Who does it affect?
Everybody is susceptible to having allergies, but they don't usually affect very young children or the elderly as often. Typical symptoms include runny nose, sneezing, coughing, and itchy throat and eyes.
Fevers can be a good gauge as to whether or not allergies are affecting you or if it's something more serious.
Allergies are not contagious, so if others around you are sick, and you are not, your symptoms likely allergies.