Is it COVID or a cold? How to know as Omicron cases rise
No specific symptom — or lack of one — can say for sure it's COVID. You have to test
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The Public Health Agency of Canada (PHAC) says a resurgence of COVID-19 appears to be underway, fuelled by the highly transmissible Omicron variant. At the same time, most COVID restrictions have been lifted across the country, more adults are heading back to workplaces, and kids, for the most part, no longer have to wear masks in schools.
"As of March 31, daily average case counts have increased by 28 per cent nationally," Canada's Chief Public Health Officer Theresa Tam said during a briefing last week.
It seems everyone either knows someone who is sick or they are sick themselves. Two of the doctors who spoke to CBC News for this story recently tested positive.
But with limited access to PCR tests across Canada, some who are getting sick are wondering if they have COVID or a cold or the flu — and what they should do if they have COVID-like symptoms but don't actually feel so unwell.
We'll answer some of those questions here.
Is it COVID or just a cold?
It's impossible to know for sure whether you have COVID-19 without a test, said Dr. Shazma Mithani, an emergency physician in Edmonton.
"There's no specific symptom or lack of symptom that can say for sure it is COVID or not."
The current list of possible COVID-19 symptoms in Canada is long – 14 in all. And PHAC warns that symptoms vary from one person to another, and that age can be a factor.
Right now, some of the most commonly experienced symptoms of COVID-19 include:
- Sore throat.
- Runny nose.
- New or worsening cough.
- Shortness of breath or difficulty breathing.
- Temperature equal to or more than 38 C.
"Many people who have COVID infection feel almost nothing or very mild symptoms — especially if they're young and healthy — versus some people as they start to get into their 40s, 50s and upwards seem to be much more symptomatic," said Dr. Lisa Barrett, an infectious disease doctor and researcher at Dalhousie University in Halifax.
And a once telltale sign has all but disappeared.
"That loss of taste and smell, which was kind of a warning symptom of, like, this is very likely COVID … that has evolved out of the virus, where it's less prominent now," said Barrett.
What doctors say they are seeing more of with Omicron is gastrointestinal symptoms, especially diarrhea, but also vomiting and abdominal pain.
Still, the bottom line is that testing is the only way to know for sure whether you have COVID-19.
If you have manageable symptoms, like a mild cold, should you still do a COVID-19 test?
Doctors say yes.
"The purpose of a rapid test is not to tell you you're not infected," said Barrett.
"The purpose of a rapid test at this point is to tell you, if you do have a positive, that it's highly likely that you have Omicron, or COVID."
And knowing that is important for several reasons.
"If you're a person at high risk, getting a test would make you eligible for antiviral treatment," said Dr. Kashif Pirzada, an emergency physician in Toronto.
He recommends anyone who is elderly, immunocompromised, or who has multiple medical conditions to get a rapid antigen test at the very least, though a PCR would be best. Still, he said a positive rapid test "would put you in line to get these new antiviral medications," including Remdesivir or Paxlovid.
Rapid testing is also recommended if you are young or otherwise healthy, for a few reasons.
"In the case of a situation where somebody might be unfortunate enough to develop long COVID, it's important to have that documentation of having had COVID," said Mithani.
She said it's also important to know so that you can let anyone you were in close contact with know that they've been exposed to the virus.
I've heard rapid tests don't work on Omicron, so what's the use?
It's not entirely clear yet why the rapid tests don't seem to pick up Omicron as effectively as they picked up earlier variants.
Barrett said it is too early to know whether it is the variant itself that is more difficult to pick up, or whether there is less viral load to detect because people getting sick have some level of immunity from vaccination or previous infection.
But there are ways to make the test more effective.
First, test more often.
"Testing every 24 hours while you're symptomatic," said Mithani.
"For at least for every single day that you're symptomatic, I would test every day if you have access to that number of rapid tests. If not, then you can stretch it out every one to two, or one to three days, just to ration tests a little bit."
Second, go beyond your nose.
"Swab both your throat and your nose to improve the sensitivity or the accuracy of the test," said Mithani.
She advises swabbing your throat first, around where your tonsils are and where the uvula is in the middle.
"Swab it aggressively," she said, "and then swab both of your nostrils."
Pirzada said you can swab your cheek, too, in between doing your throat and nose.
That said, he points out some rapid tests have been found to perform better than others. And all of the doctors agreed that just because you test negative, that does not mean you don't have COVID.
"As soon as you develop any cold-like symptoms, that's a sign that you might have it," said Pirzada.
"The rapid test, even if it's negative, don't take that as gospel, especially right now."
Does the colour of nasal discharge indicate whether it is more likely COVID?
No. Coloured mucus — green or yellow, and sometimes foul-smelling — often comes from a sinus infection, said Pirzada, which can be bacterial. But he said clear or coloured mucus will not tell you with any certainty whether it is COVID. You need to test.
I don't know anyone with the flu — is it still around?
Influenza rates remain low for this time of year, according to PHAC's FluWatch report. In fact, it says there has been "no evidence of community circulation of influenza" during the entire 2021-2022 season.
Despite doing similar numbers of lab tests for flu, the test positivity rate is "exceptionally low" across Canada, at 0.13 per cent, compared to an average of 23 per cent test positivity for the same period in the past six pre-pandemic seasons.
This flu season (which began Aug. 29, 2021) has seen just 551 influenza detections reported, compared to an average of 38,193 by this point in the past six pre-pandemic flu seasons.
Mithani said doctors are seeing cases of influenza in Edmonton hospitals, and if someone high-risk comes in with symptoms and tests negative for COVID-19, they will be tested for influenza. It's much the same in other provinces, too.
Pirzada said anyone high risk in Ontario will also be tested for influenza if the COVID PCR test in hospital is negative.
"So we are still testing for it, it's just not coming back positive very often," said Pirzada.
"Some strains of flu have actually gone extinct since the pandemic started."
Young children who present at hospital with COVID-like symptoms will also be tested for flu and other respiratory illnesses, including RSV.
If people are masking and being careful, why are they still getting colds or flu?
While COVID-19 is primarily airborne, colds and flu spread more on surfaces, too, so Pirzada said it's possible people are catching them that way.
The other thing, he said, is children.
"Children are spreading these viruses with gusto with each other, and they're bringing it home. And then you, if you have children, are spreading it to other people at your workplace."
The best way to avoid colds and flu, in addition to continuing to wear a mask, is the age-old advice to wash your hands and not touch your face.
What's the biggest misunderstanding about COVID-19 right now?
"The most dangerous one is that COVID living means pretending it's not around," said Barrett.
"That if you are somebody who wants to live with COVID, that you have to forget about it and just do what you did before COVID — the same amount of interaction, the same type of interaction without a mask, no testing, no isolation. That is the dangerous misconception."
Pirzada said it's also important to remember that if you get COVID, it doesn't mean you won't get it again.
"Even if if you get sick now ... immunity to COVID is very short, so you could get sick in the next wave in two or three months."
He said there needs to be a move to policies that cut down on the amount of circulating virus, "like good ventilation, masking in indoor spaces when there's big waves like this, and the rapid tests."
"The most important thing is what I call the vaccine-plus plan," said Barrett.
"Which is get all the [vaccine] doses that you're eligible to get. Wear a mask indoors — it's not perfect, but it's certainly helpful. And then, where available, test and isolate and keep your contact number moderate. You don't have to stay home, but keeping it moderate."
She said that if you do go out to a restaurant or other indoor gathering without wearing a mask, try to avoid seeing vulnerable people for three days after to make sure you don't develop symptoms. And if you need to interact with someone who is high risk, distance, wear a mask and practise good hand hygiene.