illnesses, for example, have been identified or suggested in some instances (Anderson and Korsgaard, 1986; Finnegan et al., 1984; Morey, 1988). Further information can be obtained from a review and an editorial by Kreiss (1988, 1990).
Assessments of disease magnitude often depend on a subject's recalling the occurrence of a disease and recognizing its relationship to allergy. For example, questionnaires will ask, "Have you had hay fever?" For an affirmative answer, the subject must recognize that his or her recurrent nasal symptoms are in fact due to an allergic nasal condition. Diary studies, that ask subjects to record symptoms on a daily basis, are another way of assessing the burden of respiratory symptoms in the population. In general, they suggest that respiratory symptoms are quite common, more so than recall studies would indicate. In a diary study of Manhattan (New York) residents, it was determined that the rates of symptoms were much greater when diaries were used than when subjects were asked to recall their health status over the past several years (Lebowitz et al., 1972a,b). The study of 1,707 residents assessed respiratory symptoms for 1,168 person-years of observation. One or more symptoms occurred at least one-quarter of the time among 22 percent of subjects in the study and at least half the time among 6.5 percent. The symptoms that were most often reported included common cold and rhinitis (8 percent of all person-days each), cough (5 percent), headache (2.45 percent), eye irritation (1.8 percent), and chest whistling/wheezing (0.77 percent). The investigator in this study has speculated that reported colds and other infections could have been mislabeled and that an unknown portion of these symptoms could be attributable to allergic diseases.
Data from the NHIS (NCHS, 1986) indicate that in 1985 there were 87.1 acute respiratory conditions per 100 persons. Of these, 46.4 percent were categorized as influenza, 35 percent as common colds, and 11.7 percent as other acute respiratory illnesses. The remainder were labeled as acute bronchitis (3 percent), pneumonia (1 percent), and other (2 percent).
As outlined in this chapter, allergic disease constitutes a substantial public health problem in the United States. Data on its exact magnitude and dimensions, however, are incomplete, or lacking, in many cases. Better data regarding the incidence, prevalence, attributable fraction, and cost of allergic diseases are essential to the development of effective programs of prevention and control. Accurate determinations of the magnitude and dimensions