[An epidemiologic study on prevalence of allergen-specific IgE antibodies in school children living in rural area of Saitama Prefecture, Japan].
BACKGROUND
In order to estimate the sensitization to inhalant allergen in childhood, prevalence of allergen-specific IgE antibodies was retrospectively surveyed on sera from school children aged from 9 to 15 living in rural area of Saitama prefecture, Japan, in 2001 and five years ago from 2001 (1996).


METHODS
Allergen-specific IgE antibodies against Japanese cedar pollen (JCP), ragweed, sweet vernal grass, Dermatophagoides pteronyssinus (Dp), house dust (HD) and cat dander were examined on sera from 79 school children aged from 9 to 11 (group A) and 119 school children aged from 12 to 15 (group B) collected in 2001, and sera from 117 school children aged from 9 to 11 and 56 school children aged from 12 to 15 collected in 1996. Furthermore, a questionnaire survey about diagnosis of any allergic diseases and symptoms associated with the diseases was conducted on the same subjects in 2001.


RESULTS
On the survey from school children, group A and B, collected in 2001, percentage of positive cases for allergen-specific IgE antibodies against any of 6 allergens were 49 in both of the groups for JCP, 10 and 12 for ragweed, 18 and 19 for sweet vernal grass, 39 in both of the groups for Dp, 42 in both of the groups for HD, 23 and 14 for cat dander, respectively. On the survey from school children collected in 1996, there is no significant difference from the percentage of positive cases for allergen-specific IgE antibodies against each allergen in 2001. Among the subjects followed-up on the survey in both of the years, the percentage of positive cases for allergen-specific IgE antibodies against each of six allergens on the survey in 2001 increased as compared with those in 1996. As a result of questionnaire survey in 2001, percentage (70: group A, 89: group B) of positive cases for allergen-specific IgE antibodies against any 6 allergens in the subjects with any symptoms associated with allergic diseases, but not diagnosed, was significantly higher than the percentage (34: group A, 48: group B) of that in the subjects without any symptoms associated with the diseases.


CONCLUSIONS
Further prospective study is required to clarify a cause of allergic diseases in childhood, and it should be taken precautionary measures during childhood against sensitization with inhalant allergen to prevent allergic diseases in surveyed area.
Ikushima
Masako
M
Saitama Institute of Public Health. a0189434@pref.saitama.lg.jp
Takaoka
Masatoshi
M
Kawahashi
Sachie
S
Tanno
Sakiko
S
D000485:Allergens / Q000276:immunology*; D000906:Antibodies / Q000097:blood*; D002648:Child; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007564:Japan; D008297:Male; D015995:Prevalence; D012189:Retrospective Studies; D012424:Rural Population
D000485:Allergens; D000906:Antibodies; D007073:Immunoglobulin E