"And as that is coming down toward the end of February, that's when we start to see that peak of influenza B activity into the spring and later season". Can you tell the difference between a case of the common cold and the flu?
Werker, Deputy Chief Medical Health Officer, says the flu can take very many forms during the flu season.
This year the flu is especially hard-hitting, with the number of reported influenza-related deaths last week doubling to a season-to-date total of 91.
Both hospitals are reporting cases from in-patient hospital and emergency room visits but not from their urgent care or clinics.
Despite concerns that the flu shot isn't working this year, Saskatchewan health officials say it's too early to confirm that notion.
"If you've already lost some of your health immunity due to having contracted flu one time, you certainly do not need to contract a second strain and that's the benefit of taking the vaccine", she said.
So bad that cases in states like Arizona are up more than 758 percent over the same time a year ago.
"The vaccine for this particular influenza, H3N2, is not particularly effective, it is basically considered of moderate effectiveness, which means 30-40% of cases will be avoided among people who have the vaccine", Dr McCauley said. The overall hospitalization rate for the week ending January 6 - 22.7 per 100,000 - is nearly double that of the previous week.
The results reveal remarkable synchrony in flu outbreaks right across the country - and that outbreaks are particularly synchronous in "big flu" years, when the virus is somewhat novel and there is little immunity in the population.
The new numbers indicate a sharp increase during the final week of 2017.
"These personal losses are a reminder for all of us that flu can be a serious illness, for young and old alike", Department for Public Health Acting Commissioner Dr. Jeffrey D. Howard. "Our experiments suggest that influenza virus antigens grown in systems other than eggs are more likely to elicit protective antibody responses against H3N2 viruses that are now circulating", he said in a press release.
The entire Salem Health system has seen a massive spike in flu cases since mid-November.
Dr Flenley said: "The rise is partly down to the Aussie flu that was expected - and had been planned for with the flu vaccine". Vaccinating students against the flu is one way to keep them healthy and focused on their academic success. And many new patients have to be seen in "nontraditional areas", such as waiting rooms.
Flu cases began picking up in late November and December.