Alberta's contact tracing raises red flags as 43% of new cases have no known source

COVID-19 cases are rising in Alberta, and there are concerns that difficulties involved in contact tracing — both manual and digital — could hamper the province's ability to slow the spread.  https://www.cbc.ca/news/canada/calgary/alberta-contact-tracing-concerns-1.5766825?cmp=rss #news/canada/calgary