They are more likely to experience health problems
Well, we know that a lot of the ancient civilizations were first-handedly affected by disease. For example, Native Americans were severely impacted by the spread of pestilence. 90% of their population was completely killed off. I think that would be enough to concern them, don't you think? :P
Answer:
I saw this: Formaldehyde. ... Aluminum salts. ... Thimerosal. ... Chicken egg proteins. ... Gelatin. ... Antibiotics.
Explanation:
Just look up "What is in the flu vaccine" or "what ingredients can be found in a flu shot"
Hope this (kinda) helped :)