Have you ever wondered why it is that we have such trouble with influenza? Why don’t we just get immunized once, and never need to worry again? Why is it that once we have had the “flu”, we can later “catch” the “flu” again and …
Have you ever wondered why it is that we have such trouble with influenza? Why don’t we just get immunized once, and never need to worry again? Why is it that once we have had the “flu”, we can later “catch” the “flu” again and …