Ticks may not be the only insect deer hunters should be worried about this season.
Penn State is researching Keds, a stable fly found on deer that, like ticks, can be a vector of disease.
Michael Skvarla, associate professor of entomology and biology at the College of Agricultural Sciences, wants to document the locations and distribution of Keds to determine if they pose a risk to human health. Research has found that the insects, an introduced species of stable flies originally found in Europe, Siberia and northern China, may be carriers of diseases normally associated with ticks.
Deer Keds are often confused with ticks by hunters and there is a resemblance, but the former are typically larger, ranging from 1/8 to 3/16 of an inch in length. Keds are also very mobile and can be found on deer bellies, while ticks adhere to the skin, don’t move much and are usually found around the head and neck.
“We are asking hunters to record the number of Keds that land on them, along with temperature and weather conditions, so we can attempt to determine the factors driving Ked incidence and where in the state hunters may be most affected by Ked- bites are threatened,” said Skvarla.
His research indicates that Keds can harbor Anaplasma, the bacteria that causes anaplasmosis, and Bartonella, the bacteria associated with bartonellosis.
Anaplasmosis is on the rise in Pennsylvania, according to Skvarla, and is carried by the same ticks that transmit Lyme disease.
“We’re not trying to scare hunters, but we want to let them know that these insects are around and they might be carrying pathogens,” he said.
The effects of deer keds on livestock are not certain, and the Pennsylvania Department of Agriculture is pleased that Penn State is investigating the potential risks to livestock, humans, and other mammals.
“It is not known whether deer-keds can transmit virus to livestock and humans, and the prevalence of deer-keds in livestock is uncertain,” said Shannon Powers, press secretary for the PDA.
Skvarla said Keds are a parasite that can be found on deer, elk, horses, cattle and even humans. A Ked’s bite on a human is barely noticeable at first, he said, but that changes over time.
“Within three days, the area develops into a hard, reddened wheal. The accompanying itching is intense and can last 14 to 20 days. This reaction is likely the result of the body’s response to the fly saliva,” Skvarla said.
David Stainbrook, deer and elk division chief for the Pennsylvania Game Commission, said he encounters more ticks than Keds on the deer he handles at processors in Dauphin, Perry and Mercer counties. As Stainbrook ages deer, he deals primarily with heads collected from processors, and Keds are likely to fall off, he said.
“The Keds can exit a carcass much faster because they don’t attach like a tick and are more mobile,” Stainbrook said. “But that also makes them more conspicuous because they move fast.”
Clinton Staniorski, a deer processor in Dorrance Township, Luzerne County, Pennsylvania, said it’s not uncommon to see Keds on the deer that hunters bring to his store.
“Mostly I see them on their stomachs and they look like big mosquitoes, but they don’t fly,” he said. “I see more ticks on the deer, but I definitely see Keds quite a bit, especially during archery season.”
Skvarla noted that he hopes to obtain Ked samples from hunters, particularly winged Keds, which fly in search of hosts from September to October – and sometimes as late as December.
Keds shed their wings once they land on a host and start feeding, he explained. If a winged ked is found carrying pathogens, it would indicate that they could be transmitted to humans.
To participate in Keds research, visit www.parasitehunters.com.
