Chemical weapons are most effective at committing atrocities against helpless civilians.
Thom Lang / Corbis
May 14, 2012 -
Recent controversial experiments and a research paper that detailed how to make an airborne version of the H5N1 avian influenza virus made some people nervous. The fear is that somebody, be it a terrorist group or unethical government, could create a superbug and use it as a biological weapon. But even it the recipe for avian flu hadn't been published, there are still plenty of other viruses to choose from. To be a good biological weapon, a pathogen should be transmitted from person to person, have an incubation or contagious period long enough that the infected patient can spread it and either incapacitate or kill.
Centers for Disease Control
Smallpox Top of the list is smallpox. Historically it's had a mortality rate of 30 to 35 percent, although it was much higher, sometimes 90 percent, in populations that were never exposed to it, such as Native Americans. Smallpox is an airborne virus, which means it can be caught easily from infected people who cough or sneeze, but can also be transmitted through touch. The disease creates a fever, malaise, head and body aches and sometimes vomiting. Two to four days later, a rash develops in the mouth and throat and sores break out on the skin. This is the most contagious period. Usually the rash spreads to the entire body in 24 hours. Ironically, most people feel better at this point. The rash becomes the classic pox after about three days, in which bumps are filled with fluid. The fever rises again at this time. Over the course of another week or two the pustules scab over, and when the last one is gone, the patient is no longer contagious. Smallpox has four varieties; three are often fatal. The last naturally occurring case of the disease was in 1975, in Bangladesh. However, the virus is still in cold storage at two labs, one in the United States and the other in Russia. For now, most people in their 20s and 30s might have no immunity at all. This is especially true in developing nations whose populations are generally younger. "A new outbreak in India or South Africa, for example, would be beyond terrible," said Tara Smith, an assistant professor of epidemiology at the University of Iowa.
Michael Abbey / Visuals Unlimited / Corbis
Resistant Bacteria Diseases that have been historically treated with antibiotics are good candidates for biological weapons because many strains have become resistant to the antibiotics. Methicillin-resistant staph, or MRSA, is one of the more well-known, and is spread by physical contact. MRSA usually stays in the skin, but in some people, it infects vital organs like the heart. Some varieties have caused necrotizing fasciitis, "flesh eating disease." A drug-resistant MRSA that was immune to all of the currently known antibiotics would cause many deaths. Tuberculosis is another that has evolved drug-resistant strains. The first totally drug-resistant form was identified in 2007 in Italy and by 2010, 8.8 million people had contracted it, with 1.4 million dying. Tuberculosis is the second biggest killer behind HIV/AIDS, according to the World Health Organization. It's spread person-to-person by coughing. The bacteria multiplies in the lungs, and patients die from respiratory failure or an excess of fluid in the lungs. Artificially breeding drug-resistant bacteria is no longer that complicated, Smith said. "Antibiotic resistance genes are easy to add to almost any bug, and some plasmids already carry resistance genes for multiple classes of drugs."
Centers for Disease Control
Bubonic Plague The Black Death or bubonic plague -- officially known as Yersina pestis -- killed a third of Europe's population in the 14th century, and it still exists in some parts of the world today. It has a long history as a bioweapon: accounts of the Mongol siege of the Crimean city of Caffa in 1347 say the invaders catapulted the corpses of infected people over the walls. And it isn't just a medieval phenomenon; the last major outbreak in the United States was in 1900 in San Francisco and involved 121 people of which 113 died; cases have appeared sporadically since. The plague is transmitted by fleas, which incubate the bacterium in their gullets. The multiplying Yersina block blood from getting to the fleas' stomachs, and the starving fleas start to feed more aggressively and try to clear the blockage by regurgitating the bacteria. That transmits the disease to hosts, including humans. Symptoms appear in two to six days. The infection causes the lymph nodes to swell (the "buboes"), but sometimes the bacteria invades the bloodstream directly and causes flu-like symptoms, without the swollen lymph nodes. In either case, mortality rates can be 40 to 60 percent if untreated. Infection of the lungs is the most serious form. The patient will cough up bloody sputum and droplets that help spread the disease person-to-person, and unless treated quickly mortality can approach 100 percent. The Black Death is treatable with antibiotics such as streptomycin now, but a resistant strain could be a serious public health problem.
Centers for Disease Control
Anthrax Anthrax is spread by spores, and those spores can survive in many environments, sometimes for years. There are three ways anthrax infects: breathing the spores, eating infected meat or having the spores get into cuts on the skin. Infection through inhalation is the most likely to kill, but anthrax is still quite dangerous. As the bacteria multiply in a person, they release toxins into the blood and tissues that cause swelling and cell death. Fatality rates are high, approaching 50 percent, even with treatment by antibiotics and 90 percent without that. It's not contagious, but a bomb can be made to spread the spores and infect many people at once. The spores can even be sent in the mail, as in the 2001 anthrax attacks. In those cases, envelopes containing anthrax spores were sent to several media outlets and the offices of two senators. Five people died and another 17 were infected. "Anthrax is great from the point of view that it is stable and not usually a suspect until it's too late to treat," Smith said. Anthrax produces symptoms that look like flu and unless there is a reason to think a person is infected, a doctor might not know to test for it. For a bioweapons manufacturer, however, the lack of person-to-person transmission means it needs to be released repeatedly. Anthrax is also vulnerable to antibiotics if caught early, though drug-resistant forms of it were experimented with in the United States until 1972 and the former USSR until the projects were abandoned in 1992. In 1942 the British government tested a strain of anthrax on an island in Scotland; decontamination didn't happen until 1990.
Sion Touhig / Corbis
Agricultural Pathogens As bad as pathogens are that kill people, those that attack animals or agriculture can have effects just as devastating. Rinderpest, which was declared wiped out in 2011, killed cattle at mortality rates of 100 percent, if the population had never been exposed previously. Hoof-and-mouth disease, caused by a virus in the genus Aphthovirus, remains active. It can infect cows, pigs, sheep and goats, and causes lesions on the feet and in the mouth. The mouth lesions sometimes keep animals from eating and the foot lesions can cause lameness. Some animals die from heart inflammation. It can be spread via contact with contaminated farming equipment, vehicles, clothing or feed. It also is carried by predators. During the 2001 outbreak in the United Kingdom, anyone traveling to the United States and Europe from there was asked to step onto a disinfectant pad to decontaminate their shoes, and livestock imports from Britain to the European Union were banned. The results were millions of animals being culled and billions of dollars in containment and lost business. To create mayhem, a terrorist could spray aerosols with the virus and devastate herds. "If someone would spray every herd he/she sees from a highway going from New York to San Francisco and then driving North-South (in the middle of the country), that would do it," said Peter Palese, chair of the department of Microbiology at the Mt. Sinai School of Medicine in New York. Other diseases could also become a problem, including H5N1 avian influenza, which infects the respiratory tracts and has a high mortality rate among chickens and poultry.
The Obama Administration, which last year warned the Syrian regime that using chemical weapons would cross a "red line" for unacceptable behavior, now seems to be preparing to inflict punishment upon Assad, probably in the form of an air strike.
But many people are wondering why Assad’s alleged use of chemical weapons is being seen by the United States as the last straw. After all, the Syrian civil war has been raging for more than two years, and 100,000 people already have died, many of them in atrocities that shock the conscience.
Last December, for example, a Syrian air force plane reportedly dropped eight cluster bombs on civilians waiting outside a bakery to buy bread in the small town of Halfaya, slaughtering 68 people.
"Anyone who has actually seen wounds from conventional artillery -- or badly treated body wounds from small arms -- realizes that chemical weapons do not cause more horrible wounds," Anthony Cordesman, an analyst for the Center for Strategic and International Studies, writes in a blog post. He argues that "the case for intervening cannot be based on chemical weapons."
But other experts say that chemical weapons, whose use was banned in warfare by a 1925 international treaty, do indeed cross a line, into a sort of brutality so extreme that the civilized world cannot afford to tolerate it. Because modern armies are equipped with protective gear, chemical weapons tend to be effective only for committing atrocities against helpless civilian populations. And in addition to inflicting excruciating pain upon victims who often die a lingering death, their use has an even more widespread, devastating psychological effect.
"Our minds are hard-wired to be afraid of poisons," explains Charles Blair, a senior fellow with the Federation of American Scientists who teaches graduate courses in biodefense at George Mason University and Johns Hopkins University. "Things that you can’t see or smell or taste are very frightening to people."
The psychological trauma inflicted by chemical warfare was documented in a 2006 study of survivors of the 1980-1988 Iran-Iraq war, one of the few modern conflicts in which militaries used such weapons. Researchers found that nearly 60 percent of subjects who'd been exposed to chemical weapons during the war suffered from post-traumatic stress disorder, about twice the rate of those who had been in the war but avoided chemicals. About 40 percent of the subjects who’d been exposed to chemicals suffered from severe depression, compared to only 12 percent of those without chemical exposure.
Chemicals have been used in warfare since ancient times, when Spartan soldiers burned wood dipped in a mixture of tar and sulfur to create noxious fumes on the battlefield. But it wasn't World War I that armies on both sides began deploying industrially-manufactured poison gases -- such as lung-searing phosgene and chlorine, and mustard gas, which causes blistering when it comes into contact with skin and mucous membranes -- as weapons.
An estimated 90,000 soldiers were killed by gas attacks during the war, and about a million soldiers suffered injuries that often plagued them for the rest of their lives, according to the Organization for the Prohibition of Chemical Weapons, an international monitoring group. In a secret report prepared at the war's end, U.S. Army Lt. Col. C.G. Douglas, a physiologist, concluded that "The particular value of the poison is found in its remarkable casualty-producing power as opposed to its killing power."
Chemical weapons are most effective at committing atrocities against helpless civilians.iStockPhoto
Despite their brutal effect, poison gases turned out not to be particularly effective in winning battles, because of their unpredictability.
"During the Great War, they didn't have reliable meteorology," explained John Pike, director of Globalsecurity.org, an Alexandria, Va.-based think tank on military and security issues. "They couldn't necessarily predict that the wind was going to blow the gas in the right or the wrong direction. Temperature and humidity also can change how chemical weapons work. In general, you'd like to be using weapons in a war that are not dependent upon guesses about weather."
The trauma of that war led nations to agree to forgo their use in warfare, but nevertheless, both the United States and the Soviet Union hedged their bets by building vast secret chemical arsenals, possibly as a deterrent against one another. In 1992, the Chemical Weapons Convention, another international treaty, banned nations who signed it from possessing such weapons at all.
The United States, which ratified the treaty in 1997, has since destroyed more than 80 percent of the nearly 30,000 tons of chemical warfare agents from its Cold War arsenal. U.S. forces, however, remain equipped with protective gear against chemical, biological and radioactive threats.
Chemical weapons became obsolete on the battlefield, but repressive regimes have turned to them for a different purpose -- attacks against civilians who lack the training and equipment to protect themselves. In 1988, for example, Iraqi dictator Saddam Hussein unleashed mustard gas and nerve agents sarin, tabun and VX against the Kurdish inhabitants of Halabja, a city in northern Iraq.
As many as 5,000 people died, and grisly photographs of the corpse-strewn city shocked the world.
"They're more of a taboo, because they’ve been effective against civilians," Pike explains. "And because they’ve been used against civilians horrifically."
Blair notes that different sorts of chemical weapons can be used for different purposes. Some poison gases quickly dissipate, allowing government troops to move quickly into an area and seize it. But more persistent gases can be used to keep adversaries out of an area completely.
"The high persistency agents -- remember the creature’s blood in the movie "Alien," how it would go through floors?" he said. "Some of these substances stick around like that."
Blair also points out that if Syrian use of chemical weapons is ignored, that may help to legitimize their use and encourage escalation to banned biological and radiological weapons as well. But he also worries that a U.S. air strike against the Syrian regime might cause a breakdown of the command-and-control structure and free local commanders to unleash more chemical attacks on their own.
"There might even be a system in place in Damascus, where subordinates have been told that if they lose contact with the high command, it's like a trip signal, for them to do as they see fit," he worries.
Here's a detailed guide to chemical weapons prepared by the Federation of American Scientists.