A Primer of Biological Weapons

For combatants who lack the money to spend on high-tech killing instruments, biological weapons offer grisly appeal.

They are cheap, easy to make, and simple to conceal — and, since Sept. 11, on many minds. Even small amounts, if effectively deployed, could cause massive injuries and overwhelm emergency rooms.

The production of biological weapons can be carried out virtually anywhere — in simple laboratories, on a farm, even in a home.

Still, experts say it remains very difficult to transform a deadly virus or bacterium into a weapon that can be effectively dispersed. A bomb carrying a biological agent could likely destroy the germ as it explodes. Dispersing the agents with aerosols is challenging because biomaterials are often wet and can clog sprayers.

Biological weapons are defined as any infectious agent such as a bacteria or virus used intentionally to inflict harm upon others. This definition is often expanded to include biologically-derived toxins and poisons.

Types of Biological Weapons

Anthrax: The disease affects livestock, and has long been a focus of biological warfare research and development programs because it comes from relatively tough spores that can be sprayed over a battlefield or a city. Another name for anthrax is woolgatherer’s disease. Textile workers are commonly vaccinated against it.

Anthrax is most effective as a weapon when converted to a powder, which can be inhaled.

While in its first phase, anthrax is relatively easy to detect and treat. It initially causes flu-like symptoms, followed by severe chest congestion. Anthrax can then go dormant for several days. In the second phase, it is almost always fatal — vast numbers of the toxin-producing organisms accumulate in the body. Anthrax spores can live for years in carcasses buried in the ground.

Ricin: One of the most toxic naturally occurring substances known. It comes from the seeds of castor bean plants — which are also used to make castor oil. (The oil is derived from pressing the beans and keeping the ricin out.) Ricin was the poison used to kill the Bulgarian dissident Georgi Markow in London in 1978. The toxin was injected into him from the tip of an umbrella as Markow was waiting for a bus.

Botulism: Like anthrax, the bacteria for botulism can be found in soil, and the disease occasionally strikes people who eat badly canned food or fish in which the bacteria has grown. The bacteria produce an extremely toxic substance, botulinum, that causes blurred vision, dry mouth, difficulty in swallowing or speaking, weakness and other symptoms. Paralysis, respiratory failure and death follow. Botulism can be treated with an anti-toxin, but it doesn't do much good after the first burst of symptoms.

Smallpox: This disease was obliterated fully in 1980. The last known case was in Somalia. Smallpox is characterized in its classic form by the sudden onset of fever, headache, backache, vomiting, extreme physical exhaustion and even delirium. About two to three days after the onset of illness the true smallpox rash appears. Some Americans have been vaccinated against smallpox, but the vaccination lasts only 10 years. According to the CDC, vaccinations were stopped in the United States in 1971.

Clostridium Perfringens: A common source of food poisoning, the bacteria likes meat that has been kept at warm temperatures. Like anthrax, it forms spores that can live in soil.

Though its spores are less nasty in food, the organism causes gas gangrene when it finds its way into open battlefield wounds. Gas gangrene produces pain and swelling as the infected area bloats with gas. Later it causes shock, jaundice and death. Like anthrax, it can be treated with antibiotics such as penicillin — though in a laboratory, it’s not difficult to produce antibiotic-resistant strains by exposing the bacteria to non-lethal doses.

Camelpox: Little data exists on human exposure to this virus, which Iraq is said to have been developing. It is classified as among the riskiest (and illegal) foreign animal pathogens. Its possession, use and importation is outlawed in the United States.

Other Concerns

In addition to the diseases listed above, U.S. farmers and agriculturists worry that several foreign farm diseases — such as mad cow, African swine fever and soybean rust — could be used by terrorists to contaminate livestock and farm produce.

The Department of Health and Human Services says it has 15.4 million doses of smallpox vaccine and enough antibiotics against anthrax to protect two million people for two months. Some 40 million more doses of vaccine are on order will arrive by late next year instead of in 2005, as previously planned. More anthrax vaccine has also been ordered.

Still, some critics say public health services, including physicians and hospitals, are not prepared for a biological attack.

"There's a problem of coordination among local, state and federal agencies, which would be tripping all over each other in an actual incident," said Jonathan Tucker, Director of the Chemical & Biological Weapons Nonproliferation Program (CBWNP) of the Monterey Institute.

Those issues have gotten new attention — and taken on new importance — since Sept. 11.