Key Instruction Points
Vacate room and wait at least 30 minutes for infectious aerosols to settle before attempting a clean-up
Use sealed rotors or safety cups when centrifuging blood, pathogens or other potentially infectious materials.
Written emergency procedures should be clearly defined for potential accidents/incidents that can occur in the lab.
All personnel should be trained in emergency procedures when using hazardous materials.
A few years ago the newly discovered arenavirus, Sabia, was being studied by a visiting senior virologist, who was purifying it from one liter of tissue culture fluid. At the time of the incident, the virologist was working alone in the biosafety level-three laboratory (negative pressure with HEPA-filtered exhaust system). The researcher used a high-speed centrifuge with a large angle head centrifuge rotor with six new plastic bottles in the purification process. During the centrifugation cycle there was a nasty rattling sound that indicated a problem. As soon as the unit stopped, he opened the chamber and removed the bottles from the rotor and placed them in a biological safety cabinet. Only then did he realize that one of the plastic bottles had leaked about 100 ml of infectious tissue culture into the centrifuge rotor. (Subsequently a hairline crack was found.)
The researcher was probably exposed to aerosolized Sabia virus when he opened the chamber. He immediately disinfected the centrifuge rotor, the defective bottle and the centrifuge using 10% Clorox solution. He cleaned the spilled material from the centrifuge while wearing a gown, surgical mask, and gloves. After disinfecting the centrifuge and bottles, he continued to work in the laboratory for three to four more hours. He did not inform anyone or report the incident.
About ten days later he went to the doctor with a four-day history of fever, malaise, backache, stiff neck, and myalgias that he attributed to another cause. The diagnosis of Sabia Virus was made and confirmed. Although Sabia virus infection is potentially fatal, the researcher recovered after two weeks of treatment.
Persons who came into contact with the researcher or with his biological specimens in the hospital laboratories were notified and enrolled in a surveillance program. None of these persons developed the virus.
After this incident, the CDC classified Sabia Virus as a BL-4 pathogen, which requires use of a glove box or containment suit.
Personnel who work with BL-2 or higher materials must receive annual training in biosafety which should include how to recognize a potential exposure incident and procedures to follow in an emergency. Personnel working with higher level organisms need additional training.
Blood, other potentially infectious material and pathogens must only be centrifuged using a sealed rotor or safety cups. These must be opened in a biological safety cabinet.
If there is any incident which creates aerosols of an infectious material, the room should be evacuated and the material allowed to settle for at least 30 minutes before any clean-up activities are undertaken. The incident should be reported as an emergency to the Health and Safety Office. Possible personnel exposures should be treated as a medical emergency. The Health and Safety Office must evaluate the need for respiratory protection and other personal protective equipment before clean-up is performed.