State wildlife experts are on the lookout for a new virus impacting native rabbit and hare populations. Following an initial outbreak in New Mexico in March 2020, the virus causing rabbit hemorrhagic disease is considered stable-endemic in Arizona, Colorado, California, Idaho, Montana, Nevada, New Mexico, Oregon, Texas, Utah and Wyoming.
Rabbit hemorrhagic disease virus serotypes 2 (RHDV2) can persist in the environment and can be spread from rabbit to rabbit, by predators, insects and even by vehicle traffic, impacting populations in new areas. While the virus is not currently in Iowa, it has been confirmed in domestic rabbits in Minnesota and South Dakota, and in the wild rabbit population in eastern Colorado and northern Texas.
The disease has had a significant impact on native populations, as well as feral and domestic rabbits which are also susceptible. Iowa State Wildlife Veterinarian Dr. Rachel Ruden said keeping this virus on Iowans’ radar is key to minimizing its impact should it show up here.
“Eastern cottontails are such common yard visitors, we sometimes forget that they can get sick too and those reports are important,” Dr. Ruden said. “Infected animals die quickly, sometimes with blood or red-tinged foam visible around the nose, but often with no signs of illness. If you find a dead rabbit, and especially a cluster of dead rabbits, please reach out as early detection is key to stemming a larger outbreak.”
While Iowa’s eastern cottontail population is expected to survive a disease incursion, there is some concern regarding Iowa’s declining jackrabbit population, which is concentrated in certain parts of the state and so might have difficulty rebounding.
The recently emerged strain, RHDV2, was first detected in Europe in 2010. It is not related to epizootic hemorrhagic disease that can cause mortality in deer or COVID-19, the current cause of the human pandemic. It does not pose a risk to people and is not known to affect other animals. More information about the disease is available online at https://www.aphis.usda.gov/publications/animal_health/fs-rhdv2.pdf and guidance specific to hunters and outdoor recreationalists is available at https://www.fishwildlife.org/application/files/9315/9662/4394/AFWA_Rabbit_Hemorrhagic_DiseaseGuidance_6-29-2020.docx.
A vaccine is now available for emergency use through a licensed veterinarian to protect domestic rabbits. Iowans can learn more by going to https://iowaagriculture.gov/news/idals-authorizes-use-rhdv2-vaccine-1082021