Naomi Nakamura1, Yuzo Arima, Tomoe Shimada, Tamano Matsui, Yuki Tada, Nobuhiko Okabe. 1. Field Epidemiology Training Program, National Institute of Infectious Diseases, Tokyo, Japan . ; Division of Quarantine and Sanitation, Chubu Airport Quarantine Branch, Nagoya Quarantine Station, Aichi, Japan .
Abstract
INTRODUCTION: Dengue continues to be a global public health concern. In Japan, although dengue cases are currently seen only among travellers returning from endemic areas, the number of reported cases is rising according to the national case-based surveillance system. We evaluated the characteristics of dengue cases imported into Japan and the relationship between the incidence of infection and season of travel to popular destinations. METHODS: Dengue cases reported to the national surveillance system were retrospectively examined. The number of reported cases per number of Japanese travellers to a dengue-endemic country was calculated to estimate the country-specific incidence of imported dengue virus infection. The incidence of dengue infection among Japanese travellers was compared between dengue high season and low season in each country using relative risk (RR) and associated 95% confidence intervals (CI). RESULTS: Among 540 Japanese residents who were reported as dengue cases from 2006 to 2010, the majority had travelled to Indonesia, India, the Philippines and Thailand. The RR of dengue infection among Japanese travellers during dengue high season versus low season was 4.92 (95% CI: 3.01-8.04) for the Philippines, 2.76 (95% CI: 1.67-4.54) for Thailand and 0.37 (95% CI: 0.15-0.92) for Indonesia. DISCUSSION: Overall, higher incidence of imported cases appeared to be related to historic dengue high seasons. Travellers planning to visit dengue-endemic countries should be aware of historic dengue seasonality and the current dengue situation.
INTRODUCTION: Dengue continues to be a global public health concern. In Japan, although dengue cases are currently seen only among travellers returning from endemic areas, the number of reported cases is rising according to the national case-based surveillance system. We evaluated the characteristics of dengue cases imported into Japan and the relationship between the incidence of infection and season of travel to popular destinations. METHODS: Dengue cases reported to the national surveillance system were retrospectively examined. The number of reported cases per number of Japanese travellers to a dengue-endemic country was calculated to estimate the country-specific incidence of imported dengue virus infection. The incidence of dengue infection among Japanese travellers was compared between dengue high season and low season in each country using relative risk (RR) and associated 95% confidence intervals (CI). RESULTS: Among 540 Japanese residents who were reported as dengue cases from 2006 to 2010, the majority had travelled to Indonesia, India, the Philippines and Thailand. The RR of dengue infection among Japanese travellers during dengue high season versus low season was 4.92 (95% CI: 3.01-8.04) for the Philippines, 2.76 (95% CI: 1.67-4.54) for Thailand and 0.37 (95% CI: 0.15-0.92) for Indonesia. DISCUSSION: Overall, higher incidence of imported cases appeared to be related to historic dengue high seasons. Travellers planning to visit dengue-endemic countries should be aware of historic dengue seasonality and the current dengue situation.
Authors: G La Ruche; Y Souarès; A Armengaud; F Peloux-Petiot; P Delaunay; P Desprès; A Lenglet; F Jourdain; I Leparc-Goffart; F Charlet; L Ollier; K Mantey; T Mollet; J P Fournier; R Torrents; K Leitmeyer; P Hilairet; H Zeller; W Van Bortel; D Dejour-Salamanca; M Grandadam; M Gastellu-Etchegorry Journal: Euro Surveill Date: 2010-09-30
Authors: J N Hanna; S A Ritchie; A D Merritt; A F van den Hurk; D A Phillips; I L Serafin; R E Norton; W J McBride; F V Gleeson; M Poidinger Journal: Med J Aust Date: 1998-03-02 Impact factor: 7.738
Authors: Rashedul Islam; Mohammed Salahuddin; Md Salahuddin Ayubi; Tahmina Hossain; Apurba Majumder; Andrew W Taylor-Robinson; Abdullah Mahmud-Al-Rafat Journal: Virol Sin Date: 2015-10-20 Impact factor: 4.327