The Wildlife Health Center, however, notes "the virus generally cannot be cultured at temperatures above [86 degrees], so it probably is not infectious to domestic mammals and humans."
Adkins Giese also said in the letter that the race strains native turtle populations and that Maryland law prohibits wild collection of any spotted turtles, wood turtles or diamondback terrapins, or possession of more than one of many other turtles found in the state, such as eastern box turtles or painted turtles.
"Turtle races can also spread disease to people who handle turtles, including young children who are especially vulnerable," according to the letter. "Of particular concern is the risk of Salmonella infection, which can cause severe illness and even death."
Bel Air's Independence Day Committee has already warned on its website that no turtles entered in the race can have a carapace less than 4 inches long and limits participants to one member of each turtle species per adult, citing DNR restrictions.
Local conservationist Bob Chance said Monday he saw both sides of the issue, noting the derby has been going on for half a century.
"This is a gigantic controversial issue," he said. "Every year it gets a little dicier."
Although he did not know about the ranavirus, "I know a lot of wild-caught turtles that get used in this race get displaced, they don't get returned to the place where they were found, and that really confuses the animal. They are totally disoriented. Sometimes it's a very hot day, sometimes the turtles are not properly fed before the event."
"On the other hand, this Independence Day tradition has been an educational tool," Chance continued.
Canceling the race "could possibly affect a few people's science careers," he explained.
Because of that, Chance has reservations about calling off the derby completely.
"I have a lot of people tugging on me on this issue in both directions," he said. "Shucks, you have 150 entries [for the derby]."
Chance pointed out hamster races have been discontinued, but Bel Air's frog jumping contest goes on despite some drawbacks.
"A lot of frogs get injured in the jump, but it's carnival, old-time Americana," he said.