Common colds are sometimes mistaken as allergies and allergies are sometimes viewed as common colds. With both disorders used interchangeably by some people, it is important to know how to determine the disorders through identifying their differences.
Colds is caused by viruses, such as the corona virus, while allergies are brought about by an overactive immune system secondary to exposure to an allergen, an agent that the body systems view as foreign, according to Web MD. As per the publication, once a cold virus invades the body, the immune system generates a “counter-attack,” which explains why people have cough and colds. In an allergic reaction, the body releases chemicals called histamine, which causes swelling in the passageways of the nose, prompting a person to cough or sneeze.
Since colds are caused by viruses, the condition can be transmitted from one person to another through droplet transmission. This mode of transmission involves coughing, sneezing, or contact with fluids with the infected droplet. On the other hand, allergies are not contagious, since it is caused by the body’s hypersensitivity; however, there are some cases, in which the condition is passed from a parent to the offspring. Thus, allergies are not contagious, but can be inherited.
Boston Children’s Hospital allergen immunotherapy director Dr. Rima Rachid told Live Science that people with one parent who had any type of allergy had a one in three chance of developing an allergy. Rachid added that when both parents had allergies, their children had a seven in ten chance of developing allergies as well.
Aside from etiology and transmission, common colds and allergies do have several other differences. According to Web MD, both conditions vary in terms of onset and duration. Common colds most usually happen in the winter in some regions; however it is possible at any time. The symptoms take a few days to appear following the infection with the virus. On the other hand, allergies happen at any time through the year; however, allergy triggers or allergens appear on a seasonal basis. In addition, allergy symptoms can begin as soon as possible following the exposure to the allergy trigger. With regard the duration, common colds lasts for three to 14 days while allergies may last within days to months, depending on the presence of and contact with the allergy trigger.
Common cold, which may be runny or stuffy nose, is often accompanied by cough and/or sore throat while allergies often present runny or stuffy nose with itchy and watery eyes. Both conditions may involve fatigue or weakness due to the impairment of airway clearance and potential effect to the gas exchange. Common colds are rarely accompanied by fever and itchy, watery eyes while allergy is never accompanied by fever and body aches.
The color of the nasal discharge also provides clues on whether the condition is common colds or allergy. In the same interview with Live Science, Rachid said that the nasal discharge of a person with common colds was usually green or yellow, due to the associated infection. On the other hand, seasonal allergies usually have clear nasal secretions; however, sinus infections may also result to yellow-colored nasal discharged.
Rachid also pointed out another difference between common colds and allergy, and that is the “allergic salute.” According to Rachid, the “allergic salute” could be a telltale sign of season allergies. Sometimes, children may be noticed to often push their noses up with the palms of the hands to wipe it or relieve itchiness. This can also be observed by looking at the skin of the child’s nose. Rachid said that when the salute was done frequently, it could cause a small crease at the bridge of the nose.
It should be noted that the most significant difference between common colds and allergy is that the former does not usually last for more than 14 days. If a person experiences common colds for 14 days, he should see his doctor for further medical assessment, intervention, and advice, as these could be allergy symptoms or signs of another health problem.