The Threat

WHAT IS ANTHRAX?

Anthrax is a rare disease that primarily affects animals, not humans. Anthrax is a bacterial infection caused by the organism Bacillus anthracis. It can be found in grass-eating wild and domestic animals, such as cows and sheep, most often in the agricultural regions of Asia, Africa, South America and parts of Europe (southern and eastern). The bacterium forms spores that can survive and lay dormant in the environment, for example, in the soil. These spores need a suitable environment to germinate and cause anthrax infection. This environment may be in the skin, lungs or the intestine. There are three main types of the disease, named to refer to the way the infection attacks the body - cutaneous (via the skin), gastro-intestinal (stomach), and pulmonary or inhalation (lungs). 

The deadliness of an anthrax terrorist attack depends obviously on the quantity of spores and the effectiveness of a delivery system. In 1970, the World Health Organisation estimated that, should 50kg of anthrax be released from an aircraft over an urban population of five million, there would be 250,000 cases of the disease. A 1993 report estimated that releasing a cloud of 100kg of spores upwind of Washington DC could cause between 130,000 and 3m deaths. In the 1990s, the Aum Shinrikyo terrorist group in Japan tried unsuccessfully to use anthrax as a biological weapon several times, leading them to change to sarin gas, with fatal results.   

Anthrax spores formulated as a white powder were mailed to individuals in the government and media in the U.S. in the autumn of 2001.  Postal sorting machines and the opening of letters dispersed the spores as aerosols. Several deaths resulted.  

The key events of the US Anthrax Attacks were: 

September 2001: Anthrax-laced letters are mailed to NBC, NY Post and the National Enquirer.  

October 2001: Robert Stevens, an employee of The Sun tabloid newspaper operated by American Media Inc (AMI) in Boca Raton, FL, checked into the hospital, extremely ill, but undiagnosed. Stevens becomes the first reported and confirmed inhalational anthrax case. Stevens dies of inhalation anthrax. Two mailroom employees at AMI test positive for exposure to anthrax spores. Spores are found on Robert Stevens' computer keyboard.  Letters containing anthrax were mailed to Senators Daschle and Leahy. At this point, letters are not known as the source of the anthrax in Florida.   New York City news organizations are the target of other anthrax-laced letters.  News anchor Tom Brokaw’s assistant tests positive for cutaneous anthrax. Brokaw's assistant recalls seeing a letter, weeks earlier, containing a brown, granular substance; most of which was discarded but the letter was kept.  Two New Jersey postal workers report possible anthrax symptoms; by October 20 both were diagnosed with inhalation anthrax.  Several Washington, D.C. postal workers are suspected of having anthrax. By October 25, two D.C. postal workers were dead and two more ill, as well as a U.S. State Department mail processor, all with inhalation anthrax.  Affected postal facilities and Senate office buildings are closed. Many government buildings also closed for testing during that period. U.S. mail undergoes irradiation to prevent other infections.  Antibiotics are distributed to postal workers and Senate staffers.  

After November 2001: Five people ultimately die of inhalation anthrax. Investigators continue to look for the people responsible for the anthrax attacks. The anthrax strain is identified as Ames and originates in the U.S. Postal facilities in Washington, D.C. are not reopened until 2003.   

Symptoms of Anthrax: 

Initially coughs and sneezes, much like a common cold. Within 36 hours chest pains, severe breathing problems and shock will develop. This type of anthrax usually results in death after about two days.

Effects of Anthrax: 

The spores are absorbed through the alveoli into the lymph system. They may not become active for up to two months. Once they germinate they release toxins which rapidly leads to haemorrhaging. Any delay administering antibiotics will reduce the chances of survival.  Anthrax spores tend to stick together and form a liquid sludge. To use anthrax as a weapon it must be converted into a powder which can be inhaled. The spores have to be very tiny - between 1 and 5 microns - and present in the air to be absorbed in the lungs.  

The biggest human exposure to inhalation anthrax occurred in 1979 at a military biology centre in Sverdlovsk, Russia. Anthrax spores were accidentally released resulting in 79 anthrax cases, 68 of which were fatal. 

During World War II Britain tested the use of anthrax as a weapon on the Scottish Island of Gruinard. The island was not decontaminated until 1987. A massive decontamination effort used 280 tons of formaldehyde and 2000 tons of seawater. 

Treatment of Anthrax:

Anthrax infection can be treated successfully when the disease is identified very early. Treatment is with a course of antibiotics. The antibiotic used to treat anthrax infection is ciproxin (In the US it is known as ciprofloxacin). High dose antibiotics are used, but victims showing advanced symptoms of the disease may not respond.  Once anthrax spores have lodged in the lung and caused an infection, nine out of 10 patients die. If antibiotics are given early, this will prevent only one of those nine deaths.

It isn't necessary to quarantine patients with confirmed anthrax because it's extremely unusual for anthrax to be transmitted from person to person. Anthrax can only develop if the bacteria gets into a cut or if enough anthrax spores are inhaled. 

Is there a vaccine?  

There is a vaccine against anthrax, but this is not recommended except for those at high risk, such as meat industry workers and laboratory scientists handling the disease.  

Be alert! 

There now exists a real threat that a Chemical, Biological or Radiological agent could be included into a terrorist IED to add to the destructive power and psychological effect of the device.  If you suspect you have received mail containing dangerous items, check the packaging thoroughly before opening.  Take special care with packages that have a strange odour, discolourations; or appear to contain powder or other unusual contents. If it happens at home, ring the police and follow their instructions. If you come across a suspect package at work, put it into your bin and place something on top of it, or put it in a plastic bag which can be sealed. Put a clear sign on the suspect package signifying it shouldn't be touched, then telephone the emergency number for your building, explaining who and where you are, how you can be reached by telephone and why you are suspicious. You may be asked where the item has come from and to whom it is addressed.  If you have already opened the mail or package and you're worried by the contents, remain calm, and ensure that no one enters or leaves the room. This is a precaution to limit those who might be exposed to any risk and to enable your employers to take quick action if appropriate. This advice applies equally in large, open-plan offices. Providing action is taken in the above fashion the risk from inadvertently opening a contaminated package is negligible, and any subsequent health effects are very likely to be treatable.   

WHAT ARE IMPROVISED EXPLOSIVE DEVICES (IEDs)? 

The military bomb, as we generally recognise it, is a ballistic shaped object filled with large quantities of explosive and dropped from aircraft from the air.  It is designed to explode on impact when it reaches its target.  But terrorists, criminals, extortionists and anti-social elements extensively use their own types of homemade bombs, called “Improvised Explosive Devices” or “IEDs”. 

EDs are often difficult to identify because they are constructed by terrorists entirely to their own design. As far as the technical aspects of constructing IEDs are concerned, devices have ranged from bombs made from normal everyday items, to highly sophisticated devices utilising digital components. Pipe bombs are one of the most common types of terrorist bomb.  Steel, iron, aluminium or copper pipes that are widely available are used in pipe bombs and low-velocity explosives are tightly capped inside.

The destructive powers of even small IEDs can be quite devastating if they incorporate military plastic explosives. Terrorists sometimes include shrapnel - which is metal items such as nails, nuts and bolts, steel ball-bearings, etc. – in their IEDs to cause greater injuries to victims.  In an explosion this shrapnel can travel up to a speed of 6000 km per hour, inflicting horrific injuries.   

IEDs are comprised of a few basic components, which will vary in basic appearance, but will generally always be present.   The component parts of a typical IED are as follows: 

1. The Explosive:   

Explosives are chemical compounds or mixtures which on application of an external stimulus such as heat, shock, friction or ignition undergo a dramatic chemical decomposition. At the most basic level, an explosive is just something that burns or decomposes very quickly, producing a lot of heat and gas in a short amount of time.   This chemical reaction results in a sudden release of large amounts of energy. When high explosives detonate, they release gases 12,000 to 15,000 times greater than their original volume and temperatures of 3000 to 4000 degrees centigrade.   The gas expands faster than the speed of sound and generates a powerful shock wave. The pressure can push pieces of solid material outward at great speed, causing them to hit people or structures with a devastating effect.  

The explosive charge in an IED can be military, commercial or homemade explosives – or a combination. Types of explosives that have been used by terrorists include RDX, C4 and SEMTEX - extremely powerful military explosives, PETN, which forms the core of explosive cord fuses, TNT, Dynamite, Black Powder - which is gunpowder, Smokeless Powder - which is the propellant in pistol and rifle bullets - and also homemade Improvised Explosive Mixtures based on common ammonium nitrate fertilisers, and other readily available household ingredients like wax, oil, paraffin and sugar. Homemade explosive mixtures are often extremely volatile and can be particularly susceptible to initiation by shock, friction or heat.   

Military plastic explosives are more stable, and they are extensively used by modern terrorists.  The basic principal of all plastic explosives, also called plastic bonded explosives, is to combine explosives with a plastic binder material. C4 is a relatively stable, solid explosive with a consistency similar to modelling clay – ideal for moulding into any article when constructing a camouflaged IED. When detonating, C-4 decomposes to release nitrogen and carbon oxides gasses which expand at about 8,000 meters per second, applying a huge amount of force to everything in the surrounding area.  Plastic explosives are very attractive to terrorists, as they can be moulded into an infinite number of diverse forms, including thin sheets about 5mm thick, which a terrorists have used to line suitcases, making detection extremely difficult. Plastic explosives have excellent adhesive properties - and can also be stretched into long, thin strands without breaking.  A distinguishing characteristic of many plastic explosives viewed under X-ray - except those in thin sheet form - can be their higher relative density compared with other common organic materials like paper, wood and plastics.   On a dual-energy X-ray image, military and commercial explosives will be coloured “orange” – the colour for organic substances.                                                      

2.  Power supply: 

Every IED needs a power supply, often using commercial batteries to trigger the initiator, known as the detonator.  In most day-to-day electronic devices that use batteries, several batteries are used together. Similarly, a terrorist may also need several batteries to sufficiently power an IED, and may tape a cluster of batteries together which can sometimes be of different types. The battery in an IED can, however, take many shapes and forms.

Batteries are generally full of carbon, with a metal casing. The carbon in batteries is organic, but because batteries are so dense and encased by metal, they will generally appear as blue or green on the X-ray screen, rather than the usual colour for organic material, which is orange.  Power sources are often the most visible components of an IED when viewed under x-ray.   

3. Initiator 

Most explosives need the application of a small explosion in an initiator, know as a detonator, to produce sufficient energy to trigger the secondary and/or main charge.  Detonators should be regarded as explosive devices in their own right.   There are basically two kinds of detonators, ‘Plain’ and ‘Electrical’.  Both types are made from a copper, glass or aluminium tube, closed at one end.   Detonators are generally extremely delicate structures, about 6mm diameter and 25 to 150mm in length. An electrical detonator uses a brief electric charge to set off small amounts of explosive material in the centre and tip of the detonator.  

Owing to their small size and relative lack of density, detonators can be difficult to detect with x-ray. However, there are some clues which can help you to spot detonators in items you screen: - Parallel wires that terminate suddenly are a useful indicator of a detonator. - Under X-ray, a small darker area is often visible at the centre of a detonator, because detonators have lead azide in them, making them partly x-ray opaque. This “detonator signature” is a useful way to identify if a small tube present in an item is a detonator.  

4. Switch: 

A switch can either be a complex electronic component, or as simple as two intersecting loops of wire. Switches are IED initiating mechanisms normally based on several types: Anti-handling switches are designed to activate when the IED is lifted, moved, opened or disturbed. Delay switches time the explosion by clockwork, digital, thermal, chemical or electro-chemical mechanisms. Switches can also detonate a device by remote control. A switch can be just one tiny component of a well-disguised IED, but switches can often be identified using x-ray if you ask yourself "Should this item contain any metallic components?” For example, a packet of biscuits should not have any metal displayed, nor should a box of chocolates.     

5. Wiring: 

Wiring is required to combine the components of an IED. Terrorists will often use various lengths of wire, without concerning themselves with the appearance of the item. The quality of the wiring may be inconsistent with the quality of the item. Or there could be excessive amounts of wiring for the size of the article.   Wires could even be protruding from the item. This can give you valuable clues that an electrical or electronic item has been tampered with.     

6. Timer/Delay Mechanism: 

The simplest delay mechanism is the slow-burning fuse. The use of mechanical clocks and wristwatches is also a common and effective method of delayed detonation in terrorist devices. The basic idea of clocks and wristwatches is to use the rotating hands to complete an electrical circuit and detonate the bomb. Digital and electronic timers are also often used by today’s sophisticated terrorists.   

WHAT ARE IMPROVISED INCENDIARY DEVICES (IIDs)? 

An IID is a device designed to destroy, incapacitate, harass, or distract by creating intense heat and fire, rather than by exploding. An IID’s design is limited only by the terrorist's imagination and ingenuity.  Incendiary devices are fairly simple to make and do not require access to explosives. The component parts of an IID will generally be an Incendiary Material; a means of ignition with possibly its own power source, like batteries; and a mechanism to ignite it. In December 2003, European Commission President Romano Prodi escaped unhurt after a postal IID was delivered to his Bologna home in Italy. The item, a wrapped book, burst into flames as he opened it.  "There was a big flame but without an explosion. It burned a piece of furniture and the carpet" Prodi said.   

When planning protective measures in office/retail premises, remember that incendiaries are generally small, that they ignite often when the target premises are empty, and that there is usually more than one device. The attacker will regard the attack as a success even if they do no more than trigger the sprinkler system, which itself can cause damage. You can make regular checks on fire extinguishers, sprinklers, smoke alarms and fire blankets. Since anyone finding a suspect device will probably be unable to tell whether it is incendiary or explosive, brief them to clear the surrounding area and call the police. If a device ignites, it may be sensible to make an immediate and brief attempt to extinguish it - provided normal fire arrangements and staff training are adequate. Remember, however, that there may be a number of devices and be prepared to evacuate the building according to pre-arranged plans.