A laboratory building on the federal Centers for Disease Control and Prevention’s DeKalb County campus was closed Wednesday because of an overnight fire in a rubella lab, a CDC spokesman said.

The fire broke out around midnight in Building 18, CDC spokesman Thomas Skinner said.

“No one was injured and there was no release or loss of containment of any germs,” Skinner told Channel 2 Action News in an email.

While the cause of the fire is under investigation, “early indications point to a piece of laboratory equipment that malfunctioned,” he said.

Skinner said the building, which houses 470 employees working on rubella, measles, mumps, HIV, meningitis, hepatitis, norovirus and other pathogens, will remain closed as officials assess the extent of damage, which he said was primarily caused by the building’s sprinkler system.