2026-11-12 テキサスA&M大学
テキサスA&M大学AgriLife Researchの研究チームは、家畜や野生動物に深刻な被害を与える新世界ラセンウジバエ（Cochliomyia hominivorax）の駆除に向け、電子ビーム（eBeam）を利用した高速・非放射性の不妊化技術を開発した。従来の不妊虫放飼法（SIT）では、コバルト60などの放射性同位体を用いて雄の蛹を不妊化していたが、放射性物質の管理や安全性、設備コストが課題となっていた。研究チームは、電子ビームの照射量を変えながら蛹を処理し、羽化後の成虫について生殖能力、飛翔能力、生存状況などを検証した。その結果、繁殖能力だけを失わせ、飛翔や正常な生活環を維持できることを確認した。さらに、従来は数分かかっていた処理を数秒に短縮し、一度に数千匹の蛹を処理できる可能性も示した。本技術は放射性物質を使用しないため、設備の安全性や運用コストの改善が期待される。今後は照射条件の最適化と実用規模での検証を進め、家畜産業や野生動物を保護する害虫防除技術への展開を目指す。
Electron beam technology has shown strong potential for application in the Sterile Insect Technique, or SIT, against New World screwworm flies. The technology could speed the sterilization process and remove the need for radioactive materials to be stored at SIT facilities. Credit: Jason Nitsch/Texas A&M AgriLife
＜関連情報＞
- https://stories.tamu.edu/news/2026/11/12/researchers-advance-faster-safer-sterilization-technique-in-battle-against-new-world-screwworm/
- https://www.aphis.usda.gov/animals/animal-health/livestock-and-poultry-disease/usda-continues-lead-aggressive-national-nws
米国農務省、新世界ラセンウジバエ（New World Screwworm）の侵入阻止に向けた国家的防除対策を強化（USDA Continues To Lead Aggressive National New World Screwworm (NWS) Response）
U.S. Department of Agriculture（USDA）
Animal and Plant Health Inspection Service（APHIS）2026-07-31
USDA：New World Screwworm Response
Tii-summary
新世界ラセンウジバエ（New World Screwworm：NWS）は、家畜や野生動物に寄生し、生きた動物の組織を食害する深刻な害虫であり、米国では畜産業や公衆衛生への脅威となっている。米国農務省（USDA）は、メキシコおよび中米からの侵入拡大を防ぐため、連邦政府機関と国際機関が連携する国家的防除計画を推進している。対策の柱は、①メキシコとの国境を越えた監視・防除協力、②トラップやドローン、カメラを活用した監視体制の強化、③農家や獣医師などへの情報提供、④不妊虫放飼法による個体群抑制、⑤新たな検出・駆除技術の開発である。USDAはメキシコとテキサス州で週当たり約1億匹の不妊化したハエを放飼しており、テキサス州には週8000万匹以上を散布する施設を整備した。さらに、南テキサス州では最大週3億匹の生産能力を持つ不妊虫生産施設の建設を進めている。また、電子線照射や次世代X線照射による不妊化技術の実証、新たな雄のみを生産する系統の開発にも取り組んでいる。約1億500万ドルを投じる40件の研究開発プロジェクトも開始されており、監視・診断・防除技術を総合的に強化することで、害虫の根絶と米国の畜産・食料供給の保護を目指している。
The New World screwworm (NWS) is a serious parasitic pest whose larvae feed on the living tissue of warm-blooded animals, posing a significant threat to livestock, wildlife, and public health. The US Department of Agriculture (USDA) is leading a nationwide response to prevent its spread into the United States through coordinated efforts with Mexico, Central American partners, and multiple federal agencies. The strategy comprises five main areas: cross-border cooperation with Mexico, enhanced surveillance and detection, public awareness and education, sterile insect releases, and innovation in detection and eradication technologies. USDA is currently dispersing approximately 100 million sterile flies per week across Mexico and Texas, while a newly completed facility in Texas supports the deployment of more than 80 million sterile flies weekly. A further production facility in southern Texas is under construction, with an initial capacity of up to 100 million sterile flies per week and planned expansion to 300 million by late 2028. Research initiatives include testing electron-beam and next-generation X-ray sterilization technologies, as well as developing a male-only screwworm strain to increase the operational supply of sterile insects. In addition, approximately $105 million has been allocated to 40 research and development projects focused on detection, control, and eradication. Through integrated surveillance, international cooperation, and advanced biological control technologies, the initiative aims to eradicate the pest and safeguard livestock production and food security.
The New World screwworm (NWS) is a serious parasitic pest whose larvae feed on the living tissue of warm-blooded animals, posing a significant threat to livestock, wildlife, and public health. The US Department of Agriculture (USDA) is leading a nationwide response to prevent its spread into the United States through coordinated efforts with Mexico, Central American partners, and multiple federal agencies. The strategy comprises five main areas: cross-border cooperation with Mexico, enhanced surveillance and detection, public awareness and education, sterile insect releases, and innovation in detection and eradication technologies. USDA is currently dispersing approximately 100 million sterile flies per week across Mexico and Texas, while a newly completed facility in Texas supports the deployment of more than 80 million sterile flies weekly. A further production facility in southern Texas is under construction, with an initial capacity of up to 100 million sterile flies per week and planned expansion to 300 million by late 2028. Research initiatives include testing electron-beam and next-generation X-ray sterilization technologies, as well as developing a male-only screwworm strain to increase the operational supply of sterile insects. In addition, approximately $105 million has been allocated to 40 research and development projects focused on detection, control, and eradication. Through integrated surveillance, international cooperation, and advanced biological control technologies, the initiative aims to eradicate the pest and safeguard livestock production and food security.
注：本資料は査読付き学術論文ではなく、USDAによる防疫政策・技術開発の進捗報告です。掲載内容は2026年7月31日更新の公式情報に基づきます。
