EDMONTON -- Alberta's chief medical officer of health reported 961 cases of COVID-19 and four deaths Tuesday.

The province added 236 cases on Friday, 259 on Saturday, 246 on Sunday and 220 on Thanksgiving Monday.

Dr. Deena Hinshaw said the Edmonton zone remains Alberta's coronavirus hot spot with 1,444 out of the 2,615 active cases.

"I continue to be concerned about the rise in cases," Dr. Hinshaw said.

"Due to the long incubation period of COVID-19, it will be at least a week or two before we start to see the impact of the voluntary measures announced last week for Edmonton zone."

The latest deaths involved a woman in her 70s in the Edmonton zone, a woman in her 60s linked to the outbreak at Lifestyle Options Terra Losa in Edmonton, a woman in her 50s connected to the outbreak at Mill Woods Shepherd's Care Centre in Edmonton and a man in his 80s linked to the outbreak at Foothills Medical Centre in Calgary.

There are 97 people in hospital with COVID-19, including 13 in ICU, Hinshaw said.

The CMOH also reported 464 confirmed active cases at 209 schools across Alberta. Eighty-eight schools have outbreaks, and 21 of them are under watch.

Starting Wednesday, Alberta Health Services assessment sites will only conduct tests by appointment.

"We will make on-site testing quicker and more efficient. We will also reduce crowding in lines and help ensure everyone is tested as quickly and safely as possible," Hinshaw said.

Alberta has reported 20,956 cases and 286 deaths to date.