Emergencies preparedness, response

Summary of SARS and air travel

23 May 2003

This document addresses the main concerns of the public at large with regard to the risk of SARS (Severe Acute Respiratory Syndrome) transmission to passengers and/or crew embarking on an international voyage particularly from an area of recent local transmission. A more detailed account of the specific measures the World Health Organization (WHO) is recommending is available in the Weekly Epidemiological Record dated 4 April 2003. WHO has been working closely with international air transport organizations, including ICAO (International Civil Aviation Organization) and IATA (International Air Transport Association), to provide accurate information in a timely manner to all persons involved in international air travel in order to further reduce the risk of spreading the disease by this means.

Risk of SARS transmission in flight

The risk of transmission in aircraft is very low. To date, symptomatic probable SARS cases on four flights have been associated with possible transmission onboard. Two of these flights preceded WHO's 15 March 2003 emergency travel advisory, and since 23 March 2003 and the introduction of WHO-recommended screening measures by public health authorities no further cases of SARS in flight have been documented. A key factor in reducing the risk is for passengers and crew to be aware of the main symptoms of SARS which include high fever (>38 °C, 100.4 °F), cough, shortness of breath or breathing difficulties.

Measure for persons with symptoms compatible with SARS prior to departure

WHO has recommended that passengers or crew who develop symptoms compatible with SARS postpone their travel until fully recovered. WHO further recommends that public health authorities ensure that areas with recent local transmission introduce exit screening measures, which may include temperature checks for all passengers and crew. Preventing symptomatic passengers from travelling minimizes what risk there is. Finally, contacts of probable SARS cases should not undertake travel (national or international) for a 10-day period following exposure.

In-flight precautions and measures

Personal hygiene
All passengers and crews should observe good personal hygiene. Wash hands frequently, particularly before eating. If passengers or crew cough or sneeze while onboard, they should cover their mouth and nose, and wash their hands afterwards.

Face masks
Current evidence indicates that a person infected with SARS is not infectious to others unless s/he has symptoms. Therefore, WHO does not recommend the use of masks by asymptomatic passengers or crew. However, WHO recommends that passengers or crew presenting with symptoms compatible with SARS during a flight from an area with recent local transmission:

1) wear a protective face mask*;
2) be isolated, as far as possible, from other passengers; and
3) be given access to a toilet cordoned off for their exclusive use.

WHO also recommends that the designated crew member(s) caring for a person with symptoms compatible with SARS wear a protective face mask*, gloves and eye protection (e.g. tight-fitting goggles or face shield).

Measures on arrival of a flight with a suspected case of SARS

The Captain of an aircraft with a person presenting symptoms compatible with SARS onboard should radio the airport of destination so that appropriate arrangements may be made for reception and management by public health authorities. Passenger disembarkation may be delayed upon arrival while the medical officer at the airport of destination examines the patient. Following an assessment by public health authorities, passengers and crew may be required to provide their contact details for the next 14 days. All passengers and crew who are otherwise healthy should be allowed to continue their onward journey. If the ill passenger or crew member is confirmed as a probable case of SARS, public health authorities should notify contacts using the contact details provided.

Risk of infection from handling baggage or goods belonging to a SARS case

There is no evidence to date to suggest that a person can be infected with SARS from handling baggage or goods, as the major route of transmission is close face-to-face contact with a SARS probable case.

Aircraft ventilation

The configurations of the air circulation system for commercial aircraft are designed to the specifications of international aviation regulations, as well as guidelines of aircraft manufacturers:

Circulation: In flight, fresh air is introduced into the cabin continuously. The entire cabin air volume is exchanged every three minutes.

Airflow: The airflow movement is designed to minimize the potential for spreading of bacteria and viruses through the cabin.

Filter: Most major airlines install HEPA (High Efficiency Particulate Air) filters which are highly efficient in removing dust and airborne contaminants such as droplets, bacteria and large microbes.

This means that the spread of all microbes is minimized inside the cabin.

Disinfection of aircraft

Following a flight with a suspected SARS case, it is recommended that the aircraft be thoroughly cleaned following procedures established by local public health authorities which must involve the strict cleansing and disinfecting of the zone of risk in the cabin area (i.e. seats, headrests, tabletops, handsets, and other materials coming in contact with the suspected case) where the case was seated, as well as all shared facilities. The virus that causes SARS loses infectivity after exposure to commonly used disinfectants.

* N/R/P 95/99/100 or FFP 2/3 or an equivalent national manufacturing standard (NIOSH (N,R,P 95,99,100) or European CE EN149:2001(FFP 2,3) and EN143:2000 (P2) or comparable national/regional standards applicable to the country of manufacture.