Is it an allergy or a common cold?

Did you know a sore throat or runny nose may be something other than a common cold? Taking a closer look at these and other symptoms can help you determine if it's a cold you're up against or allergies that may be affecting you.

Allergies occur year-round

If you're allergic to pollens, you may feel an improvement in spring and summer allergy symptoms during colder winter months. However, if you are sensitive to indoor allergens, such as mold, pet dander or dust mites, your allergy symptoms may be more pronounced during winter when you spend more time indoors, because your home's furnace dries the air and circulates allergen particles throughout your home.

Allergies and common cold differences

Colds are caused by contagious viruses, which are spread by sneezing, coughing, shaking hands or touching contaminated surfaces. Your immune system fights off the infection and your symptoms usually resolve after a couple of weeks.

Allergies are due to an immune reaction to something in the environment, such as dust or pollen. Both colds and allergies can cause nasal congestion, sneezing and coughing but allergies are not contagious and do not routinely resolve after a couple of weeks.

Consider these additional distinctions between colds and allergies:

• A runny, stuffy nose is common with both colds and allergies.
• Body aches are more likely to be present with colds than allergies.
• Colds most often occur during winter months. Allergies occur at any time of the year.
• Cold symptoms take a few days to appear after an infection. Allergy symptoms can begin immediately after contact with triggers.
• Colds tend to last anywhere from three to 14 days. Allergies can last days to months.
• Cough often is present with a cold and sometimes with allergies.
• Fatigue is sometimes present with both colds and allergies.
• Fever is rare with a cold and never with allergies.
• Itchy, watery eyes are rare with a cold but often with allergies.
• Sore throat is more likely with a cold than with allergies.
• The most crucial difference is that colds usually don't last longer than 14 days.

Common indoor or winter allergens

Even the cleanest of homes can be a hotbed for indoor allergens. Some of the main culprits include:

• Animal dander
  Despite what you may hear, breeds of dogs or cats touted as hypoallergenic still cause allergies whether or not they shed. People are not allergic to animal hair; they're allergic to an allergen found in the saliva, dander, or dead skin flakes, and urine of any mammal.
• Cockroach droppings
  Cockroaches are common pests whose droppings can cause environmental issues.
• Dust mites
  These microscopic pests thrive in warm, humid environments where skin flakes collect, such as bedding, upholstered furniture and carpeting.
• Indoor dust and mold
  Mold can colonize in a humidifier, causing more harm than good.

Tips to help reduce allergens in your home

There are a few suggestions you can try to help combat indoor allergens in your home:

• Block crevices, wall cracks and windows where cockroaches may enter. Keep food in containers with lids, use garbage cans with lids and wash dishes immediately after use. Clean under stoves, refrigerators and toasters where crumbs can accumulate.
• If you have indoor pets, keep them out of bedrooms and other rooms where you spend most of your time. Try to minimize contact and wash your hands after touching.
• Launder clothing regularly, particularly after being near pets or other allergens.
• Place zipped protectors on pillows and mattresses to keep out dust mites.
• Remove mold growth on hard surfaces in your home like bathrooms and kitchen with water, detergent and, if necessary, a 5% bleach mixture.
• Repair and seal leaking roofs or pipes. Use dehumidifiers in damp basements, making sure to empty and clean the unit regularly.
• Try to keep humidity levels low — around 40 to 50% — in your home.
• Use a high-efficiency particulate air, or HEPA, filter vacuum. These filters are rated at least 99.97% efficient at trapping particles of 0.3 microns in size.
• Vacuum carpets often, or replace carpet with hardwood floor, tile or linoleum.
• Wash all bedding weekly in hot water, which is about 130 F.

Richard Crockett, M.D., is an immunologist in Allergy & Asthma in Mankato and New Prague, Minnesota.