Risk Factors for Allergy due to the Two-Spotted Spider Mite <i>(Tetranychus urticae)</i> among Table Grape Farm Workers

Abstract

Background: Recent studies have reported an increased prevalence of respiratory symptoms among farm workers. The aim of this study was to identify risk factors associated with spider mite allergy among table grape farm workers. Methods: A cross-sectional study of 207 workers in table grape farms was conducted. Skin prick tests used extracts of 8 common aeroallergens, grape mould (Botrytis cinerea) and Tetranychus urticae. Specific IgE to T. urticae was quantified using ImmunoCAP (Phadia). Erythrocyte cholinesterase levels were determined using the Test-mate ChE Cholinesterase Test System (model 460). Results: The average duration of employment of workers was 10 years and 12% were pesticide crop sprayers. Work-related wheeze (26%), ocular-nasal (24%) and urticaria/skin symptoms (14%) were more prevalent in the orchards. The prevalence of sensitization (skin prick test) was highest to T. urticae (22%) followed by house dust mite (16%), with 25% being atopic. The prevalence of allergy to T. urticae (skin reactivity and work-related symptoms) was 9.5%, with respiratory allergy (6%) more common than skin allergy (3%). Work-related ocular-nasal (OR = 4.9) and skin (OR = 3.7) symptoms were more commonly reported by pesticide crop sprayers. Workers with T. urticae-allergic rhino-conjunctivitis and probable asthma were more likely to be atopic, spray pesticides and have low (<30 U/g hemoglobin) erythrocyte cholinesterase levels. Conclusions: This study demonstrated that spider mite, T. urticae, is an important outdoor allergen among table grape farm workers. The increased risk of spider mite allergy appears to be related to high pesticide exposure among crop sprayers.

Mite and cockroach sensitisation in patients with allergic rhinitis in the Free State

“…25 In contrast, we found a fair to good agreement between sensitisation to T. urticae and sensitisation to the house-dust mites and A. siro, and a fair agreement between sensitisation to any of the house-dust mites and sensitisation to the storage mites B. tropicalis and A. siro but not the other storage mites. Although spider mite-derived extracts contain allergens that are shared in common with domestic mites, major allergens derived from spider mites are unique in terms of cross-reactivity with domestic mites.…”

“…23,24 They have emerged as an important allergen in agricultural workers dealing with fruit trees or working in greenhouses as well as in the surrounding populations, the main symptoms associated with sensitisation and exposure to Tetranychidae mites being rhinoconjunctivitis and asthma. 17,23,25 Jeebhay et al found that T. urticae could be responsible for work-related asthma symptoms in their study of table grape farm workers in the Western Cape and that skin reactivity to T. urticae was more common than to housedust mite. 25 A Korean study found that these mites might be common sensitising allergens in the general adult population and that they may play a role in the manifestation of rhinitis and asthma symptoms.…”

“…17,23,25 Jeebhay et al found that T. urticae could be responsible for work-related asthma symptoms in their study of table grape farm workers in the Western Cape and that skin reactivity to T. urticae was more common than to housedust mite. 25 A Korean study found that these mites might be common sensitising allergens in the general adult population and that they may play a role in the manifestation of rhinitis and asthma symptoms. 26 T. urticae has a worldwide distribution and is a pest on deciduous trees, fruit trees, ornamental trees, fields, strawberries, gooseberries and most vegetables.…”

Shellfish allergy

“…This seemingly frequently encountered cross-reactivity is probably due to tropomyosin and may have significant clinical implications. This has been shown particularly for shellfish allergens and tropomyosins from insects and mites, which are all part of the phylum arthropod [81,82].…”

“…This seemingly frequently encountered cross‐reactivity is probably due to tropomyosin and may have significant clinical implications. This has been shown particularly for shellfish allergens and tropomyosins from insects and mites, which are all part of the phylum arthropod [81, 82]. A recent study demonstrated sensitization to shrimp tropomyosin in orthodox Jews, who are prohibited by religious dietary laws from eating shellfish, which could be indicative of sensitization to tropomyosin from non‐crustacean, such as HDM and cockroaches, via the inhalation route [83].…”