The most apparent sign of an immune deficiency disorder is frequent or unusual infections.
The number of infections vary in healthy people depending on several factors such as stress level, exposure to children in school, and the virulence of common viruses. This makes it harder to assess whether a person is experiencing an excessive number of infections.
The list shown below was adapted from the Jeffrey Modell Foundation’s 10 Warning Signs of a Primary Immunodeficiency (PID). Individuals who have experienced two or more of the following symptoms may have a primary immunodeficiency and should see an immunology specialist to evaluate for this:
Adults
Two or more new ear infections within 1 year
Two or more new sinus infections within 1 year, in the absence of allergy
One pneumonia per year (radiographically proven) for more than 1 year