Canadians in several provinces face long lines for a swab to help diagnose COVID-19 as school and workplaces open. While new testing technologies could help, doctors say they won’t be a silver bullet.
The gold standard swab of the nose or throat can be uncomfortable. In contrast, a key promise of saliva tests is that people could collect saliva themselves so that fewer nurses and other health professionals would be needed at assessment centres, as staffing is one of the factors that can drive up wait times.
But that ideal won’t happen immediately. Currently in Canada, both saliva collection and testing remain a research project that regulators are closely evaluating.
There are three main barriers to overcome before saliva tests roll out widely.
Gobs of saliva vary in how fluid they can be, so collecting a high-quality sample can be a challenge even for something as non-invasive as spitting into a cup. The next hurdle for scientists is to get accurate and consistent results on the presence of the virus. Finally, clinicians need to determine how well the test results help them to correctly identify those with the disease.
Dr. Mel Krajden, medical director of the public health laboratory at the BC Centre for Disease Control, said health professionals face a quandary in finding the best ways to support a return to school, with all of its formative benefits for students, while protecting the oldest people at highest risk for severe consequences from COVID-19, such as grandparents or parents who are vulnerable because they have other health conditions.
Dr. Mel Krajden, medical director of the public health laboratory at the BC Centre for Disease Control. The Vancouver lab is exploring whether a saline gargle might work better than saliva testing itself. (Ben Nelms/CBC)
Krajden said in his experience, saliva testing works better with COVID-19 patients in hospital than on people living in the community who’ve tried it as part of a research project. His Vancouver lab is working on a simpler approach to collection than the traditional nasal swab using a saline gargle that seems to work in older children.
On Thursday, British Columbia announced it’s introducing a new mouth rinse, gargle and spit test for students from kindergarten to Grade 12 to make it easier for children and teenagers to check whether they have COVID-19. But this new test is only offered to school age kids, and only in B.C.
“What we need to be thinking through is what is the best mixture of tests and how are they best supplied?” Krajden said. “You want to have the right balance between convenience and sensitivity.”
Unresolved questions about saliva tests
Health Minister Patty Hajdu said on Wednesday that Health Canada will not approve a test that endangers Canadians’ health because they are inaccurate or offer a false sense of security.
In Canada, the mobile Spartan Cube was recalled because of reliability problems with its swab for the lab-in-a-box PCR test (also known as a polymerase chain reaction test) that was billed as providing results in less than an hour. In the United States, wide-scale problems early on with another PCR test developed by the Centers for Disease Control and Prevention hampered containment efforts.
A different technology, a molecular test launched by Illinois-based Abbott that the company says can deliver positive results in as little as five minutes, was also subject to a recall. It aims to detect the virus during active infection.
The outstanding questions about saliva tests include: How good an alternative could they be to a nasal or throat swab, who would benefit — such as different age groups or those who show symptoms — and when would they be available?
For governments and clinicians globally and across Canada, the challenge now is to organize all kinds of testing to allow society to function while preventing transmission to those at highest risk of severe consequences.
For the majority of young people, COVID-19 is like a common cold, Krajden said. It’s older adults and those who are vulnerable because of other health conditions that can face serious infection or death.
Policy-makers urged to shift gears
Dr. Larissa Matukas, head of the microbiology division at St. Michael’s Hospital, Unity Health Toronto, said experts and policy-makers need to shift gears to understand where cases are multiplying and shut them down quickly by moving resources, including testing, to where there are signs of concern.
“I’m not sure that’s actually happening right now,” Matukas said.
Dr. Larissa Matukas, head of the microbiology division at St. Michael’s Hospital, Unity Health Toronto, says experts need to understand where cases are multiplying and shut them down quickly by moving resources, including testing, to where there are signs of concern. (Yuri Markarov/Unity Health Toronto)
“We should be shifting to a very aggressive finding of individuals, testing those who are symptomatic or testing those who’ve been in close contact with those who’ve been diagnosed with COVID and then isolating those individuals to really stop all the chains of transmission,” she and her co-authors wrote in an editorial last week in CMAJ.
Matukas said the first step is finding cases by improving access to diagnostic nasal or throat swabs or having a health-care professional evaluate symptoms.
“Unfortunately, there’s been this drive, particularly in Ontario, to reach a particular number of tests per day indiscriminately of who is actually being tested,” she said.
Other, equally important parts of containment have been neglected, Matukas said, such as governments communicating a clear need for all people with symptoms compatible with COVID-19 to get tested immediately and to self-isolate while they wait for the test result.
Dr. David Williams, Ontario’s chief medical officer of health, said Thursday that people who haven’t been in contact with a case, aren’t connected to an outbreak, haven’t received a notification from the COVID Alert app and don’t have symptoms “might want to defer your visit” until the demand for tests falls.
Dr. David Williams, Ontario’s chief medical officer of health, said Thursday that people who haven’t been in contact with a case, aren’t connected to an outbreak, haven’t received a notification from the COVID Alert app and don’t have symptoms might want to delay testing until the demand falls. (Government of Ontario)
‘New technologies are always welcomed’
The level of disease in a particular community also makes a difference in misdiagnosing COVID-19 — another accuracy wrinkle to overcome in adopting quick, at-home saliva-based antigen tests for use in Canada.
“All new technologies are always welcomed,” Matukas said. “They always need to be evaluated in an objective, independent evaluation, and that’s the purpose of not just Health Canada, but that’s my job.”
As a medical microbiologist, Matukas carefully evaluates every diagnostic test introduced to ensure it meets the performance characteristics patients need in hospital. As part of her evaluation, new technologies are compared with a standard way of testing as a reference.
Lab workers need to do the same quality-assurance steps to check tests and equipment from all manufacturers. The goal is to ensure they perform well under real-life conditions, not just optimal ones.
Antigen tests that are used to identify mid-infection as the microbe multiplies, such as rapid tests for strep throat, is another technology under evaluation to help detect people likely infected with COVID-19 in schools, long-term care homes or other high-risk environments.
A laboratory worker shows a prototype of a self-test that will use saliva in a rapid COVID-19 test, which could replace more commonly used swabs, at the University of Liege, Belgium, in August. In Canada, saliva tools are also still being researched. (Yves Herman/Reuters)
Krajden, of the BCCDC, said more data is needed to determine when it makes sense to deploy antigen tests to quickly inform decisions.
Matukas said people living in long-term care will continue to be a priority for diagnostic testing.
Living in an area with a high prevalence of the disease, taking part in certain activities — such as waiting tables, driving a cab or attending a large gathering — and not using personal protective equipment also contribute to the risk.
On the other hand, scolding people for breakdowns that can’t be controlled could drive some people underground and make it harder to detect cases, Matukas said.
The Canadian government says it will donate up to 200,000 vaccine doses to fight the mpox outbreak in Congo and other African countries.
It says the donated doses of Imvamune will come from Canada’s existing supply and will not affect the country’s preparedness for mpox cases in this country.
Minister of Health Mark Holland says the donation “will help to protect those in the most affected regions of Africa and will help prevent further spread of the virus.”
Dr. Madhukar Pai, Canada research chair in epidemiology and global health, says although the donation is welcome, it is a very small portion of the estimated 10 million vaccine doses needed to control the outbreak.
Vaccine donations from wealthier countries have only recently started arriving in Africa, almost a month after the World Health Organization declared the mpox outbreak a public health emergency of international concern.
A few days after the declaration in August, Global Affairs Canada announced a contribution of $1 million for mpox surveillance, diagnostic tools, research and community awareness in Africa.
On Thursday, the Africa Centres for Disease Control and Prevention said mpox is still on the rise and that testing rates are “insufficient” across the continent.
Jason Kindrachuk, Canada research chair in emerging viruses at the University of Manitoba, said donating vaccines, in addition to supporting surveillance and diagnostic tests, is “massively important.”
But Kindrachuk, who has worked on the ground in Congo during the epidemic, also said that the international response to the mpox outbreak is “better late than never (but) better never late.”
“It would have been fantastic for us globally to not be in this position by having provided doses a much, much longer time prior than when we are,” he said, noting that the outbreak of clade I mpox in Congo started in early 2023.
Clade II mpox, endemic in regions of West Africa, came to the world’s attention even earlier — in 2022 — as that strain of virus spread to other countries, including Canada.
Two doses are recommended for mpox vaccination, so the donation may only benefit 100,000 people, Pai said.
Pai questioned whether Canada is contributing enough, as the federal government hasn’t said what percentage of its mpox vaccine stockpile it is donating.
“Small donations are simply not going to help end this crisis. We need to show greater solidarity and support,” he said in an email.
“That is the biggest lesson from the COVID-19 pandemic — our collective safety is tied with that of other nations.”
This report by The Canadian Press was first published Sept. 13, 2024.
Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.
HALIFAX – The Nova Scotia government says it could be months before it reveals how many people are on the wait-list for a family doctor.
The head of the province’s health authority told reporters Wednesday that the government won’t release updated data until the 160,000 people who were on the wait-list in June are contacted to verify whether they still need primary care.
Karen Oldfield said Nova Scotia Health is working on validating the primary care wait-list data before posting new numbers, and that work may take a matter of months. The most recent public wait-list figures are from June 1, when 160,234 people, or about 16 per cent of the population, were on it.
“It’s going to take time to make 160,000 calls,” Oldfield said. “We are not talking weeks, we are talking months.”
The interim CEO and president of Nova Scotia Health said people on the list are being asked where they live, whether they still need a family doctor, and to give an update on their health.
A spokesperson with the province’s Health Department says the government and its health authority are “working hard” to turn the wait-list registry into a useful tool, adding that the data will be shared once it is validated.
Nova Scotia’s NDP are calling on Premier Tim Houston to immediately release statistics on how many people are looking for a family doctor. On Tuesday, the NDP introduced a bill that would require the health minister to make the number public every month.
“It is unacceptable for the list to be more than three months out of date,” NDP Leader Claudia Chender said Tuesday.
Chender said releasing this data regularly is vital so Nova Scotians can track the government’s progress on its main 2021 campaign promise: fixing health care.
The number of people in need of a family doctor has more than doubled between the 2021 summer election campaign and June 2024. Since September 2021 about 300 doctors have been added to the provincial health system, the Health Department said.
“We’ll know if Tim Houston is keeping his 2021 election promise to fix health care when Nova Scotians are attached to primary care,” Chender said.
This report by The Canadian Press was first published Sept. 11, 2024.
ST. JOHN’S, N.L. – Newfoundland and Labrador‘s chief medical officer is monitoring the rise of whooping cough infections across the province as cases of the highly contagious disease continue to grow across Canada.
Dr. Janice Fitzgerald says that so far this year, the province has recorded 230 confirmed cases of the vaccine-preventable respiratory tract infection, also known as pertussis.
Late last month, Quebec reported more than 11,000 cases during the same time period, while Ontario counted 470 cases, well above the five-year average of 98. In Quebec, the majority of patients are between the ages of 10 and 14.
Meanwhile, New Brunswick has declared a whooping cough outbreak across the province. A total of 141 cases were reported by last month, exceeding the five-year average of 34.
The disease can lead to severe complications among vulnerable populations including infants, who are at the highest risk of suffering from complications like pneumonia and seizures. Symptoms may start with a runny nose, mild fever and cough, then progress to severe coughing accompanied by a distinctive “whooping” sound during inhalation.
“The public, especially pregnant people and those in close contact with infants, are encouraged to be aware of symptoms related to pertussis and to ensure vaccinations are up to date,” Newfoundland and Labrador’s Health Department said in a statement.
Whooping cough can be treated with antibiotics, but vaccination is the most effective way to control the spread of the disease. As a result, the province has expanded immunization efforts this school year. While booster doses are already offered in Grade 9, the vaccine is now being offered to Grade 8 students as well.
Public health officials say whooping cough is a cyclical disease that increases every two to five or six years.
Meanwhile, New Brunswick’s acting chief medical officer of health expects the current case count to get worse before tapering off.
A rise in whooping cough cases has also been reported in the United States and elsewhere. The Pan American Health Organization issued an alert in July encouraging countries to ramp up their surveillance and vaccination coverage.
This report by The Canadian Press was first published Sept. 10, 2024.
