Why may you be asked whether you are allergic to eggs before receiving a vaccination?

Some vaccines are made out of egg proteins, which is why it is imperative for those administering them to ask if the patient has an egg allergy. Some vaccines may cause a severe allergic reaction. However, if hives are all the patient gets from eggs, the vaccines are still administered. If they get more than hives, they are closely monitored if given the vaccine. 

Developed countries will see a decrease in natural resources, because their population will decrease.