They developed the theory of “channels” which carried blood, oxygen, & nutrients throughout the body.
Because vaccines have healthy viruses that try to get your body to be immune to the diseases so when you are already sick your body won't respond to the vaccine because it's just more viruses
Any disease that is contagious like the Flu. Something like Alzheimer's would not be considered an infectious disease.
Answer:
An evidence-based clinical practice guideline
Explanation:
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