It wasn't a usual, crowded protest.

On Sunday, a small group of doctors marched across the street from the Calgary Drop-In Centre, keeping two metres apart to adhere to social distancing recommendations and rules against mass gatherings.

The doctors say the government needs to act now to support those in health-care who work on the front-lines with Calgary's most vulnerable population — the homeless.

"The shelters are doing everything they can to keep people safe but we need public health measures immediately," said Dr. Christine Gibson.

"We can't even begin to imagine what's possible if the shelter becomes ill. One person becomes hundreds, becomes thousands in the general public, and we will flood the hospitals and we will be in a situation we have never been in before."

Christine Gibson says she would like to see more public health measures in Calgary's shelter system. 4:26

Gibson said it's time for the government to call in the Red Cross or military — anyone who can bring in extra support, regulatory action and the Personal Protective Equipment that she says health-care workers are already being asked to limit using as supplies are low.

On Friday, Alberta Premier Jason Kenney announced funding and staff to shelter and care for the province's homeless population during the coronavirus pandemic. He said the Mustard Seed and Drop-In Centre are working to block book hotels for additional space.

Dr. Bonnie Larson, one of the protest's organizers, said while that's a welcome response to help with overcrowding, it doesn't help with more urgent needs.

"We need a big, organized, system-level response and we could use reinforcements any minute, right now, yesterday," she said.

Larson said in recent days, she and other volunteers have found more people without housing who are sick, and said some could have COVID-19.

"These folks are going to be the ones ending up in the ICU, they are going to be the ones having a severe disease course," she said.

People experiencing homelessness and others in poverty are particularly at risk from the pandemic, according to a report published last week by the University of Calgary.

Gibson said shelters are doing everything they can to keep people safe, but are limited without regulatory action.

"It's obvious to me that we are putting the entire public at risk with our lack of screening, our lack of safety and precautionary equipment that's available to front-line workers and our lack of a collective response in the shelter system."

Calgary Mayor Naheed Nenshi outlines how they are planning to protect the vulnerable homeless people in the city. 2:21

On Saturday, Alberta's deputy chief medical officer of health Dr. Marcia Johnson said while Alberta Health isn't yet aware of any COVID-19 cases within the province's homeless population, they are monitoring the situation closely.

As of Sunday, there are 259 confirmed cases of COVID-19 in the province.