Answer
In order to identify if a forwarded email sent to you is a legitimate warning or a hoax you should try to find the author. Also note if the phrase "this is not a hoax" appears. The email is also likely a hoax if and you've never heard of the source, or it is sensational or emphatic and contains irregular capitalized letters, if it has questionable references or it has been debunked on reputable sites.
Work Step by Step
See the above.
