Unlike vaccines for other illnesses, the influenza shot has to be remade from scratch every year because the viruses in circulation mutate each flu season. But a recent breakthrough by Canadian researchers marks an exciting step some experts say brings us closer to making a universal flu vaccine a reality
In a small room at GlaxoSmithKline’s sprawling vaccine manufacturing plant in Sainte-Foy, Que., two workers clad in hazmat gear are overseeing the fate of this year’s flu shot. A powerful heat lamp removes the outer packaging from a container of syringes before a conveyor belt transports them for filling and fitting with needles and stoppers. The air in the room is changed dozens of times an hour in order to keep the environment sterile.
This is just one step in the six-to-eight-month process of getting the yearly influenza vaccine ready for the public. Although this year’s flu season is just beginning, preparations have been under way at plants such as this one for the better part of a year.
During vaccine production, the facility uses approximately 360,000 eggs a day to incubate the flu virus before they are inactivated and processed. The finished vaccine is stored in a large temperature-controlled tank before a small hose-like line is used to fill thousands of vials and syringes. After multiple quality-control measures to catch mistakes, and a final safety check that looks for 37 possible defects, a finished batch is deemed ready for shipment.
This laborious process must be repeated each year: Unlike vaccines for other illnesses, the flu shot has to be remade from scratch every year because the viruses in circulation mutate each flu season.