At least until the virus mutates.
As always, you can read more in DeHaan Services, where "Is it a Flu Epidemic or Simply a Fluke?" includes a Canadian public service announcement linking to Health Canada's FAQ for influenza.
One Healthful Writing Tip versus Flu Epidemics
This particular subject spanned from public health and clinical research organizations to math and statistics. Few people will know both subjects.
My editor and I worked hard to ensure that my article would be useful and informative to any audience, from a person concerned about their own family's health through both the health-care oriented and those who are mathematically inclined. How much to explain? Do we list definitions or slide them into the narrative?
When you write, ask whether all your readers will understand the jargon? If not, how will you introduce it?
Working out the answer to that riddle is one part of keeping your writing healthy, even when the subject concerns flu epidemics.