In the early dark days of the pandemic, when vaccines for what was then still sometimes referred to as the novel coronavirus were just a hope, researchers around the world started noticing a strange phenomenon.
A family member would come into the hospital with their loved one, who was struggling to breathe, or hooked up to a ventilator. But instead of also getting ill, this person seemed to have somehow dodged the virus altogether.
“Wait a minute. You live in the same house, in the same bed, you do everything together — he’s in the ICU and you’re not?” said Dr. Donald Vinh, an infectious-disease specialist and medical microbiologist at the McGill University Health Centre.
“It became very clear that there were people who were exposed without getting severe disease,” Vinh recalls, but the “burning question” was, did they just not have symptoms, or had they escaped the infection? And if so, how?
The sixth wave has brought an explosion of COVID in some Ontario communities, including Toronto, with for many, more friends and family members getting sick than ever before in the pandemic.
But for every story of someone out with the virus, it seems like there’s another of someone who was spared, despite an exposure, or even living in the same house as multiple people who tested positive. If you’ve sidestepped COVID so far, you probably have vaccines, masks, and luck on your side, experts say.
There is, however, a very small group of people who appear to have innate immunity to the virus. There’s actually a precedent for this with other diseases, and Canadian researchers hope that unlocking the mystery of these “COVID resistors” can help develop more effective treatments and vaccines.
For the average person who hasn’t been infected, “it’s probably because you’re doing all the right public health things,” said Dawn Bowdish, the Canada research chair in aging and immunity and a professor of medicine at McMaster University.
There are people out there, though, probably less than one per cent of the population, Bowdish estimates, who are “highly exposed but seronegative” — health-care workers, for example, who were in COVID wards without proper masks before vaccines. Unlike individuals who got it and were asymptomatic, this elite group never develop antibodies in their blood to the virus (and scientists can tell whether those antibodies are from the disease or the vaccine), possessing some kind of natural immunity.
Bowdish is a co-lead on a large study about COVID in long-term care and hypothesizes that certain individuals may have developed immunity after repeated exposure to other seasonal coronaviruses that cause the common cold.
“When they’re exposed to SARS-CoV-2 they pull up that immune response, and sort of help protect themselves,” she said. “Ninety-nine-point-nine per cent of us, we have to rely on our antibodies to do some of that work, whereas these other people use what we call T-cells” — another part of the immune system — that saw something very similar months or years ago and “jump into action and clear it out before it can even get started.”
McGill’s Vinh is the Canadian site lead for an international investigation looking at so-called “COVID resistors” that started as an effort to determine why some people get a severe bout of the disease. The team has identified about 700 people worldwide who qualify as exposed, test negative (with polymerase chain reaction (PCR) or rapid tests) and never developed antibodies.
“We’re hunting for the genetic basis for why people are resistant to COVID infection,” said Vinh.
“If we can actually understand the molecular basis by which humans are naturally resistant to infection, that first step, when the virus tries to get into our cells, it can guide logically and rationally the development of therapies,” he added.
If you’re still convinced you’re one of this tiny elite group, Vinh and his team are still actively recruiting for their study.
In Britain, one research group has taken this a step further in what’s called a human challenge study, where they deliberately exposed 36 healthy, young unvaccinated adults with the virus. The main aim was to find the infectious dose necessary for infection, but they also found that “interestingly, 50 per cent of volunteers did not become infected,” said Dr. Andrew Catchpole, chief scientist at hVIVO, the company that ran the study, recently published in Nature Medicine, in partnership with Imperial College London and the British government. Although they never expected everyone to become infected when using low doses, they are currently studying the immune responses of those who did get infected vs those who did not in the hope that this could help find future drugs, he added in an email.
After two years of “shots in the dark” with treatments, the idea with this kind of work is to start something that’s already happening in humans and go from there, said Vinh.
“Some people say, well isn’t that a bit far-fetched, it is, except that’s what science is supposed to be, it’s supposed to be far-fetched,” he said.“But it’s not unproven.”
Hundreds of years ago when the plague was decimating Europe, there were cases of people who simply never got it, despite sometimes losing their entire families to the disease.
One theory is that people who survived the Black Death had a “specific mutation in one of their immune cells that made them less likely to support the bacteria that caused the plague,” said McMaster’s Bowdish. Another famous example is a group of sex workers in Nairobi, Kenya who were exposed to HIV many times but never became infected.
The message for most people who have avoided COVID so far, is don’t rely on this innate immunity as some kind of hidden superpower, Bowdish added. “But I think the inspiring part about finding people like this is that it kind of gives immunologists who are making vaccines a hint about what they should be targeting those for.”
Her colleagues at McMaster, for example, are working on developing an inhaled vaccine that would ideally provide broader immunity against multiple variants of COVID, rather than racing to develop a specific vaccine each time the virus mutates.
“In a perfect world, our vaccines would do exactly what these people naturally do, shut down that infection before it even got started and you’d never carry it and you’d never transmit it,” Bowdish said. “And we’d all be able to go back to our 2019 life.”
May Warren is a Toronto-based breaking news reporter for the Star. Follow her on Twitter: @maywarren11
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.
