Biological warfare. Conceptual computer artwork of bombs releasing spores (yellow), representing the use of biological pathogens in warfare. These can include bacteria and viruses, as well as fungi and protozoa. These could be natural, or they could be genetically modified strains designed to have the maximum impact on the target population. Some of the diseases that would be particularly deadly to a human population are ebola, anthrax, botulism, smallpox and bubonic plague. Biological pathogens could also be used by terrorists.