(CBS) The Jaguars have apologized after their mascot made a sign during Sunday’s home loss to the Steelers that used the Ebola epidemic to make fun of Pittsburgh’s traditional Terrible Towels, ESPN.com reported Monday.

The hand-written sign read “Towels carry Ebola” and was created by Curtis Dvorek, who dons the mascot suit and portrays Jaxson de Ville, according to ESPN.com. The mascot also held a yellow towel while displaying the sign. Photos of the sign led to criticism on social media Sunday, and the Jaguars said they had no prior knowledge of the sign.

“Improvisation and humor have both been key elements to the character of Jaxson de Ville, especially when he performs at home games,” Jaguars president Mark Lamping said in a statement. “On Sunday, the person who has played Jaxson de Ville over the past 20 seasons made an extremely poor decision in that regard.”

Ebola is a viral disease that is highly infectious and is spread by contact with bodily fluids. It’s been the cause of 3.431 deaths in Guinea, Liberia and Sierra Leone, and it has a mortality rate close to 90 percent.