Current vaccine’s success rate is limited
Flu shots are made in three main ways but the most common and oldest method, dating back more than 70 years, is using hen’s eggs.
e egg-based production process begins with private-sector manufacturers who use candidate vaccine viruses (CVVS) grown in eggs per current regulatory requirements.
The CVVs are injected into fertilized eggs, which are incubated for several days to enable the viruses to replicate, to create large amounts of the u virus, and the fluid containing the virus is harvested from the egg.
The virus is then inactivated (killed) and purified to create an antigen, which induces an immune response in the body.
e problem with the current process, however, is that it takes too long to manufacture and distribute, has a short shelf life that diminishes monthly and has a relatively low rate of effectiveness.
e average rate of effectiveness with existing u shots is about 50 to 60 per cent, said researcher Dr. Murdo Ferguson.
But because of the emergence of a new u strain last year, that u shot was only about 35-per-cent e ective.
Influenza caused about 2,000 deaths in Canada last year and is considered a major killer around the world, which makes the new vaccine all the more important, he said.
And that is in addition to countless others who survived but who were really sick with the u virus.