Site Index Allergy Asthma Immune Disorders Glossary Online Resources Allergy and asthma are among the most common heath problems, with more than 50 million people afflicted with asthma, seasonal hay fever, or other allergy-related conditions each year.
Allergies can affect anyone, regardless of age, gender, race, or socioeconomic class.
Generally, allergies are more common in children, however, a first-time occurrence can happen at any age, or recur after many years of remission. There is a tendency for allergies to occur in families, although the exact genetic factors that cause it are not yet understood. Food allergies are seen in 3 percent of children. If one parent has allergies, there is a 40 percent chance of a child developing allergies. If both parents have allergies, this increases to a 75 percent chance that a child will be affected.