Biohazard

The skittish behavior of microorganisms leads many experts to question their effectiveness as weapons. One of the problems has always been to find a reliable means of delivery, one that prevents biological agents from losing virulence when they are dispersed. It is the equivalent of what biologists call a "vector" for the transmittal of disease.

Over the centuries, armies have often used primitive methods to spread pestilence. The Romans dropped poison into wells to contaminate their enemies' water supplies. The English gave blankets smeared with smallpox to Indians in the eighteenth century during the French and Indian Wars. Confederate troops in the American Civil War left corpses of animals to rot in ponds along the path of Union forces. And during World War II, Japanese planes dropped porcelain bombs containing billions of plague-infected fleas over Manchuria.

The most effective way of contaminating humans is through the air we breathe, but this has always been difficult to achieve. Soviet scientists combined the knowledge gained from postwar biochemistry and genetic research with modern industrial techniques to develop what are called "aerosol" weapons — particles suspended in a mist, like the spray of an insecticide, or a fine dust, like talcum powder.

Temperature and weather conditions will determine the success of an aerosol's dissemination. Bacteria and viruses arc generally vulnerable to sunlight; ultraviolet light kills them quickly. Heavy rain or snow, wind currents, and humidity impede their effectiveness.

Such obstacles complicate the planning of a biological attack, but they are not insurmountable. A bioweaponeer will know to strike at dusk, during periods when a blanket of cool air covers a warmer layer over the ground — a weather condition called an inversion, which keeps particles from being blown away by wind currents. We packed our biological agents in small melon-sized metal balls, called bomblets, set to explode several miles upwind from the target city. Meticulous calculation would be required to hit several cities at the same time with maximum effectiveness, but a single attack launched from a plane or from a single sprayer perched on a rooftop requires minimal skill.

Primitive aerosols lose their virulence and dissipate quickly. In our labs, we experimented with special additives to keep our agents from decaying when transported over long distances and to keep them alive in adverse weather conditions. These manipulated agents, more stable and more lethal, were our biological weapons.

We would first test our aerosols in special static chambers, where air flow was controlled to monitor the particle distribution after a small explosion or discharge. The last stage in determining a weapon's efficiency was live animal tests, such as the ones we conducted in the Aral Sea.

We tested a variety of animals, including rabbits and guinea pigs, but monkeys, whose respiratory systems are so similar to ours, were the most effective surrogates for humans. An average person takes in ten liters of air every minute. A monkey inhales four. If four particles of an agent in a given volume of air killed at least 50 percent of the monkeys exposed to an aerosol, we could assume that ten particles would have an equally lethal effect on human beings.

Our standard measure of success for a biological weapon was referred to as Q₅₀, representing the amount needed to infect 50 percent of all exposed human beings in one square kilometer of territory. The Soviet Union devoted an enormous amount of time and money to developing concentrated aerosols that could reach the Q₅₀ level with minuscule numbers of bacterial cells or viral particles.

The most effective biological weapons go on killing long after they are used. Some viruses, such as Marburg, are so hazardous that casually inhaling as few as three microscopic viral particles several days after an attack would be enough to kill you. Biowarfare strategists often look beyond the immediate target to focus on the epidemic behavior of disease-causing agents.

Unlike nuclear weapons, which pulverize everything in their target area, biological weapons leave buildings, transportation systems, and other infrastructure intact. They should properly be called mass casualty weapons, not weapons of mass destruction.

Until General Yury Tikhonovich Kalinin took over Biopreparat in 1979, six years after it was created by a secret Kremlin decree, the agency didn't achieve much. Its first chief was an uninspiring but pleasant army general named Vsevolod Ogarkov, who was transferred from the Fifteenth Directorate, the branch of the defense ministry that had supervised the development of biological weapons since World War II.