The problem is that there is no "point" where one can be safely anti-vax. Vaccinations are typically not that effective on an individual basis, often as little as 50% or less. They require a minimum vaccinated population of between 85 and 95 percent to be effective; what is known as "herd immunity". There is a small percentage of the population that cannot be vaccinated because they're too young or have other medical problems that prevent it; or have weak immune systems due to illness, transplants, or simple old age. These people rely entirely on herd immunity for protection.
Flu vaccines are not always effective, because the virus mutates so quickly and unpredictably; so a lot of how effective a vaccination is depends on how good at guessing which particular virus is going to be the problem one that year. Some years they guess right, and the vaccine prevents a major outbreak; other years they guess wrong. However, some strains are absolutely predictable, and vaccinations can be extremely effective if they're gotten early enough.
One very good example was the recent swine flu outbreak. That was a particularly bad one, because it actually affected healthy people worse than weaker people (it caused what is known as a "cytokine storm" in the immune system, effectively sending it into overdrive and causing it to attack it's own body). Early and widespread vaccination kept it from becoming a major pandemic and killing nearly as many people as it did the last time it occurred.
Vaccines are not perfect, medical science is not that precise. But they're a hell of a lot better than the alternative.
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timeasmymeasure
no subject
Date: 2010-10-23 04:02 am (UTC)Flu vaccines are not always effective, because the virus mutates so quickly and unpredictably; so a lot of how effective a vaccination is depends on how good at guessing which particular virus is going to be the problem one that year. Some years they guess right, and the vaccine prevents a major outbreak; other years they guess wrong. However, some strains are absolutely predictable, and vaccinations can be extremely effective if they're gotten early enough.
One very good example was the recent swine flu outbreak. That was a particularly bad one, because it actually affected healthy people worse than weaker people (it caused what is known as a "cytokine storm" in the immune system, effectively sending it into overdrive and causing it to attack it's own body). Early and widespread vaccination kept it from becoming a major pandemic and killing nearly as many people as it did the last time it occurred.
Vaccines are not perfect, medical science is not that precise. But they're a hell of a lot better than the alternative.