Bioterrorism and the transport by air of dangerous pathogens

Dr. Ruwantissa Abeyratne

DEADLY VIRUSES: The recent recreation of the Spanish flu virus that killed 50 million people worldwide in 1918 proves that deadly viruses are being revisited and are undergoing genetic modification.

This brings to bear the inevitable question as to whether there is enough security to stop them from falling into the wrong hands. There is also the ominous prospect - that transportation of these dangerous pathogens by air would leave aviation vulnerable.

Pathogens are microorganisms (including bacteria, viruses, rickettsia, parasites, fungi) or recombinant microorganisms (hybrid or mutant) that are known or are reasonably expected to cause infectious disease in humans or animals.

Although, past instances of escaping dangerous pathogens are small in number, nonetheless their occurrence

 and the threat posed to the wellbeing of humanity cannot be underestimated.

In 2002 when Anthrax spores escaped from two military laboratories in the United States, the authorities agreed that the leakage was due to a security lapse.

An year earlier, a covert event occurred in October 2001 when anthrax spores were sent through the mail exposing persons in the eastern USA to contaminated mail resulting in deaths, illnesses and identified exposures to Anthrax. Overt, announced events, in which persons are warned that an exposure has occurred, have taken place in the United States, although most of these were determined to have been hoaxes, that is, there were no true exposures to infectious agents.

In 2003 a string of such leakages occurred in Asia, this time of the SARS virus. The leakages occurred in China, Taiwan and Singapore.

It is now known that the laboratory is not the only place where security lapses could occur. Modern exigencies require samples of deadly pathogens to be transported regularly over vast distances to reach researchers across the world.

This calls for a delicate balance between recognising the compelling need for scientists to exchange and collectively use different strains in order to identify naturally occurring diseases and mutations on the one hand and ensuring that the safe transport of these infectious substances are carried out according to United Nations Model Regulations on the other.

Infectious substances are defined as substances known to contain, or reasonably expected to contain, pathogens.

The United Nations has developed recommendations on model regulations for the transport of dangerous goods which recognise that various chemical combinations and mixtures have different requirements in packing for the purpose of transport.

The United Nations Model regulations contain packing instructions for primary, secondary and outer packaging of hazardous goods, known or reasonably expected to contain pathogens that are to be classified as infectious substances.

When these specimens are transported/shipped for any purpose, including initial or confirmatory testing for the presence of pathogens, they are to be packaged and shipped as infectious substances.

These model regulations are the base upon which specific provisions for the carriage by air are formulated in the packing of samples of infectious pathogens for transportation by air. The shipment of infectious agents or diagnostic specimens by air must comply with local, national and international regulations.

Air transport regulations

International air transport regulations are contained in various documentation of the International Civil Aviation Organisation (ICAO) and Dangerous Goods Regulations - an annual publication of the International Air Transport Association (IATA) published in January, and usually revised on an yearly basis.

Dangerous Goods Regulations are implicitly accompanied by the requirement that anyone requesting samples should provide the necessary evidence that they are registered with their government for the receipt of such substances and that they have the appropriate facilities, staff and security measures in place to carry out work on the samples received.

There are four diseases recognised as most likely to be associated with bioterrorism potential: anthrax; botulism; plague; and smallpox.

Although these agents are considered to be the most likely to be used in bioterrorism they are not usually prioritised in any order of importance. There are other agents which offer potential to bioterrorism such as those causing tularaemia, brucellosis, Q fever, viral haemorrhagic fevers, viral encephalitis, and a disease associated with staphylococcal enterotoxin B.

There are others which cause security experts concern as emergent threats to security through bio terrorism. These are Severe Acute Respiratory Syndrome (SARS), monkeypox and pandemic influenza.

These are naturally occurring diseases, which are of concern because they are new and/or epidemic. An outbreak is usually identified consequent to a rapidly increasing disease incidence (e.g., within hours or days) in a normally healthy population, such as unexplained death with fever in a non-trauma patient, or a botulism-like syndrome, meningitis or encephalitis in more than one patient.

Rapid response to a dangerous pathogen event requires prompt identification of its onset. Because of the rapid progression to illness and potential for dissemination of some of these agents, it may not be practical to await diagnostic laboratory confirmation.

Instead, it is necessary to initiate a response based on the recognition of high-risk syndromes, i.e., typical combination of clinical features of the illness at presentation that might alert healthcare practitioners to the possibility of an outbreak.

Examples of syndromes potentially resulting from infections with dangerous pathogens include: encephalitis/meningitis, haemorrhagic mediastinitis, severe pneumonia, papulopustular rash, haemorrhagic fever, descending paralysis and nausea/vomiting/diarrhoea.

Outbreaks of dangerous pathogens may occur naturally or as covert or overt events. An outbreak is suspected only upon recognition of unusual disease clusters or symptoms. For example, SARS was recognised as a naturally occurring event initially from Southeast Asia in February 2003.

Bioterrorism

A bioterrorism attack is the deliberate release of viruses, bacteria, or other germs (agents) used to cause illness or death in people, animals, or plants. These agents are typically found in nature, but it is possible that they could be changed to increase their ability to cause disease, make them resistant to current medicines, or to increase their ability to be spread into the environment.

Biological agents can be spread through the air, through water, or in food. Terrorists may use biological agents because they can be extremely difficult to detect and do not cause illness for several hours to several days. While some bioterrorism agents, such as the smallpox virus, can be spread from person to person some agents such as anthrax are incapable of doing so.

noteworthy instances

There have been several noteworthy instances of bioterrorism in the past as early as 1915, which send an ominous message that it is even at this point in time a distinct possibility in the aviation context.

In 1984 followers of the Bhagwan Shree Rajneesh attempted to control a local election by incapacitating the local population by infecting salad bars in eleven restaurants, doorknobs, produce in grocery stores and other public domains with Salmonellas typhimurium in the city of The Dalles, Oregon.

The attack caused about 751 people to fall ill (there were no fatalities). This incident was the first known bioterrorist attack in the United States in the 20th century.

In September and October of 2001, several cases of anthrax broke out in the United States which were reportedly caused deliberately. This was a well-publicised act of bioterrorism.

It motivated efforts to define bio surveillance, bio defence and bio security . Bio surveillance is the science of real-time disease outbreak detection. Its principles apply to both natural and man-made epidemics (bioterrorism).

It is worthy of note that in addition to activity in this field in the United States, there is also work being done in Europe, where disease surveillance is beginning to be organised on a continent-wide scale needed to track a biological emergencies.

The system not only monitors infected persons, but also attempts to discern the origin of the outbreak.

Until recently in the United States of America, most biological defense strategies have been geared to protecting soldiers on the battlefield rather than looking after ordinary people in cities.

In 1999, the University of Pittsburgh’s Center for Biomedical Informatics deployed the first automated bioterrorism detection system, called RODS (Real-Time Outbreak Disease Surveillance).

RODS is designed to draw collect data from many data sources and use them to perform signal detection, that is, to detect a possible bioterrorism event at the earliest possible moment. RODS, and other similar systems, collect data from sources including clinical data, laboratory data, and data from over-the-counter drug sales.

In 2000, Michael Wagner, the co director of the RODS laboratory, and Ron Aryel, a subcontractor, conceived of the idea of obtaining live data feeds from “non-traditional” (non-health-care) data sources. The RODS laboratory’s first efforts eventually led to the establishment of the National Retail Data Monitor, a system which collects data from 20,000 retail locations nation-wide.

On February 5, 2002, President Bush visited the RODS laboratory and used it as a model for a $300 million spending proposal to equip all 50 states with bio surveillance systems. In a speech delivered at the nearby Masonic temple, President Bush compared the RODS system to a modern “DEW” line (referring to the Cold War ballistic missile early warning system).

The principles and practices of bio surveillance, a new interdisciplinary science, were defined and described in a handbook published in 2006. Data which potentially could assist in early detection of a bioterrorism event include many categories of information.

Health-related data such as those collected from hospital computer systems, clinical laboratories, electronic health record systems, medical examiner record-keeping systems, 911 call center computers, and veterinary medical record systems could be of help in the fight against bioterrorism.

Researchers are also considering the utility of data generated by ranching and feedlot operations, food processors, drinking water systems, school attendance recording, and physiologic monitors, among others.

Intuitively, one would expect systems which collect more than one type of data to be more useful than systems which collect only one type of information (such as single-purpose laboratory or 911 call-center based systems), and be less prone to false alarms. This indeed appears to be the case.

The inherently uncontrollable nature of a dangerous pathogen makes bioterrorism unattractive as a warfare strategy. However, the potential power of genetic engineering cannot be marginalized or underestimated and the compelling need for continuing vigilance cannot be ignored.

Incontrovertible truths

There are a few incontrovertible truths that drive the issue of the illegal carriage of infectious pathogens by air. The first is that, as recognized by WHO and demonstrated by IATA (which publishes its highly effective and widely accepted Regulations in consultation with ICAO), the lead role in legislative and regulatory control of the issue lies well within ICAO.

The second is that, one has to go back to the basics of the rule book and start with the Preamble to the Convention on International Civil Aviation of 1944, which is the cornerstone of aviation regulation.

The Preamble unequivocally links the future development of aviation to “general security” which essentially means that aviation should not only be concerned with persons and property directly involved with air transport but also with the rest of the world that might be adversely affected by the release of infectious pathogens through aviation.

The third home truth is that it is a pre-eminent responsibility of States to ensure security at laboratories in their territories as the illegal carriage of infectious substances by air is linked to the initial leakage from a laboratory.

Therefore, it is extremely important for States to strictly enforce their dangerous goods legislation. It is also important to treat this subject holistically in terms of the world at large and not restrictively by singling out only those involved in the flight concerned.

Finally, States have to adopt a security culture that admits of an overall approach to the threat as a potential harm to the health of humanity.

This should inevitably include strict adherence by States to the ICAO provisions inclusion of new Standards as necessary, together with an abiding understanding that the illegal carriage of infectious pathogens by air portends a threat both to safety and security of aviation.

The writer is the Coordinator, Air Transport Programmes, International Civil Aviation Organisation, Montreal, Canada.