TB & Air Travel - Part 1

RANDOM THINGS FROM THE REPORT THAT I FOUND INTERESTING OR MIGHT NEED TO BE REMINDED OF LATER ON


Interferon-gamma release assay: An assay for cell mediated immunity to TB that measures interferon-gamma (IFN- ) released from peripheral blood T cells stimulated in vitro with TB antigens.
Acid-fast stain (e.g.carbol-fuchsin or auramine – Ziehl-Neelsen method)
Tuberculin. Purified protein derivative (PPD) – a mixture of antigens from a culture filtrate extract of M. tuberculosis that is used for skin testing; many of its antigens are non-species specific.
multidrug-resistant TB (MDR-TB): tuberculosis caused by
strains of M. tuberculosis that are resistant to at least isoniazid and
rifampicin;

The quality of the air on board commercial aircraft is high, and under normal conditions
cabin air is cleaner than the air in most buildings. On short flights, there is minimal risk of disease transmission.
Some countries (e.g. Australia, Canada and the United States of America) require TB screening to be done in the country of origin (a chest radiograph, tuberculin test) for adolescents and adults, and sputum smear examination if the chest radiograph is suggestive of TB disease. No person with a positive smear examination is permitted to immigrate.

Some countries (e.g. Switzerland, United Arab Emirates and the United Kingdom) screen immigrants and refugees when they enter the country.

A few countries require medical examination both in the country of origin and when entering (e.g. Bahrain, Kuwait, Qatar and Saudi Arabia). Thus, people with infectious TB would often be identified as having infectious TB only after they have travelled.

TB is an infectious disease, caused in most cases by M. tuberculosis and transmitted by exposure to tubercle bacilli in airborne droplet nuclei produced by a person with infectious TB during expiratory efforts, such as coughing, sneezing or singing.

To date, no case of active TB has been identified as a result of exposure on a commercial aircraft.
In the first report, evidence of transmission was limited to cabin crew with at least 12 hours' exposure to the infectious source. In the other, transmission of infection occurred to only a few passengers seated in the same section as and in close proximity to the passenger with infectious
TB, and only on one flight lasting more than eight hours.

Other potentially serious airborne or droplet-transmitted infections
that could merit public health interventions if encountered during air
travel are influenza (both seasonal influenza and any unusual strain such
as avian influenza affecting humans), measles, meningococcal disease
and SARS.

Tuberculosis and Air Travel - Guidlines for Prevention and Control - Second Edition
WHO