The U.S. Centers for Disease Control and Prevention has revealed that government labs improperly handled and sent potential pathogens such as anthrax to other labs.

Scientists claim that the labs in question did not deactivate deadly bacteria and did not follow proper procedures to transport the samples to other labs. The CDC suggests that labs mishandled highly-infectious H5N1 avian flu and anthrax samples.

The agency explains that a CDC team of scientists interviewed several laboratory scientists who were directly involved with the latest incident. The team also interviewed other scientists in the laboratory who possessed specific knowledge that was significant to the incident. Standard operating procedures and training records were also analyzed by the CDC scientists.

"The overriding factor contributing to this incident was the lack of an approved, written study plan reviewed by senior staff or scientific leadership to ensure that the research design was appropriate and met all laboratory safety requirements," stated [pdf] the CDC.

This is not the first incident which involved mishandling of deadly bacteria by federal government labs. Reports suggest that there have been five incidents in the last 10 years where labs have mismanaged bacteria samples.

Dr. Thomas Frieden, CDC's director, has also expressed his concern over the latest mishandling of bacteria samples. Frieden says that even though no individual was affected by the mishandling of the bacteria, it could have killed staff members and may have also affected people outside the labs. Frieden suggests that labs should have stricter control in place to avoid such incidents in the future.

It's not been long that government officials found vials that contained smallpox bacteria in a National Institutes of Health laboratory. The vials are said to be from 1954 and contained virus that could infect humans. All the samples of smallpox found in the vials will be destroyed.

Health authorities have officially announced Friday the temporary closure of two flu and anthrax CDC labs in Atlanta. Shipments of infectious bacteria from the agency's highest-security labs have also halted as a result of the latest incident.