Tracy J M, Demain J G, Quinn J M, Hoffman D R, Goetz D W, Freeman T M
Wilford Hall Medical Center, Lackland Air Force Base, TX 78236-5300, USA.
J Allergy Clin Immunol. 1995 Apr;95(4):824-8. doi: 10.1016/s0091-6749(95)70125-7.
Imported fire ants (IFA) are a common cause of insect venom hypersensitivity in the southeastern United States. The purpose of this study was to determine the sting attack rate and development of specific IgE in an unsensitized population.
Study participants consisted of 137 medical students with limited exposure to IFA-endemic areas who were temporarily training in San Antonio, Tex. Subjects were surveyed for prior IFA exposure with a questionnaire, and IFA-specific IgE was evaluated with RAST and intradermal skin testing. Evaluations were performed on arrival and reported at departure from the endemic area 3 weeks later.
One hundred seven subjects completed the study. Field stings were reported in 55 subjects, resulting in a sting attack rate of 51%. In these 55 subjects 53 (96%) reported a pustule or a small local reaction at the sting site, one (2%) reported an isolated large local reaction, and none reported a systemic reaction. At the 3-week follow-up skin test and RAST conversions occurred in seven subjects (13%) and in one subject (1.8%), respectively.
Even brief exposures to IFA-endemic areas result in significant sting rates and concurrent rapid development of IFA-specific IgE in 16% of stung subjects.
外来火蚁是美国东南部昆虫毒液超敏反应的常见病因。本研究旨在确定未致敏人群中的叮咬发生率以及特异性IgE的产生情况。
研究参与者包括137名在得克萨斯州圣安东尼奥临时培训、接触外来火蚁流行地区较少的医学生。通过问卷调查受试者既往接触外来火蚁的情况，并用放射变应原吸附试验（RAST）和皮内皮肤试验评估外来火蚁特异性IgE。在到达时进行评估，并在3周后离开流行地区时报告结果。
107名受试者完成了研究。55名受试者报告在野外被叮咬，叮咬发生率为51%。在这55名受试者中，53名（96%）报告叮咬部位出现脓疱或轻微局部反应，1名（2%）报告孤立的严重局部反应，无人报告全身反应。在3周的随访中，7名受试者（13%）皮肤试验结果发生转换，1名受试者（1.8%）RAST结果发生转换。
即使是短暂接触外来火蚁流行地区，叮咬发生率也很高，并且16%被叮咬的受试者会同时迅速产生外来火蚁特异性IgE。
