100 million eggs per year for influenza vaccine production

The use of eggs for the production of influenza vaccines began in the early 1940s, when the global company CSL produced 1 million doses of a new influenza virus vaccine using an egg-based method pioneered by Australian virologist Macfarlane Burnet. Shortly thereafter, seasonal production began, and egg-based production became the mainstay of influenza vaccine production worldwide.

One British company uses about 600,000 eggs a day for flu vaccinations around the world. Dr. Beverley Taylor, head of global influenza science policy at CSL Seqirus, said eggsare very good incubators for growing some viruses. She told BBC Farming Today: “They allow us to extract some of the virus from eggs so we can get enough flu vaccines to protect millions of people every year. We source our eggs from specialized farms that exclusively supply us0 - these farms have a very high level of biosecurity and very strict controls on site about who can enter. We also regularly inspect and audit facilities to ensure standards are met,” says Taylor.

Over half a million eggs per day

“We process about 600,000 eggs a day, 7 days a week most of the year because we ship to both the northern and southern hemispheres - about 4 million eggs a week and over 100 million eggs a year, which is a huge number” , she notes.

The process involved pre-incubating the eggs and then mass vaccinating them: “We vaccinate the eggs with the virus. We let the virus grow for a few days, and then we collect the allantoid fluid - egg white - and that's where we get the virus .”

There are other alternatives as well. The company manufactures cell-based influenza vaccines at its North Carolina, United States facility , and many other influenza vaccine production platforms are currently under development.