Details

Autor(en) / Beteiligte

• Sakai, Takatsugu
• Suzuki, Hiroshi
• Sasaki, Asami
• Saito, Reiko
• Tanabe, Naohito
• Taniguchi, Kiyosu

Titel

Geographic and temporal trends in influenzalike illness, Japan, 1992-1999

Ist Teil von

• Emerging infectious diseases, 2004-10, Vol.10 (10), p.1822-1826

Ort / Verlag

United States: U.S. National Center for Infectious Diseases

Erscheinungsjahr

2004

Link zum Volltext

Quelle

Elektronische Zeitschriftenbibliothek - Frei zugängliche E-Journals

Beschreibungen/Notizen

• From 1992 to 1999, we analyzed >2.5 million cases of influenzalike illness (ILI). Nationwide influenza epidemics generally lasted 3-4 months in winter. Kriging analysis, which illustrates geographic movement, showed that the starting areas of peak ILI activity were mostly found in western Japan. Two spreading patterns, monotonous and multitonous, were observed. Monotonous patterns in two seasons featured peak ILI activity that covered all of Japan within 3 to 5 weeks in larger epidemics with new antigenic variants of A/H3N2. Multitonous patterns, observed in the other five seasons, featured peak ILI activity within 12 to 15 weeks in small epidemics without new variants. Applying the kriging method allowed better visualization and understanding of spatiotemporal trends in seasonal ILI activity. This method will likely be an important tool for future influenza surveillance in Japan.