From 2012:
"Simple mathematical analysis gives real reason for concern about the handling of these dangerous viruses. Consider the probability for escape from a single lab in a single year to be 0.003 (i.e., 0.3 percent), an estimate that is conservative in light of a variety of government risk assessments for biolabs and actual experience at laboratories studying dangerous pathogens. Calculating from this probability, it would take 536 years for there to be an 80 percent chance of at least one escape from a single lab. But with 42 labs carrying out live PPP research, this basic 0.3 percent probability translates to an 80 percent likelihood of escape from at least one of the 42 labs every 12.8 years, a time interval smaller than those that have separated influenza pandemics in the 20th century. This level of risk is clearly unacceptable."
The unacceptable risks of a man-made pandemic - Bulletin of the Atomic Scientists
"Simple mathematical analysis gives real reason for concern about the handling of these dangerous viruses. Consider the probability for escape from a single lab in a single year to be 0.003 (i.e., 0.3 percent), an estimate that is conservative in light of a variety of government risk assessments for biolabs and actual experience at laboratories studying dangerous pathogens. Calculating from this probability, it would take 536 years for there to be an 80 percent chance of at least one escape from a single lab. But with 42 labs carrying out live PPP research, this basic 0.3 percent probability translates to an 80 percent likelihood of escape from at least one of the 42 labs every 12.8 years, a time interval smaller than those that have separated influenza pandemics in the 20th century. This level of risk is clearly unacceptable."
The unacceptable risks of a man-made pandemic - Bulletin of the Atomic Scientists