The CDC closed some offices it leases in Atlanta after property managers discovered Legionella bacteria in water systems, reports CNN.
The bacteria, which can build up in stagnant plumbing systems, causes a respiratory condition called Legionnaires' disease. About 10 percent of cases are fatal, according to the CDC.
The bacteria was found in a cooling tower and several other water sources in the buildings, although no employees were sickened, the CDC said.
"Out of an abundance of caution, we have closed these buildings until successful remediation is complete," the agency told CNN.
Researchers and public health officials have warned about potential water quality concerns in unoccupied office buildings, hotels and gyms during the pandemic. The CDC shared guidelines to help prevent Legionella's spread as buildings reopen, but some experts are questioning whether they are effective, reports The New York Times.
"That the CDC can't prevent Legionella contamination in their buildings is a sign that we all need to be proactive about this issue," Caitlin Proctor, PhD, a postdoctoral fellow who studies the bacteria at West Lafayette, Ind.-based Purdue University, told the Times. "It's possible that these guidelines weren’t enough."