Background: Proximity to an infectious TB case is a potential risk in any close contact setting. However, the rapid growth in airline transportation is in stark contrast to the lack of evidence about the prevalence of TB among airline passengers and crew. The rate of ventilation in the aircraft cabin is far superior to other forms of transportation and reduces the risk of airborne transmission.
Methods: This study calculated TB disease rates among passengers and cabin crew during the 5-year study period. The principal study outcome was the number of notifications of confirmed TB disease cases and potential under-reporting was estimated. The airline rates were compared with the WHO definition of low incidence--"a TB notification rate below 10 per 100,000 population and declining".
Findings: The TB case notification rate was 0.05 per 100,000 long-haul passengers. The risk increased seven-fold on flights from TB-endemic areas in Africa or India. The aircraft cabin remains classified as a low TB incidence environment on all routes within a wide margin of error. Low occupational prevalence was observed in the cabin crew workforce.
Interpretation: Airline passengers are considered to be a select group with low TB rates. This study provides important evidence that confirms the aircraft as a low-risk setting for transmission of TB and emphasizes the presence of environmental-control measures that reduce the risk as far as possible.