DaSilva (1999) defined biological warfare as the intentional use of microorganisms, and toxins, generally of microbial, plant or animal origin, to produce diseases and deaths among humans, livestock and crops. Biological warfare and bioterrorism are very complex subjects, mainly due to the many agents that can be used as weapons and for the wide range of ways for dissemination into the environment and population. A biological event provides for the presence of at least two actors: one or more pathogens (bacteria, viruses or toxins) and a vehicle for their dissemination. In addition to the high spread capacity and lethality of potential biological agents, their invisibility and extremely difficult short-term detection makes it impossible for immediate diagnosis until the subsequent increase of infections. In fact, most biological weapons (except, for example, toxins and bacterial spores) have a unique quality that other non-conventional weapons (such as chemical and radiological) do not have; biological agents are able to multiply in the host organism and be transmitted in turn to new hosts, generating in this way with unpredictable effects on the population, both in terms of number of victims and geographical spread (Rotz et al., 2002; Zalini, 2010; Vogel, 2012; Tucker, 2013).
Among the reasons which make bioweapons attractive is their very low cost when compared to both conventional and unconventional weapons. For example, NATO (1996) reported that according to data processed in 1969 by U.S. experts, the costs for an attack on an area of 1 km2 to civilian populations with different weapons are: 1$/km2 for bioweapons, 600$/km2 for chemical, 800$/km2 for nuclear and 2,000$/km2 for conventional armaments. Furthermore, recent advances in life science and biotechnology have made it relatively straightforward to produce large quantities of biological agents with facilities and expertise available to everyone, even to terrorist and paramilitary groups (Zalini, 2010; Vogel, 2012; Tucker, 2013).ÊÊÊIn this paper, a summary of the main wars and terrorist activities carried out using bioweapons over the time is presented. In addition, the main biological warfare agents and related pathologies are considered, as according to the U.S. Centers for Disease Control and Prevention’s (CDC) priority classification. The emergence of potentially more destructive biological agents, due to the widespread introduction of biotechnology, is also analysed.
1 Pre-World Wars
The use of biological agents as war weapons is not a modern era novelty. Although it is not easy to identify a definite time when the use of bioweapons began, ancient evidence reported that in pre-Christian era, around 300 B.C., the Greeks used animal cadavers to contaminate water wells of enemies. This strategy was also used the by the Romans and Persians (SIPRI, 1971a). In a later period, during the battle of Tortona, Italy, in 1155, bodies of dead soldiers and animals were used to contaminate water wells by Emperor Barbarossa’s troops (Clarke, 1968). In the 14th century, during the siege of Kaffa by the Tartars (now Feodosiya, Ukraine, a city near the Black Sea, at that time under the control of the Genoese), among the Tartar army, an epidemic of plague was spread. The besiegers thought to catapult the cadavers of their dead comrades within the walls of the city of Kaffa, resulting in a turning point in the war; the Genoese fled from Kaffa, carrying with them their sick. On the return trip to Genoa, they ported at several ports in the Mediterranean Sea. While some sources believe a possible correlation between the epidemic of plague in Kaffa and the pandemic that decimated most of the population of Europe in the following decades (Black Death), most authors share the view of two events were independent (Wheelis, 2002).