How about, "I trained my whole life and I'm a medical professional and I know what this does and it's good for you with no side effects, and it will prevent horrible diseases upon you, your family, and the world."? Does that work for you?
The medical profession has plenty of solid reasons for vaxxing the population - none of which the ignorant savages of the anti-vaxxer group ever pay attention to. Anti-vaxx groups are in the same category of intelligence as other, forbidden topic groups.
There is no logical argument that the anti-vaxxers can put forth to back their ridiculous and mildly insane claims. You creating excuses for them - based entirely on ignorance - just makes it worse. You're actually making the problem worse. Thanks?