Wiley Handbook of Science and Technology for Homeland Security, 4 Volume Set

FOREIGN DENGUE VIRUS PRESENTS A LOW RISK TO U.S. HOMELAND

TERRY CARPENTER, KATHRYN L. CLARK, R. KEVIN HANSON, AND MICHAEL SARDELIS

National Center for Medical Intelligence, Frederick, Maryland

1 INTRODUCTION

Widespread dengue virus transmission in the continental United States is very unlikely. Media reporting in early 2008 [1, 2] speculating that the dengue virus may soon be introduced and spread nationwide, as West Nile virus (WNV) did previously, have grossly overstated the threat. Once WNV was imported into the United States, many factors facilitated its spread and long-term establishment, which do not apply to dengue virus [3]. While sustained dengue virus transmission is unlikely, isolated cases or small case clusters of local transmission resulting from sporadic introduction by infected travelers will continue to occur in limited areas of the country where competent mosquito vectors are present. Such cases will likely be identified and contained by effective US public health responses.

2 BACKGROUND OF DENGUE AND WEST NILE VIRUSES

2.1 Worldwide Dengue Distribution

Dengue fever is transmitted at high levels year round throughout most tropical areas worldwide, including Central and South America, the Caribbean, southern and southeast Asia, the south Pacific, and parts of Africa. An estimated 50–100 million cases occur each year and the geographic distribution of dengue fever continues to expand (Fig. 1) [4].

2.2 History of Dengue Virus in the United States

Dengue fever, which ...