U.S. South Identified as Highest Risk Region for North American Japanese Encephalitis Introduction

A Swine Health Information Center funded risk assessment has identified the U.S. south as the highest risk region for the potential introduction of Japanese encephalitis virus into North America.

Japanese encephalitis virus, a mosquito born pathogen, has been identified as a transboundary emerging disease risk for the North American pork industry.
Researchers with Kansas State University have conducted a risk assessment for JEV emergence into seven U.S. regions.

SHIC Executive Director Dr. Megan Niederwerder says various pathways of entry were considered including eggs or larvae on imported goods, infected adult mosquitos transported in aircraft, ships or shipping containers and infected migrating birds.

Quote-Dr. Megan Niederwerder-Swine Health Information Center:

What these investigators found was that the risk of JEV introduction through infected adult mosquitos in cargo ships as well as eggs and larvae in tires was moderate with the highest risk regions being in the south, the west and the northeast.The overall risk however that they found was the highest for the south region and that this region should be prioritised for JEV preparedness as it had the highest risk of JEV introduction and impact.

Some of the risk factors that were considered include the availability of competent insect vectors.You can think about the habitat that potentially support those insect vectors throughout various seasons.They considered the susceptible maintenance avian hosts as well as the consideration of populations for susceptible feral swine as well as domestic commercial swine.

They also considered the travel and trade that occurred in various regions of the U.S. from JEV affected countries based on the number of seaports and airports that were receiving those goods as well as looking at the climate and environmental conditions and comparing those to regions that support JEV in an endemic capacity.

Full details of this study are highlighted as part of SHIC's April eNewsletter which can be found at swinehealth.org.