Spread of rabbit hemorrhagic disease virus 2 (rhdv2) in wild and domestic lagomorphs in the western United States

Abstract

Rabbit Hemorrhagic Disease Virus 2 (RHDV2) affects all lagomorphs including domestic and wild rabbits, hares, and pikas. The V2 serotype of the RHD virus first appeared in France in 2010 and as of 2020 has become endemic in North America, particularly in the western United States. RHDV2 and its predecessor RHDV1 have had devastating impacts on wild rabbit populations due to high virulence and lethality, often killing hosts within 72 hours of infection. This analysis focuses on understanding factors related to spread of the virus in the western United States. I utilize data from the USDA APHIS RHDV2 ArcGIS web map to document the spread of confirmed cases in wild, domestic, and feral rabbits in the western states over the last two years. I also analyze the regulatory frameworks and permitting for the RHDV2 vaccine, in addition to an identification of key stakeholders and analysis of risk communication on the virus. My investigation of this virus suggested that RHDV2 poses a greater risk to lagomorph species than RHDV1 due to higher transmission rates and virulence, the ability to infect young rabbits before maturity, and the ability to overcome RHDV1 immunity. Mapping completed for my analysis indicates that both wild and domestic cases spread rapidly throughout the western states in 2020 and 2021, particularly during peak breeding times, with confirmed cases largely centered in California and Arizona and near population centers. In limiting the spread of the virus, current policies and laws need to be more thorough. Monitoring the spread of this disease is difficult due to government and fiscal constraints. A wide range of interested stakeholders from commercial, government, and public sectors are involved in this issue. Without a joint effort focused on obtaining and understanding the necessary data, and considering the limitations of current laws, it has proven difficult to control the spread of RHDV2 and the associated impacts on stakeholders. Increased monitoring by government organizations and citizen scientists can provide necessary data to determine the severity of the problem, and inform measures required to mitigate the impact of RHDV2 on lagomorph populations in the United States.