Alberta broke another record on Thursday with 4,921 active cases of COVID-19 reported.The province logged 477 new cases, continuing a trend that has seen the daily total average more than 450 new cases for more than a week.Five more deaths were reported on Thursday. They involved: * a man in his 40s from the South zone * a woman in her 80s linked to the outbreak in Agecare Skypointe in the Calgary zone * a man in his 90s from the Calgary zone who was not a resident in continuing care. * a man in his 90s linked to the outbreak at Mount Royal Revera in the Calgary zone.On Thursday, 130 people were being treated in Alberta hospitals for COVID-19, including 18 in ICU beds.Symptom list changes Starting Monday, the COVID-19 symptom list for Albertans under the age of 18 is changing. Runny nose and sore throat will be removed from the list of symptoms that require mandatory isolation for children."When we developed the symptoms checklist, we did so with the utmost of caution, with the information available at the time, and with an intent to prevent widespread transmission in schools," Dr. Deena Hinshaw, Alberta's chief medical officer of health, said Thursday at a news conference."As with all of our public health measures, we developed the list knowing that we would revise our approach if needed, based on new evidence and learnings from other jurisdictions."The changes to the symptom list, Hinshaw said, are intended to get children and teenagers back into child care or classrooms as quickly and safely as possible, while minimizing the risk of COVID-19.In the last week, she said, more than 3,400 children and youth who were tested for COVID-19 reported having a sore throat. Just over 700 of them had a sore throat as their only symptom, and less than one per cent of their tests came back positive.More than 3,300 children were tested with a runny nose, about 600 of them who had a runny nose and no other symptoms. Less than 0.5 per cent of those tested positive for COVID-19."This shows us that these symptoms by themselves are very poor indicators of whether a child has the virus," Hinshaw said. "Based on our data so far, the risk that a child with just one of these symptoms has COVID is even lower if that child is not known to be a close contact of someone with COVID-19."The change only applies to those who have not had exposure to a known case of the illness, she said.'More targeted checklist'The province will also shift toward what Hinshaw called a "more targeted checklist" that takes into account the total number of symptoms a child has.Any child who has even one of the core isolation symptoms of cough, fever, shortness of breath, or a new core isolation symptom of a loss of taste or smell, will still have to isolate for 10 days, she said, or have a negative test result and resolved symptoms before resuming activities.But starting on Monday, if a child has only one of any of the other symptoms on the list, they should stay home and monitor for 24 hours."If their symptom is improving after 24 hours, testing is not necessary and they can return to normal activities when they feel well enough," Hinshaw said.For children with two or more symptoms on the list, testing will still be recommended and they should stay home until symptoms go away or they test negative."Once again, we are acting on the evidence, which shows that any one of these symptoms individually is a poor indicator that a child has COVID-19," she said. "However, two or more symptoms increases the risk and so changes the approach that we need to take."Alberta's changes align with similar ones made in B.C., Ontario and Quebec, she said. "I believe this is a step forward for parents, teachers and child-care operators."The new checklist applies for all activities that children engage in, Hinshaw said, including sports cohorts, child care and school.The change does not include adults because the province is seeing different symptom trends among adults, she said.Latest numbersThe regional breakdown of active cases on Thursday was: * Edmonton zone: 2,277, an increase of 22 from the day before. * Calgary zone: 1,879, an increase of 91 from the day before. * North zone: 325, an increase of one from the day before. * South zone: 256, the same as the day before. * Central zone: 162, an increase of two from the day before. * Unknown: 22, a decrease of two from the day before.