Abstract
BackgroundIn summer 2014, an autochthonous outbreak of dengue occurred in Tokyo, Japan, in which Yoyogi Park acted as the focal area of transmission. Recognizing the outbreak, concerted efforts were made to control viral spread, which included mosquito control, public announcement of the outbreak, and a total ban on entering the park. We sought to assess the effectiveness of these control measures.Methodology/Principal findingsWe used a mathematical model to describe the transmission dynamics. Using dates of exposure and illness onset, we categorized cases into three groups according to the availability of these datasets. The infection process was parametrically modeled by generation, and convolution of the infection process and the incubation period was fitted to the data. By estimating the effective reproduction number, we determined that the effect of dengue risk communication together with mosquito control from 28 August 2014 was insufficiently large to lower the reproduction number to below 1. However, once Yoyogi Park was closed on 4 September, the value of the effective reproduction number began to fall below 1, and the associated relative reduction in the effective reproduction number was estimated to be 20%–60%. The mean incubation period was an estimated 5.8 days.Conclusions/SignificanceRegardless of the assumed number of generations of cases, the combined effect of mosquito control, risk communication, and park closure appeared to be successful in interrupting the chain of dengue transmission in Tokyo.
Highlights
Dengue fever is a vector-borne viral disease, caused by dengue virus (DENV) and transmitted by Aedes aegypti and Aedes albopictus [1,2,3,4]
The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript
We developed a novel method to directly parameterize the incidence of infection, by convoluting the incidence of infection with the incubation period, allowing us to precisely incorporate the timing of interventions and observe their effect on virus transmission dynamics on a given day
Summary
Dengue fever is a vector-borne viral disease, caused by dengue virus (DENV) and transmitted by Aedes aegypti and Aedes albopictus [1,2,3,4]. Following primary infection with one serotype, infected and recovered individuals remain prone to secondary infection with other serotypes that could induce a clinically severe form of infection, including dengue hemorrhagic fever and dengue shock syndrome [6,7]. DENV infections are seen mostly in tropical and subtropical countries, but nonendemic areas in temperate regions are at risk [5,8,9,10,11], owing partly to the changing ecological dynamics of vector abundance, perhaps induced by global warming [12] and an increased volume of international travel [13]. We sought to assess the effectiveness of these control measures
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
