The U.S. Centers for Disease Control and Prevention will hire a laboratory safety supervisor after an Ebola virus sample was mishandled last week, the third reported safety lapse with potentially dangerous pathogens at the agency's labs in the past year.

The new position, posted nationally in November before the Ebola incident, is "under recruitment," Barbara Reynolds, a CDC spokeswoman, said in an email. The safety chief will be responsible for identifying problems, creating plans to solve them and holding CDC labs "accountable for follow-up," she said.

Scientists discovered Dec. 23 that a technician in one of the agency's labs was exposed to what may have been live Ebola virus. In March, the CDC inadvertently shipped a deadly strain of avian flu to a U.S. Department of Agriculture laboratory, and in June more than 80 CDC workers were potentially exposed to anthrax after a sample of the bacteria was mishandled, sparking congressional scrutiny of the agency and its director, Thomas Frieden, who pledged to improve safety measures.