現代の集団における天然の伝播の可能性
1Centre for Applied Microbiology and Research, Porton, Down, Salisbury, Wiltshire SP4 0JG, UK.
Nature
|December 14, 2001
まとめ
天然ウイルスR0 (基本的繁殖数) の推定値は,流行病モデリングを使用して精製されています. 新規の推定では,天然の感染可能性は3.5から6の範囲で,介入前の急速な増加を示している.
科学分野:
- エピデミオロジー エピデミオロジー
- 公共衛生は公衆衛生である.
- 感染症モデリング
背景:
- 麻疹は根絶されていても,実験室でのウイルスの蓄積が残っているため,公衆衛生上のリスクとして残っています.
- R0 (基本的繁殖数) の正確な推定は,天然のリスクを評価するために非常に重要です.
- 以前の天然のR0推定値は不一致 (1.5~>20) であり,社会経済的要因や集団免疫を無視することが多い.
研究 の 目的:
- 疫病モデリングを使用して天花R0のより一貫した推定を導き出します.
- 歴史的な集団と最近のアウトブレイクにおける天然の伝播可能性を評価する.
- 疫病が再発した場合に発生する可能性のある流行経路を予測するためです.
主な方法:
- 小の伝播ダイナミクスをシミュレートするために疫病モデリングを使用しました.
- 20世紀以前の孤立した集団で集団免疫が軽微な歴史データを分析した.
- ワクチン接種レベルと病院での感染を考慮した20世紀のヨーロッパでの散発的な30の流行のデータを調査した.
主要な成果:
- 20世紀以前の集団では,R0は3.5〜6と推定され,最初の指数関数的な症例増加がありました.
- 20世紀のアウトブレイクは,予防接種と病院への影響を考慮して,制御措置の前に同様の伝播レベル (R0: 3.5-6) を示しました.
- ワクチン接種の停止による現在の低集団免疫は,天然が再発した場合,流行の急速な増加を示唆しています.
結論:
- 流行病モデリングは,3.5から6の範囲の天然のより一貫したR0を提供します.
- これらの発見は,集団免疫が欠けている集団における天然の有意な伝染可能性を強調しています.
- の潜在的再発は,公衆衛生の介入が有効になる前に急速に広がる可能性があります.
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