WINNIPEG -- Some of Manitoba's top doctors have written an open letter that pleads with the public to obey COVID-19 public health orders to prevent hospitals from being overwhelmed.

"Our health system cannot manage the potential volume of what is coming our way if we do not do everything possible to limit the spread of this virus," reads the letter signed by the provincial medical leads of 16 specialties, including primary care, surgery and cardiac sciences.

"Manitoba case numbers are rising far too quickly. Hospital beds are starting to fill."

The province reported 291 new COVID-19 cases Tuesday and one death.

Daily case counts should not be so high, given that Manitoba has had varying degrees of restrictions on public gatherings and household social visits for months, said Dr. Bojan Paunovic, a signatory to the letter and the province's medical specialty lead of critical care.

"We're seeing case counts that ... are higher than they should be, I think, if the current restrictions were actually being followed," Paunovic said in an interview.

The daily number of people with COVID-19 being admitted in acute care is now double what it was earlier this year, he added.

The number of ICU beds now filled, including with non-COVID cases, now hovers close to 110, Paunovic said. That's greater than capacity before the pandemic erupted and is approaching the kind of numbers seen in the second wave during the fall and early winter.

Signs that some Manitobans are not following the rules have been increasing in recent weeks. Dr. Brent Roussin, chief public health officer, said the third wave has been driven partly by social gatherings, including house parties and play dates.

There have also been protests and rallies against public health orders, including one in Winnipeg last month that drew several hundred people.

The open letter states that while the public is frustrated with ongoing restrictions, health workers are also frustrated.

"We are tired, too. Health-care workers have been pushed to their limits during this pandemic and are exhausted," the letter reads.

Further increases in infections will add to the risk of more cancelled surgeries, fewer beds available for non-COVID cases, and fewer workers available to staff other areas of health care.

The third wave of the pandemic is different, Paunovic said, in that the average age of people requiring hospitalization has dropped sharply. Doctors are seeing more people in their 20s and 30s in intensive care, he said.

"Earlier this week, we even admitted an 18-year-old who needed to be in (intensive care) and on a ventilator."

 The open letter asks Manitobans to hang on for a few more weeks -- time to allow patients in hospital to be treated and more vaccines to be administered.

"We really need everyone to just really bite down a little bit harder and give us about another six weeks," said Dr. Edward Buchel, provincial specialty lead of surgery.

This report by The Canadian Press was first published May 4, 2021