A Shot in the Arm

I got my flu vaccine for free last week through Princeton Health Services. To encourage us to get vaccinated, there was an ad blitz campuswide for "FluFest", a two-day event at the student center which featured performances by our a cappella groups and free food.
I won't bother blogging about why you should get your flu vaccine, or complaining about misguided rants, because that's been done to death. Search blogger.com if you don't believe me.
For up-to-date information on the vaccine and the flu, click here to go to the Center for Disease Control's Website.
See here for more details about what's in the vaccine.
The two types of vaccine:
1) The trivalent inactivated influenza vaccine.--> I got this one.
"Trivalent" in this case means that the vaccine provides immunity to three different strains of the flu. The three strains in the vaccine change from year to year, depending on what health professionals have determined to be the most likely ones to be going around that particular flu season.
"Inactivated" means that the virus isn't infectious. You just get the parts of the virus that trick your immune system into doing its job. Mostly, that's the outer coating. It's like the story in the bible about how Jacob fooled his blind father Isaac into giving him the blessing intended for his hairier brother Esau, by wearing hairy goatskins.
2) The live, attenuated influenza vaccine.
"Attenuated" means weakened.
This vaccine is a nasal spray, not an injection.
The modified viruses for both types of the vaccine are grown in chicken eggs. This technology has been around since at least as far back as the 1950's, and it's why people with egg allergies shouldn't be given this kind of flu vaccine.
I searched PubMed for "embryonated hen's egg" and it looks like plenty of things can be grown in chicken eggs, like herpes simplex virus and hepatitis. I wonder why we still use this system. Seems to me like we should be able to make a synthetic, hypoallergenic cocoon for these things to grow by now.