Amid rising cases of COVID-19 in Canada and around the world, experts say there are still key unanswered questions about the virus and how it works.
Globally, the number of confirmed cases has climbed to more than 116,000 — including at least 93 cases in Canada — with 4,000 deaths, according to the latest figures.
On Monday, B.C. Provincial Medical Health Officer Dr. Bonnie Henry announced the country’s first death related to COVID-19 after a man in his 80s with pre-existing health conditions died from the virus at the Lynn Valley Care Centre in North Vancouver.
Another person from the nursing home also tested positive for the virus.
Across Canada there are 35 cases in Ontario, 32 in B.C., seven in Alberta and five in Quebec.
Here is a look at what experts still don’t know about the disease and what they are watching for.
Why is COVID-19 killing the elderly but not children?
Researchers at the Chinese Center for Disease Control and Prevention in Beijing looked at more than 72,000 confirmed cases from China as part of a recent analysis and found that children under the age of 10 accounted for fewer than 1 per cent of all infections.
Of the 1,023 deaths recorded in China at the time, none included children.
The WHO has reported that 2.4 percent of reported cases were children under 18 and just 0.2 per cent of cases were children who became critically ill.
“We see relatively few cases among children,” World Health Organization director general Tedros Adhanom Gheberyesus told reporters in February. “More research is needed to understand why.”
Dawn Bowdish, Canada Research Chair in aging and immunity at McMaster University, said it’s a mystery why COVID-19 isn’t following the pattern of other viruses, like seasonal flu, which is especially lethal for the very young and old.
“The reason why it’s not affecting children is a mystery. It’s unusual,” Bowdish told Global News.
“It’s not something we have seen before and we don’t know why that is.”
Bowdish said people with heart conditions, hypertension, diabetes and weak lungs are the most at risk and the conditions are found more often in older populations.
In many COVID-19 cases, people are essentially becoming infected with really serious pneumonia where their lungs fill with fluid.
“If your lungs are full of water you can’t get oxygen into your blood, so your heart compensates by beating hard and faster,” she said.
“This can put a huge stress on the heart and this why some people are dying.”
Will weather affect the virus?
U.S. President Donald Trump has repeatedly claimed warm weather will halt the spread of coronavirus, but experts say it’s too soon to tell.
“Now the virus we’re talking about … you know, a lot of people think that goes away in April with the heat,” Trump said last month.
Infection control epidemiologist Colin Furness said he’d like to be as optimistic as the president but right now there isn’t enough evidence and “we’ll have to wait and see.”
Furness said there are essentially two ways of getting the virus: direct contact with an infected person or touching a contaminated surface and then touching your face.
Coronaviruses are called enveloped viruses, said Furness, meaning the virus has an outer wrapping. How fragile that envelope is to heat will be tested in the coming months.
“Donald Trump is assuming the virus will behave just like the flu. I’m hoping it will behave a lot like flu, but we don’t know,” said Furness
When will a vaccine be ready?
There are no drugs or vaccines currently approved specifically for COVID-19 and it’s unclear when they will be ready.
There are two clinical trials in China and one in the U.S. evaluating remdesivir, an antiviral drug from Gilead Sciences Inc. that was also tested for Ebola, according to the Wall Street Journal.
Meanwhile, in the U.S. a health research institute in Seattle is preparing to test 45 volunteers with different doses of shots co-developed by NIH and Moderna Inc.
And Inovio Pharmaceuticals — a DNA-based immunotherapy and vaccine company — is beginning safety tests of its vaccine next month in a few dozen volunteers at the University of Pennsylvania and a testing centre in Kansas City, Missouri, followed by a similar study in China and South Korea.
Doctors at a hospital in Wuhan are also conducting clinical trials using a combination of two drugs for HIV that had been tested on MERS patients in Saudi Arabia.
“As we get the data from those trials, that will really help inform decisions clinicians make about treating these infections in Canada,” Bowdish said.
“Because we are later in the infection peak we are going to learn from China, South Korea and Italy.”
What is the case fatality rate?
The WHO has said the death rate from known cases is about 3.4 per cent, significantly higher than the seasonal flu, which is about 0.1 per cent according to the CDC.
The WHO calculation is based on the number of reported cases and deaths.
Some health officials have said the 3.4-per cent mortality rate could be much lower, as about 70 to 80 per cent of people who get COVID-19 only display mild symptoms or are asymptomatic and may never be counted among the reported cases.
Before a parliamentary committee last week, U.K. chief medical officer Chris Witty said he has a “reasonably high degree of confidence” that the real mortality rate is 1 per cent or lower. And former CDC director Tom called the number an “overestimate” in an interview with Bloomberg news last week.
“The big problem with asymptomatic cases is you may never know the true numbers,” Furness said.
“It’s a lot of guess work.”
How long can it survive on surfaces?
The WHO says it’s still unclear how long the virus can live on surfaces like a metal hand rail, a water glass at a restaurant, or a plastic credit card.
One review of 22 studies found that coronaviruses, like those that cause SARS or MERS, can last on surfaces such as metal, glass or plastic from two hours up to nine days. Warmer temperatures reduce how long the virus can survive, according to the review.
Public health agencies are advising people wipe down commonly-touched surfaced like countertops and doorknobs with household disinfectant wipes and cleaners.
Officials have also repeatedly said handwashing for more than 20 seconds with soap and warm water is the best way to prevent the spread of the illness.
How did the virus jump to humans?
COVID-19 likely came originally from bats before transferring through an intermediary host to humans, according to the WHO and researchers.
But it isn’t clear exactly how the virus made the jump to humans.
One theory is that the in-between animal may have been a pangolin — one of the most illegally trafficked mammals in the world — which is sold in wildlife markets for its meat and their scales used in traditional medicine. However, this idea was later rebuffed by scientists in China.View link »