Mask as needed: wastewater data shows COVID levels still higher than last June

When it comes to masking to curb the spread of COVID-19 these days, there's no specific rules people need to follow, local medical officers of health say. It will 'vary according to individual comfort levels' but also know, outside is better than inside, they say.

COVID-19 can be 'very inconvenient to you and your life,' Dr. Nicola Mercer says

Shoppers, some wearing face coverings and others not, are seen inside the Toronto Eaton Centre mall on March 24. Mask mandates have been lifted, but some people still aren't sure whether they should be wearing a mask or not (Evan Mitsui/CBC)

Go into any store these days and there's a mixture of people wearing masks to prevent the spread of COVID-19 and those who are opting not to wear one.

It may have people feeling like they're in COVID-19 limbo.

Dr. Hsiu-Li Wang, the Region of Waterloo's medical officer of health, says currently there's "no cut and dry threshold" when it comes to mask wearing and "it will vary according to individual comfort levels."

"My recommendation is for people to increase layers of protection during periods of higher risk and reduce those during periods of lower risk," she said in an email.

"Barring the emergence of new variants that would change the trajectory of our curve, we are transitioning toward low levels of risk within the next few weeks."

Dr. Nicola Mercer, the medical officer of health and CEO of Wellington-Dufferin-Guelph Public Health, says she "can't say that there's ever a completely safe place" to go without a mask, but outdoors is better than indoors.

She said ensuring all members of a person's family are up-to-date on vaccinations reduces the risk of getting COVID-19.

Dr. Nicola Mercer, the medical officer of health and CEO of Wellington-Dufferin-Guelph Public Health, wears a mask and visor in this photo from January 2021. (Hala Ghonaim/CBC)

The important thing people need to remember, Mercer said, is that COVID-19 is still circulating in the community and it can be "very inconvenient to you and your life."

And, she added, people can catch the virus more than once.

LISTEN | Dr. Nicola Mercer on what to do if you feel like you're in COVID limbo.

There's a mix of people wearing masks and those not wearing them in any store these days. Dr. Nicola Mercer, medical officer of health and CEO of Wellington-Dufferin-Guelph Public Health, talks about what people should do if they feel like they're in COVID limbo.

COVID in wastewater on decline

On Tuesday, Region of Waterloo Public Health updated its dashboard to reflect the latest COVID-19 numbers. 

There were no new deaths reported since the previous update on Friday, with the total number of COVID-related deaths in the region sitting at 420.

There were two active outbreaks — one each in a congregate setting and long-term care home — and eight people were in Waterloo region hospitals with the virus.

Wang and Mercer both consider these numbers while also looking at wastewater data to determine how much COVID-19 is in the community.

Mark Servos, a professor in the biology department at the University of Waterloo and the Canada Research Chair in water quality protection, is leading the research into searching for COVID-19 markers in the region's wastewater.

The researchers take samples from three locations — near wastewater stations in Cambridge, Kitchener and Waterloo — and look for COVID-19 signals in those samples.

"In the last month, we've seen a consistent decline in the signal," he said. "But it's a very slow decline and the levels are still higher than we saw last summer."

Servos noted they've found the Omicron subvariant called BA.2.12.1 has been increasing over the last month and is "taking over" the BA.2 variant.

These graphs show the COVID-19 signal in wastewater over the past year and a half, 2022 shaded on the right. These graphs were updated on the Region of Waterloo's COVID-19 wastewater surveillance dashboard on Friday, June 3. (Region of Waterloo/COVID-19 Wastewater Surveillance dashboard)

As well, they're also testing the water for BA.4 and BA.5, Omicron subvariants which were upgraded to variants of concern by the European Centre for Disease Prevention and Control in May. The subvariants have been found in North America but not yet in Waterloo region.

Wastewater testing in future

Servos said he expects to continue testing wastewater for COVID-19 for at least the next 12 months.

"The wastewater is one of the best tools that we have available to inform society of any rapid changes that might occur," he said.

While that specific work will wrap eventually, he says researchers have learned so much from COVID.

"We're going to use that knowledge to create programs to better protect and inform our public health," he said, noting that could mean surveillance programs for other kinds of diseases.

"We need to be vigilant about these kinds of diseases. We need to have surveillance. We need to be prepared for the future. And if we're not prepared, we don't learn the lessons of the past, then we're going to pay a big price in our society."


Kate Bueckert


Kate has been covering issues in southern Ontario for more than 15 years. She currently works for CBC Kitchener-Waterloo. Email:


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