Q: How can I tell if my child has allergies or just a common cold?
A: Symptoms of allergies and colds can be similar, but here's how to tell the difference:
Occurrence of symptoms Both allergies and colds cause symptoms of sneezing, congestion, runny nose, watery eyes, fatigue and headaches. Colds often cause symptoms one at a time: first sneezing, then a runny nose and congestion. Allergies cause symptoms that occur all at once.
Duration of symptoms Cold symptoms generally last seven to 10 days, whereas allergy symptoms continue with exposure to the allergen (symptom trigger) and subside soon after elimination of allergen exposure.
Mucus discharge Colds may cause yellowish nasal discharge, suggesting an infectious cause. Allergies generally cause clear, thin, watery discharge.
Time of year Colds more typically occur during the winter months, whereas seasonal allergies are more common in the spring through the fall, when trees, plants and grasses are pollinating. Indoor allergies, however, can affect individuals year-round.
Presence of a fever Colds may be accompanied by a fever, but allergies are not usually associated with a fever.
Q: What types of plants produce the most allergenic pollen?
A: The type of pollen that most commonly causes allergic reactions comes from plants (trees, grasses and weeds) that typically do not bear fruit or flowers. These plants produce small, light, dry pollen granules in large quantities that can be carried through the air for miles. Common allergenic pollens include:
Weeds such as ragweed, sagebrush, redroot pigweed, lamb's quarters, goosefoot, tumbleweed and English plantain.
Grasses such as timothy grass, Kentucky bluegrass, Johnson grass, Bermuda grass, redtop grass, orchard grass, sweet vernal grass, perennial rye, salt grass, velvet grass and fescue.
Hardwood deciduous trees such as oak, ash, elm, birch, maple, alder, hazel, hickory, pecan, box and mountain cedar.
Q: What does a pollen count mean?
A: A pollen count is a measure of the amount of pollen in the air. Pollen counts are frequently included in local weather reports. The counts usually are reported for mold spores and three types of pollen: grasses, trees and weeds. The count is reported as grains of pollen per square meter of air collected over 24 hours. This number represents the concentration of all the pollen in the air in a certain area at a specific time. The pollen count is translated into a corresponding level: absent, low, medium or high.
In general, a "low" pollen count means that only people who are extremely sensitive to pollen will experience symptoms. A "medium" count means many people who are sensitive to pollen will experience symptoms, and a "high" count means most people with any sensitivity to pollen will experience symptoms.
Although the pollen count is approximate and fluctuates, it is useful as a general guide when you are trying to determine whether you should stay indoors to avoid pollen contact.
Q: Should I consider moving to decrease my allergy symptoms?
A: No. It is a fallacy that moving to a different geographic climate will help "cure" allergies. Most people who relocate to get away from pollens that cause their allergies tend to find that they eventually develop allergies to the plant pollens in the new area. Other airborne indoor allergens, such as dust or mold, can cause symptoms in any location.
Lu is an allergist at Sutter Gould Medical Center in Stockton. He is board-certified in allergy and immunology and has a special interest in food allergies, seasonal allergies, sinusitis, metal reactions and asthma.