Missouri reports summer cases of hemorrhagic disease in white-tailed deer

The Missouri Department of Conservation (MDC) has received reports of hemorrhagic disease (HD) in white-tailed deer during the summer months. HD, caused by Epizootic Hemorrhagic Disease virus and bluetongue virus, is spread by tiny biting flies known as gnats. Infected deer may develop fever, swelling of the head, neck, tongue or eyelids, reduced appetite, weakness and a loss of fear of humans, and can die within 8 to 36 hours.

Diagnosis relies on clinical signs combined with laboratory testing of tissue or blood to differentiate HD from other livestock diseases. There is currently no treatment, vaccine, or wildlife prevention program for the disease.

"Hemorrhagic disease is a naturally occurring virus in Missouri’s deer population," said MDC Wildlife Health Program Supervisor Brigid Niemeyer. "Outbreaks are most common between July and October and typically end after a heavy frost kills the midges that spread the virus."

MDC is asking residents to report suspected cases to help track the disease’s spread and assess its impact on deer numbers. Reports can be made by contacting a local MDC office, speaking with a conservation agent, or using the agency’s online Wildlife Health Event Reporting Application.

The agency notes that while HD can cause rapid, visible mortality, it does not have long-term effects on the overall health or sustainability of the state’s deer herd, which usually recovers within a few years after an outbreak.