20 Years or more: Since experince with this vaccine in japan for twenty years and in us for 15 years , have shown that immunity lasts gor 20 or more years, how long only experience will tell.
Answered 8/20/2014
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A doctor has provided 1 answer
A doctor has provided 1 answer
5 doctors weighed in across 2 answers
5 doctors weighed in across 2 answers
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