Hay fever also known as allergic rhinitis is an allergic disorder that occurs inside the nasal passage. Only people with sensitive immune system become victim to allergic rhinitis. When such people breathe in allergen like pollen, animal fur and dust, they start sneezing constantly. A person with hay fever suffers from problems like itching, swelling, and consistent formation of mucus in the nasal passage. They also from other problems like sore throat, wheezing, itchy eyes, etc. The reason why it is called hay fever is that it is usually common during the haying season. However, the disorder can happen throughout the year once a person inhales the allergens.
Fever blister or even known as cold sores are caused by herpes simplex virus 1. These are basically red blisters which appear on the outer edges of the mouth and on the lips. These blisters are filled with fluid which form scabs after few days and later form crusts which signal the end of this infection. Although there is no cure but there are certain home remedies for fever blisters which can alleviate the symptoms caused by it. Basically the symptoms of fever blisters can be itching, burning sensation, enlargement of lymph nodes and fever.
Fever is an elevation in body temperature above normal and is not necessarily dangerous unless it climbs higher than 103 degrees Fahrenheit. Normal body temperature varies from person to person and fluctuates widely throughout the day. Normal body temperature is generally considered to be within the range of 98 to 100 degrees Fahrenheit.