When is someone considered 'recovered' from COVID-19?
Doctor says recovery not 'a free pass to move about with impunity'
Blondine Arseneau got the good news from Public Health on April 1: she had officially recovered from COVID-19.
"It was a big relief," the 68-year-old Moncton woman says. "When you're sick like that, you never know what can happen."
Still, though her symptoms had retreated and her appetite was back, "I was not really 100 per cent satisfied because there are no tests anymore."
So she's been staying inside as much as possible, following the guidance from chief medical officer of health Dr. Jennifer Russell.
Arseneau is an example of a growing number of New Brunswick's COVID-19 cases: people who have recovered from the virus now make up close to two-thirds of all infections to date in the province.
In other words, there are almost two people who have recovered for every one person who is still sick.
It's a good-news number that raises a new set of questions: when is someone considered recovered, and how should they behave at that point? Are they immune, and if so, can they go back to the office?
Changing criteria
The criteria for "recovered" status have changed since the beginning of the outbreak, as new data and research have accumulated.
At first, public health officers across Canada decided patients with the virus should have two negative tests before they could be considered recovered.
But Russell said a growing body of evidence shows that if someone has a mild case, they are in the clear eight days after they first showed symptoms — if they're also free of symptoms at that point.
Some provinces have adopted a 10-day post-symptom period as their marker, just to be sure. New Brunswick has gone with 14 days, "to be the most cautious we can be around this issue," Russell says.
A more severe case "would be a different picture and a different story," she added. While Public Health isn't recommending follow-up testing in those cases either, some patients may want it and their doctors may opt to do it, she explained.
Patients like Arseneau who have recovered are also being urged to not assume they're now immune — advice she says she is happy to take.
Arseneau is visually impaired and said she's a homebody anyway. When she went out to mail something recently, she was startled and jumped away when someone approached and offered to help.
"I'm out of danger now, but I don't know if I can get it another time. It's not proven yet, so I don't want to take a chance."
Russell said that kind of caution is a good idea, even for recovered patients.
"You can carry on your normal life the way all the other people are carrying on their normal lives: with all the restrictions in place around social distancing."
That means leaving home only for essentials, wearing a mask and staying at least six feet away from other people.
Recovery not 'a free pass'
Dr. Raywat Deonandan, a global health expert and epidemiologist at the University of Ottawa, said it's wise to be cautious because of reports from Asia of "reactivated" illness in some recovered patients.
He said it's unlikely those patients caught COVID-19 a second time. It's more likely those patients weren't really as clear of their initial infection and they will still turn out to be immune eventually.
But until the evidence is clear, recovered patients should not take their recovery "as a free pass to move about with impunity. Not yet, though that day might come soon."
Russell said family members of a recovered patient would need to self-isolate for a period lagging the sick person's infection.
But that doesn't necessarily mean it's safe for the recovered person to become the designated grocery shopper or errand runner for the household.
"Each situation would be carefully assessed," she said. "These would be conversations the individual would have with their Public Health team."
She said tests for COVID-19 antibodies exist elsewhere but are not yet available in Canada. "We do expect in the long term to have those kinds of tests," she said.
Zone-by-zone breakdown
Last week, CBC News requested a breakdown of the number of recovered New Brunswick cases by health zone.
The current map released daily by the province shows only the cumulative total cases per zone, along with province-wide totals for active and recovered cases.
Russell said she had not been aware of the request but said showing zone-by-zone recoveries zone by zone could give people in some regions a false sense of security.
"If they look at a zone and think everyone's recovered there, and think, 'We don't have any COVID-19 here,' that's not entirely true," she said. "We don't know. Some people are asymptomatic or presymptomatic.
"We want people to continue to base their behaviours on the idea that COVID-19 is everywhere and you need to behave like everybody has it."