title: Characterizing the risk of infection from Mycobacterium tuberculosis in commercial passenger aircraft using quantitative microbial risk assessment.
abstract: Quantitative microbial risk assessment was used to predict the likelihood and spatial organization of Mycobacterium tuberculosis (Mtb) transmission in a commercial aircraft. Passenger exposure was predicted via a multizone Markov model in four scenarios: seated or moving infectious passengers and with or without filtration of recirculated cabin air. The traditional exponential (k = 1) and a new exponential (k = 0.0218) dose-response function were used to compute infection risk. Emission variability was included by Monte Carlo simulation. Infection risks were higher nearer and aft of the source; steady state airborne concentration levels were not attained. Expected incidence was low to moderate, with the central 95% ranging from 10(-6) to 10(-1) per 169 passengers in the four scenarios. Emission rates used were low compared to measurements from active TB patients in wards, thus a "superspreader" emitting 44 quanta/h could produce 6.2 cases or more under these scenarios. Use of respiratory protection by the infectious source and/or susceptible passengers reduced infection incidence up to one order of magnitude.
authors.affiliation: School of Public Health, University of California, Berkeley, CA, USA.
authors.forename: Rachael M
authors.initials: RM
authors.lastname: Jones
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Masago
authors.forename: Timothy
authors.initials: T
authors.lastname: Bartrand
authors.forename: Charles N
authors.initials: CN
authors.lastname: Haas
authors.forename: Mark
authors.initials: M
authors.lastname: Nicas
authors.forename: Joan B
authors.initials: JB
authors.lastname: Rose
mesh_terms: D000391:Air Microbiology / Q000592:standards*; D000401:Aircraft; D003198:Computer Simulation; D006801:Humans; D009010:Monte Carlo Method; D009169:Mycobacterium tuberculosis / Q000502:physiology*; D018570:Risk Assessment; D014376:Tuberculosis / Q000635:transmission*