It should definitely be mandated that every individual medically possible be given a battery of vaccinations, as well as subsequent booster shots when required.
I do not believe all vaccines should be mandatory, however. But there should be (and there are) rules in place governing the requirement for additional vaccinations to be administered depending on occupation and or location of work. As an example, in my work place, anybody that works with rabies in our BL3 labs MUST get the vaccinations and subsequent booster shots before being allowed to work under these conditions.
The problem today is the ever increasing globalization of everything. People, food and products can literally be moved around the world in 24 hours, which is more than enough time for viral and bacterial pathogens to remain in an infectious state. These agents are easily spread due to the sheer density of people that come into contact with one another on a daily basis.
As for the influenza vaccine, I personally don't get it annually, but as a scientist, I know it is becoming riskier every year not to get it. Influenza is a fascinating, smart, and ultimately evil virus, and it is only a matter of time before an extremely virulent strain emerges.
I was at a beer tasting on Friday night, and the instructor was telling us about an organic beer from a brewery that actually farmed all their own ingredients. They used guinea fowl and pigs to help control pests on the farm. This is actually horrifying, because inadvertently, this farm is creating the perfect conditions for the emergence of new influenza strains.
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