AMES, Iowa (AP) – Six Iowa State University students living in a rented home in Ames have been vaccinated for rabies after officials learned they have collectively killed 23 bats in their home. The Des Moines Register reports the students were vaccinated Tuesday night. Ames Animal Control supervisor Ron Edwards told the students and their girlfriends to get vaccinated once he learned how many bats they had been exposed to. One bat tested negative for rabies.

Twenty-one-year-old Quinn Nordland said a roommate found the first bat in the basement Aug. 30, and another one the next morning. The bats kept continued to appear and the students would walk the hallways at night with tennis rackets to combat the animals.

The students said the infestation has persisted despite reporting it to their landlord. Mike Fresco of First Property Management said a company has been hired to find a solution to the problem.