeing and what Public Health is saying,” said Vett Lloyd, who partnered on the study with Dr. Ralph Hawkins, a physician and clinical associate professor at the University of Calgary’s Cumming School of Medicine. “I think the immediate reaction might be one of anger and hostility within the public health community because one can take this as a criticism of Public Health and surprisingly that wasn’t the goal.”
The 22-page report, Under-Detection of Lyme Disease in Canada, published Monday in the journal Healthcare largely blames inadequate diagnosing for why only between three and four per cent of cases are being documented in Canada.
The study zeroed in on the common practise of diagnosing by blood testing, which has proven to be unreliable in detecting the presence of Borrelia burgdorferi — the bacteria carried by black-legged ticks that causes Lyme disease — particularly in the early stages of the illness. The same testing is being done in the U.S., but the United States Center for Disease Control and Prevention (CDC) has accounted for its limitation, and recently increased their estimates of the number of Lyme cases by approximately 10-fold. She says because blood testing is less accurate in Canada the presence of Lyme could be as much as 30 times higher than reported countrywide.
“The approach we took was not going out and testing a whole bunch of people. The data is already available. We looked at the data from American Public Health Service, the data published from Public Health Agency of Canada. We just reanalyzed that data as well as other peer reviewed scientific literature.
Dr. Strang, Nova Scotia’s chief medical officer of health, declined to comment on the report Thursday, saying his department would “review the findings in the report and get the perspective of Lyme disease experts at the Public Health Agency of Canada on it.”
Lloyd is expecting her findings to be challenged but insists the study will stand up to scrutiny.
“Any time you get something that’s new, the first thing that, in fact, everyone should do or say is, ‘Well, OK, is it valid? Does it connect with what I see?
“This is data that has been put out by the Public Health Agency of Canada, the CDC. It’s been published in peer review literature and you can’t really argue with that data.”
The study also looked at the number of dogs with Lyme disease infection to generate an estimate of the true number of Canadians suffering from this disease.
According to Public Health Agency of Canada statistics, 992 cases of Lyme disease were reported in the country in 2016, and about a third of them, 326, can be attributed to Nova Scotia.
The study says mandatory reporting in Canada underestimates the incidence and prevalence in a population and that no analysis to estimate the magnitude of under-detection in Canada has been undertaken.
Donna Lugar, director of the Nova Scotia branch of CanLyme, called the study’s findings shocking. But she said that she communicates with hundreds of Nova Scotians every year that claim to have the disease but go undiagnosed and untreated.
She says due to poor diagnostic techniques and treatment options, thousands of Canadians are needlessly suffering with the disease.
Vett said she was one of them. Five years ago she said she left Nova Scotia to get treatment for the disease after failing to get adequate care in the province.
“If we can at least agree on how many people are sick, we can start to evaluate how serious the problem is,” said Lloyd.
“I don’t think anyone is saying it’s not a serious problem but there hasn’t been recognition of how serious it is.”