analysis circulated at the 2017 meeting for the Biological Weapons Convention, a conservative estimate shows that the probability is about 20 percent for a release of a mammalian-airborne-transmissible, highly pathogenic avian influenza virus into the community from at least one of 10 labs over a 10-year period of developing and researching this type of pathogen. This percentage was calculated from FSAP data for the years 2004 through 2010.

Analysis of the FOIA NIH data gives a much higher release probability—that is, a factor five to 10 times higher, based on a smaller number of incident reports.

While there is no obvious reason in the NIH data that would explain this high probability, exposures and latent (not-active) infections with M. tuberculosis was indicated in four incident reports. M. tuberculosis is not a select agent so incidents involving it would not necessarily be reported to the FSAP. Tuberculosis is highly contagious by the airborne route, so it might be easier to acquire a TB infection in the lab. Unfortunately, airborne TB infections might be a harbinger of what could occur in research on airborne-transmissible flu.

Facility-reported descriptions of the 11 relevant incidents are provided in the Supplementary Material (Appendix 2). Lab-acquired infections are often discovered some time after the incident occurred. Only for three were the causes confirmed to be human error. For the other eight, neither the infected lab workers nor facility officials knew how the infection occurred. While it is likely that human error was involved in many of these eight infections, their causes will never be known.