中国でヒト感染を引き起こすH7N9インフルエンザウイルスの起源と発生源
Tommy Tsan-Yuk Lam1, Jia Wang, Yongyi Shen
1Joint Influenza Research Centre (SUMC/HKU), Shantou University Medical College, Shantou 515041, China.
Nature
|August 23, 2013
まとめ
新しいH7N9鳥インフルエンザウイルスは,中国の家禽のH7とH9N2ウイルスの再分類から発生した. 鶏で発生するこの再分類イベントは,現在のアウトブレイクにつながり,進行中のパンデミックリスクをもたらしています.
科学分野:
- ウイルス学 ウイルス学 ウイルス学
- エピデミオロジー エピデミオロジー
- 進化生物学の進化生物学について
背景:
- 新型H7N9インフルエンザAウイルスは,2013年から中国で重大なヒト感染と死亡を引き起こした.
- H7N9疫病の起源と起源は不明であり,事前分析では,鳥インフルエンザウイルスの再分類が示唆されている.
研究 の 目的:
- H7N9インフルエンザAウイルス発生の発生源集団と条件を調査する.
- H7型インフルエンザウイルスの進化経路と種間感染ダイナミクスを理解する.
主な方法:
- 鳥類の集団を積極的に監視する.
- 歴史的なウイルスアーカイブのスクリーニング.
- インフルエンザウイルスのゲノムに関する系統遺伝学的および進化的分析.
主要な成果:
- H7ウイルスは,中国で少なくとも2回,家禽から鶏に伝染していることが判明しました.
- H7ウイルスと動物性H9N2ウイルスの再分類により,H7N9流行の系統と新しいH7N7系統が生まれた.
- H7N9系は,ヒトの感染の可能性のある源として特定された,生きている家禽の市場で流行しており,関連するH7N7ウイルスは実験的に哺乳類の感染性を実証しました.
結論:
- H7N9流行の系統は,主にアヒルとニワトリを含む中国の家禽の再分類イベントから発生しました.
- 生きた家禽の市場は,H7N9のヒトへの感染の重要なインターフェースとして機能しています.
- H7N7を含む関連するH7ウイルスは,哺乳類に感染する能力とさらなる進化の可能性のために,現在のアウトブレイクを超えて潜在的な脅威をもたらす.
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