Estimates of risk associated with a tuberculosis patient and air travel

SUMMARY OF THE RESULTS OF THE ANALYSES (See sections below for model descriptions and Appendix for parameters used) Risk of infection on average ranged from 1/1000 to 4/10,000, with detectable average ranges of bacilli in the saliva, however with non-detectable bacilli, the risk was seen as less that 2/100 million to approximately 6/billion. .The estimated probabilities of producing infections or deaths (assuming NO treatment) during an 8 hour flight are summarized in Table 1 and Figure 1. Because we did not have the concentration of M. tb in saliva of the patient at the time of the trip, the concentrations were assumed based on data from symptomatic patients (Yeager et al., 1967). Table 1. Estimated probabilities of 1 or more infection, and 1 or more death, among passengers seated in 5 rows around the source patient. M. tb concentration Model A Model B in saliva [CFU/ml] Infection Death a Infection Death a Non-detectable (Assumed < 1 CFU/ml) < 5.8 × 10 -9 < 1.3 × 10 -10