Assessing the Relative Risk of RVF Introduction to the USA via Airline Traffic

A few hundred years ago, just a blink in human history, disease was a complete mystery to mankind. Today, not only do we understand the causes of disease, we can predict how disease will disseminate through a population and where outbreaks will occur. This study aims to quantify the risk of introduction of Rift Valley Fever (RVF) into the USA. RVF is a multi-host mosquito borne disease which was first recognized in Kenya in 1931. Since then, RVF has been detected throughout the continent of Africa and, more recently, in Saudi Arabia. The virus has severe economic impact; it infects several different species of livestock, causing spontaneous abortions of fetuses and severe health detriments, including death, to adults. RVF can also infect humans, potentially causing hemorrhagic fever and death. In this study, we combine information about the life history of hosts, vectors, and pathogens with spatial distribution and movement data in order to quantify the potential of introduction into new areas. Specifically, we will analyze human, livestock, and mosquito movement data from RVF endemic areas in Africa to the USA and assess the relative risk in each mode of introduction, all while overlaying specific scenarios of known human behavior and travel.