Evidence of allergic hypersensitivity to chironomid midges in an English village community.
Some chironomid (non-biting) midges contain potent human allergens, principally in the form of insect haemoglobins. In view of previously demonstrated immunological cross-reactivity between some different midge species, the possible role of British midges in allergic disease was studied. The chosen site, Farmoor near Oxford, is a village that has been subject to several annual nuisance midge swarms since the construction of an adjacent water-supply reservoir in 1964, which was extended in 1975. The incidence and severity of hypersensitivity in the community was assessed by questionnaire survey, skin-prick testing, radio-allergosorbent tests (RAST) and RAST inhibition, and enzyme-linked immunosorbent assays (ELISA) and ELISA inhibition, using extracts of locally caught adult midges (Tanytarsus sylvaticus, T. bathophilus and Chironomus anthracinus) and laboratory cultured larvae (C. riparius). These tests revealed a low but significant level of midge-related hypersensitivity with skin-prick results showing seasonal fluctuations, but this seasonality was not confirmed with an IgE RAST. A correlation between IgE levels and relevant symptoms was found (P less than 0.01) using RAST, but not between IgE and skin-test results. Enzyme-linked immunosorbent assay results did not correlate with any other parameter measured. The incidence and severity of allergic reactions to the midges tested in this community was low.
McHugh
S M
SM
Department of Biology, Royal Holloway and Bedford New College, Surrey, U.K.
Credland
P F
PF
Tee
R D
RD
Cranston
P S
PS
D000328:Adult; D000818:Animals; D002683:Chironomidae / Q000276:immunology*; D004175:Diptera / Q000276:immunology*; D004739:England; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D011852:Radioallergosorbent Test; D012130:Respiratory Hypersensitivity / Q000276:immunology*; D012621:Seasons; D012882:Skin Tests
D007073:Immunoglobulin E