In-flight disease transmission

Concern has been increasing about those possible spread of communicable diseases during air travel. Infections of particular concern include tuberculosis, Neisseria meningitidis, measles, influenza and SARS.

Only one investigation has documented transmission of Mycobacterium tuberculosis (TB) from a symptomatic passenger to six other passengers who were seated in the same section of a commercial aircraft during a long flight (>8 hours). These six passengers were identified by conversion to a positive tuberculin test; none had evidence of active tuberculosis. The HEPA-filters used in newer commercial aircraft (described above) are able to filter out TB bacteria from the recycled air and are used in hospital respiratory isolation rooms to prevent the spread of TB within the hospital setting. Furthermore, the number of air exchanges per hour in airplanes exceeds the number recommended for hospital isolation rooms. The risk of TB transmission on commercial aircraft, therefore, remains low. People known to have infectious TB should travel by private transportation, rather than a commercial carrier, if travel is required.

Neisseria meningitidis
Meningococcal disease has been documented in travelers, particularly those traveling for the Hajj; however, transmission due to exposure while aboard an aircraft has not been documented. Guidelines for the management of airline passengers who have been exposed to meningococcal disease are available; please contact Protea Tours for further information’s.

Measles is a high contagious viral disease. Most cases diagnosed are imported from countries where measles is still endemic. Furthermore, a person infected with measles in contagious from the first onset of vague symptoms (up to 4 days before rash) to approximately 4 days after the development of rash; therefore, the potential for disease transmission during air travel is a concern. Despite the risk, very few cases of measles have been documented as a direct result of in-flight exposure. Travelers should ensure they are immunized if they have not had the disease.

Influenza is highly contagious, particularly among people in enclosed spaces. Transmission of infection has been documented aboard an aircraft, with most risk being associated with proximity to source. Since December 2003, a new strain of avian influenza has been shown to cause infection to humans, with limited human-to-human spread. Because influenza viruses are very adept at changing, there is concern that this strain could eventually become a threat and this affect air travel.

SARS was first identified in South China in November 2002 and recognized as a global threat by March 2003. it is caused by a new coronavirus, the SARS-associated coronavirus. Despite the clear role of international travel in the spread of SARS during the 2003 outbreak, only one case of in-flight transmission has been confirmed. From investigations of disease outbreaks associated with air travel, two main risk factors for the spread of communicable diseases have been identified: flight duration (>8 hours) and seating proximity to the source. There is also increased risk of spread when the aircraft ventilation system is off. in general, the environmental systems are on when the engines are on or when an auxiliary unit is used, such as when the aircraft is on the ground at the gate. to reduce the spread of disease, standard respiratory and hand hygiene practices should always be encouraged. People with febrile illnesses or other possible communicable diseases should postpone air travel. Furthermore, airline regulations require that passengers be removed from an aircraft within 30minutes of shutting off the ventilation system.

To reduce the international spread of mosquitoes and other vectors, a number of countries require disinsection of all in-bound flights. WHO and the International Civil Aviation Organization (ICAO) specify two approaches for aircraft disinsection: either spray the aircraft cabin with aerosolized insecticide (usually 2% phenothrin) while passengers are on board, or treat the aircraft's interior surfaces with a residual insecticide while the aircraft is empty. Some countries use a third method, in which aircraft are sprayed with an aerosolized insecticide while passengers are not on board. Although disinsection, when done appropriately, was declared safe by the WHO in 1995, there is still much debate about the safety of the agents and methods used for disinsection. Although passengers and crew members have reported reactions to both the aerosols and residual insecticides, including rashes, respiratory irritation, burning eyes, and tingling and numbness of the lips and fingertips, there are no data to support a cause-and-effect relationship. Guidelines for disinsection are being updated for the revised international Health Regulations. While only a few countries require disinsection for all in-bound flights, many countries reserve the right to increase the use of disinsection in the setting of increased threat of vector or disease spread.

ALOR DIVE wish you a pleasant journey

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