Dallas city contractor 911 Wildlife says it is responding to about eight to 10 calls a day about raccoons sickened with distemper.
A North Texas wild-animal removal company is continuing to warn pet owners about "epidemic" levels of distemper in raccoons and other wild animals in Collin and Dallas counties.
Bonnie Bradshaw of 911 Wildlife, a contractor for the city of Dallas, told NBC 5 earlier this month that her organization was receiving an unusually high number of calls about sick raccoons.
The group has now seen more than 100 distemper cases. Bradshaw said 911 Wildlife is responding to about eight to 10 calls a day about raccoons sickened with distemper.
"It's a mystery to all of us," she said. "It started in mid-December, and it has just exploded since then."
Distemper is spread through the air and through mucus, primarily from direct contact or if an infected animal shares a food dish with an unvaccinated animal.
Bradshaw says pet owners should not leave out animal food dishes at night.
"That is creating a death trap for the raccoons, because if sick raccoons come up and eat in that area, it's going to spread to all the other raccoons eating in there," she said.
The majority of the distemper cases 911 Wildlife has seen have been in the area around White Rock Lake in Dallas and in Plano, McKinney and Allen in Collin County.
Flower Mound officials also said earlier this month that it had found the canine strain of distemper in wild foxes, as well as raccoons.
Animal owners need to vaccinate their pets for distemper, Bradshaw said.
Symptoms of distemper in dogs include sneezing, coughing and thick mucus coming from the eyes and nose, according to the American Society for the Prevention of Cruelty to Animals.
Distemper can be fatal in some animals. No current medication to rid an animal of distemper if it becomes infected is available, according to the ASPCA.