The day will come soon when all flu vaccines are grown in cell culture, using genetic splicing techniques to provoke and immunologic (antibody) response rather than growing actual viruses in hen eggs.
For this year's H1N1 swine flu pandemic, we are relying mostly on old technology from the 1950s. This involves growing the flu virus in hen eggs, and extracting a dead virus (inactivated) for use in the vaccine. The new swine flu vaccine appears to be well tolerated, and will likely only be a problem for those with severe egg allergies. It will be important for healthcare workers, children, pregnant women and those with chronic conditions to receive it first.
It is ironic to think that the fact that the vaccine is being made by tried and true techniques is the very fact I and other flu experts are using to reassure people. This technology has been used for several decades safely. Fear of vaccines have often proven to be well out of proportion to the real risk. Administering a vaccine always comes down to a cost-benefit analysis, where the goal is to protect a population where more risk is to be found in the disease than in the vaccine given to protect you.
Vaccine manufacturers have a tough job. They must ensure sterility with careful precautions, and weather being maligned by the media and anxious parents over something like the mercury-containing additive thimerosal, which study after study has found to be safe. Vaccines are not very profitable, but they are important, and vaccine makers should be applauded rather than subject to knee-jerk criticism.Marc Siegel, MD, is an internist and professor of medicine at New York University and the author of False Alarm: The Truth About the Epidemic of Fear