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COVID-19: Should you be tested for coronavirus if you don’t have symptoms?

Experts recommend only getting tested if you believe you may have been exposed to someone who has tested positive

Up until the last week, many provinces had mostly been testing patients with COVID-19 who had persistent symptoms, including a cough, fever and shortness of breath. 

Now, some provinces and specific health units are allowing for tests to be done on asymptomatic people who feel fine but could potentially infect others despite not feeling unwell. 

But governments need to be more clear with the public about the availability of testing for everyone, why it may be more important for some, and have a clear, more targeted strategy about where to do the most testing, experts told Global News. 

Why asymptomatic people may need a test

Manitoba began testing people without symptoms last week and anyone can participate. Asymptomatic testing also became available on May 11 for Calgary residents who do not work from home.

In Ontario, expanded testing protocols were announced this week. Premier Doug Ford announced on May 24 that anyone who is concerned that they’ve been exposed to COVID-19 can get a test, even if they have no symptoms. 

Ford said at a press conference that more people need to come to testing centres so that the province can hit their testing targets. Testing rates in the last week have been between seven thousand to 11,000 a day, when the testing capacity is 25,000. 

Expanding testing to asymptomatic people is a step in the right direction, said Todd Coleman, an epidemiologist and assistant professor in health sciences at Wilfrid Laurier University in Waterloo, Ont. 

Referencing Ontario’s new policies, Coleman says asymptomatic people should have been able to get tested months ago. 

“There’s a large proportion of people who are asymptomatic. This just means we’ll be able to catch more people who may be spreading the virus without knowing,” he said. 

Research out of Iceland at the start of April showed that up to half of the people tested for COVID-19 in the country, the disease caused by the novel coronavirus, had no symptoms. 

Asymptomatic spread is also an issue highlighted by the U.S. Centre for Disease Control and Prevention (CDC), noting that the illness can be spread by people showing no symptoms. 

Another study from researchers at Simon Fraser University in British Columbia, along with academics in the Netherlands and Singapore, found that it’s fairly common for the coronavirus to be spread by asymptomatic people. 

“The idea is to cast the widest net that you can get, to get all the different possibilities of manifestations of the infection,” he said. 

But the messaging behind the new guidelines in Ontario needs to be better defined to the public, said Coleman.

The province has been unclear in the past about who is able to be tested for COVID-19, he added.

“A lot of the reasons why the testing guidelines weren’t met in the past is because of inconsistent messages and lack of clarity, especially on the part of people who are trying to get tests,” he said. 

Now, Ontario needs to be clear through a coordinated effort with the province’s public health agencies, along with Telehealth, to make it clear who is able to get a test and why, said Coleman. 

Should you get tested if you have no symptoms?

Along with clearer messaging that more are welcome to get tested, even without symptoms, there needs to be more clarity about what a COVID-19 test can and cannot tell you, said Ashleigh Tuite, an epidemiologist at the University of Toronto. 

“It’s not going to tell you if you’ve been infected in the past,” she said. “Even if you get a negative test result, it doesn’t necessarily mean that you are not infected right now.”

COVID-19 typically has an incubation period of five days, so it could take time from the point of infection for a person to actually test positive, she said. 

However, testing asymptomatic people is helpful for provinces to get a better handle of how many people are infected, she said. This way these individuals can quarantine themselves from the rest of the community until they are no longer infectious.

Social distancing protocols need to be continued to be followed and if you believe you’ve been directly exposed to someone with COVID-19, you need to quarantine for 14 days, she said.

“That’s something public health needs to work with, to ensure people get that message,” she said. 

Testing of asymptomatic people allows individuals to understand their own risk and risk to others, she said. It’s helpful that those with no symptoms who work front-line jobs can now get a test in places like Ontario and Manitoba, she said. 

While no one will be denied a test in those regions, Tuite recommends only getting tested if you believe you may be exposed to someone who has tested positive.

The Ontario government also announced on May 21 that by the end of this week, an expanded testing plan will be outlined that focuses on testing asymptomatic people who work high-risk jobs.  

“Testing is really key in moving forward to prevent resurgence of disease in the population and that’s going to involve more surveillance type pieces,” she said. 

Why provinces need to specify who needs a test the most

While it’s encouraging to see testing requirements expand in some regions, there needs to be a clear strategy behind it so that those who are most likely to be an asymptomatic carrier of the virus are found, said Jay Kaufman, an epidemiologist at McGill University in Montreal. 

Encouraging the population at random to come forward doesn’t provide that kind of targeted testing, he said.

“Having people elect to test themselves without any overall strategy or design will only waste resources and muddy the waters, since more worried people are not necessarily the people at highest risk,” he said. 

Expanding testing will never hurt and it’s always a better option then not allowing more people to be tested, said Jack Siemiatycki, an epidemiologist at the University of Montreal. It’s also helpful to target occupation groups that are high risk to uncover more cases, he said.

Siemiatycki wouldn’t recommend everyone in provinces that allow asymptomatic testing to show up though, as it’s not the best use of resources, he said. 

Random samplings in population centres where there are a higher number of cases, like Toronto and the Greater Toronto Area, might be more effective, he added.

“If people just show up, you don’t know who they are and you can’t really generalize to know what that represents,” he said.

Questions about COVID-19? Here are some things you need to know:

Symptoms can include fever, cough and difficulty breathing — very similar to a cold or flu. Some people can develop a more severe illness. People most at risk of this include older adults and people with severe chronic medical conditions like heart, lung or kidney disease. If you develop symptoms, contact public health authorities.

To prevent the virus from spreading, experts recommend frequent handwashing and coughing into your sleeve. They also recommend minimizing contact with others, staying home as much as possible and maintaining a distance of two metres from other people if you go out. In situations where you can’t keep a safe distance from others, public health officials recommend the use of a non-medical face mask or covering to prevent spreading the respiratory droplets that can carry the virus.

For full COVID-19 coverage from Global News, click here.

- Global News