Department of Public Health and Clinical Medicine, Epidemiology and Global Health Unit, Umeå University, Umeå, Västerbotten, Sweden; Institute of Public Health, University of Heidelberg, Heidelberg, Germany.
J Travel Med. 2015 May-Jun;22(3):186-93. doi: 10.1111/jtm.12192. Epub 2015 Mar 10.
Southern Europe is increasingly at risk for dengue emergence, given the seasonal presence of relevant mosquito vectors and suitable climatic conditions. For example, Aedes mosquitoes, the main vector for both dengue and chikungunya, are abundant in Italy, and Italy experienced the first ever outbreak of chikungunya in Europe in 2007. We set out to estimate the extent of dengue virus importations into Italy via air travelers.
We attempted to quantify the number of dengue virus importations based on modeling of published estimates on dengue incidence in the countries of disembarkation and analysis of data on comprehensive air travel from these countries into Italy's largest international airport in Rome.
From 2005 to 2012, more than 7.3 million air passengers departing from 100 dengue-endemic countries arrived in Rome. Our Importation Model, which included air traveler volume, estimated the incidence of dengue infections in the countries of disembarkation, and the probability of infection coinciding with travel accounted for an average of 2,320 (1,621-3,255) imported dengue virus infections per year, of which 572 (381-858) were "apparent" dengue infections and 1,747 (1,240-2,397) "inapparent."
Between 2005 and 2012, we found an increasing trend of dengue virus infections imported into Rome via air travel, which may pose a potential threat for future emergence of dengue in Italy, given that the reoccurring pattern of peak importations corresponds seasonally with periods of relevant mosquito vector activity. The observed increasing annual trends of dengue importation and the consistent peaks in late summer underpin the urgency in determining the threshold levels for the vector and infected human populations that could facilitate novel autochthonous transmission of dengue in Europe.
由于相关蚊虫媒介的季节性存在和适宜的气候条件，南欧越来越面临登革热的出现风险。例如，意大利存在大量的伊蚊，这是登革热和基孔肯雅热的主要传播媒介，意大利在 2007 年首次经历了欧洲的基孔肯雅热疫情爆发。我们旨在估计通过航空旅客输入意大利的登革热病毒的程度。
我们试图通过建模在登革热发病率较高的国家的已有估计和分析这些国家到意大利最大的国际机场罗马的全面航空旅行数据，量化登革热病毒的输入数量。
2005 年至 2012 年，有超过 730 万从 100 个登革热流行国家出发的航空旅客抵达罗马。我们的输入模型包括航空旅客数量、登革热发病率较高的国家的发病率以及感染与旅行重合的可能性，估计每年平均输入 2320 例（1621-3255 例）登革热病毒感染，其中 572 例（381-858 例）为“显性”登革热感染，1747 例（1240-2397 例）为“隐性”登革热感染。
2005 年至 2012 年，我们发现通过航空旅行输入罗马的登革热病毒感染呈上升趋势，这可能对意大利未来的登革热疫情构成潜在威胁，因为相关蚊虫媒介活动的季节性与输入高峰期的重复模式相对应。观察到的登革热输入量的年增长率以及夏季末的持续高峰表明，确定有助于欧洲新的本地传播的媒介和感染人群的阈值水平的紧迫性。
