Dengue risk mapping and immunization strategy in Japan

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K22765
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 58:Society medicine, nursing, and related fields
• Research Institution: National Institute of Infectious Diseases
• Principal Investigator: Suzuki Motoi 国立感染症研究所, 感染症疫学センター, センター長 (60444874)
• Co-Investigator(Kenkyū-buntansha): 吉田 レイミント 長崎大学, 熱帯医学研究所, 教授 (90432963)
• Project Period (FY): 2019-06-28 – 2023-03-31
• Keywords: デング熱 / 輸入感染症

Outline of Final Research Achievements

The aim of this study was to quantitatively evaluate the importation risk of dengue fever in Japan and assess its correlation with the epidemic situation in endemic areas, as well as the impact of the COVID-19 pandemic. The importation risk of dengue fever cases in Japan from 2016 to 2019 was 6.5 per one million arrivals. The cross-correlation function with the reported cases in endemic areas showed the Philippines to have the highest correlation, peaking at a lag of three weeks. Singapore had the next highest correlation, peaking at a lag of six weeks. No significant correlation was found for the Federal District of Brazil. After the onset of the pandemic, the rate ratio of reported cases was 2.0 (95% CI: 0.9-3.8), and the rate difference was 6.4 per one million arrivals (－2.0-14.8).

Free Research Field

感染症疫学

Academic Significance and Societal Importance of the Research Achievements

研究結果より、新型コロナウイルス感染症のパンデミック以前においては、特に東南アジア地域における流行状況が日本の輸入デング症例の推移に大きく影響していたことが示唆された。これは渡航者数と地域の流行状況によって規定されていると考えられる。パンデミック以降は報告数の減少が見られたが、到着あたり報告数については明らかな変化はなかった。このことから2022年後半以降の国際的な人の移動の再活性化に伴って、輸入デング症例の増加が予想される。