Using grep to search for a string that has a dot in it

I am trying to search for a string 0.49 (with dot) using the command

grep -r "0.49" *

But what happening is that I am also getting unwanted results which contains the string such as 0449, 0949 etc,. The thing is linux considering dot(.) as any character and bringing out all the results. But I want to get the result only for “0.49”.