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or illness to a host. These biopathogens include, but are not limited to, bacteria, bacterial spores, viruses, molds, fungi, and their toxins. Pathogenic bacteria can cause infectious diseases; the most common bacterial disease is tuberculosis, which is caused by the bacterium Mycobacterium tuberculo› sis. Mycobacterium is a genus of Actinobacteria, which includes many pathogens known to cause serious diseases in mammals, including tuberculosis and leprosy. Pathogenic bacteria also contribute to other globally important diseases, such as pneumonia, which can be caused by bacteria such as Streptococcus and Pseudomonas, and foodborne illnesses, which can be caused by bacteria such as Shigella, Campylo› bacter, and Salmonella. Pathogenic bacteria also cause infec› tions such as tetanus, typhoid fever, diphtheria, syphilis and leprosy. Pathogenic viruses are mainly those of the families of: Adenoviridae, Picornaviridae, Herpesviridae, Hepad› naviridae, Flaviviridae, Retroviridae, Orthomyxoviridae, Paramyxoviridae, Papovaviridae, Rhabdoviridae, Togaviri› dae. Some notable pathogenic viruses cause smallpox, influ› enza, mumps, measles, chickenpox, and rubella. 

[0020] The threat from biological toxants can be even more serious than the chemical warfare threat. This is in part because of the high toxicity of BW agents, their ease of acquisition and production, and their difficulty in detection but also, as in the case of pandemics, their ease of transmis› sion and spread. There are hundreds of biological warfare toxants known, with new viruses appearing constantly. For decontamination purposes, biological toxants can be usefully distinguished as spore forming bacteria which can exist in a vegetative state ( e.g., Bacillus anthracis which causes anthrax), bacteria which are vegetative but non-sporulating ( e.g., Yersinia pestis the cause of plague, Vibrio cholerae the cause of cholera), non-lipid and small viruses (e.g., polio viruses), fungi (e.g., Trichophyton spp.), lipid and medium size viruses (e.g., retroviruses like HIV, Hepatitis B viruses), and bacterial toxins (e.g., botulism, ricin). 

[0021] With the exception of prions, bacterial spores are recognized to be the most difficult microorganism to kill. Prions are infectious agents composed of protein which propagate by transmitting in a mis-folded protein state, and are not generally considered biological warfare agents. Bac› terial spores are highly resistant structures formed by certain gram-positive bacteria usually in response to stresses in their environment. The most important spore-formers are mem› bers of the genera Bacillus (e.g., Bacillus anthracis) and Clostridium (e.g., Clostridium difficile). Spores are consider› ably more complex than vegetative cells. The outer surface of a spore consists of the spore coat that is typically made up of a dense layer of insoluble proteins usually containing a large number of disulfide bonds. The cortex consists of peptidogly› can, a polymer primarily made up of highly crosslinked N-acetylglucosamine and N-acetylmuramic acid. The spore core contains normal (vegetative) cell structures such as ribo› somes and a nucleoid. 

[0022] Antiseptics and disinfectants are used extensively in hospitals and other health care settings for a variety of topical and hard-surface applications to deal with biological toxants. In particular, they are an essential part of infection control practices and aid in the prevention of nosocomial infections. There are a variety of sterilants and disinfectants that can be used to address decontamination of one or more biological pathogens, as shown in Table 1. 

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[0023] "Biocide" is a general term describing a chemical agent, usually broad spectrum, that inactivates microorgan› isms. Because biocides range in antimicrobial activity, other terms are more specific, including "-static," referring to agents which inhibit growth (e.g., bacteriostatic, fungistatic, and sporistatic) and" -cidal," referring to agents which kill the target organism (e.g., sporicidal, virucidal, and bactericidal). Disinfectants are generally products or biocides that are used on inanimate objects or surfaces. Disinfectants can be sporo› static but are not necessarily sporicidal. Sterilization refers to a physical or chemical process that completely destroys or removes all microbial life, including spores. 

[0024] Different types of microorganisms vary in their response to decontaminants and disinfectants, as shown below, in descending order. 

[0025] Prions* 

[0026] (CJD, BSE) 

[0027] Coccidia 

[0028] ( Cryptosporidium) 

[0029] Spores 

[0030] (Bacillus, C. Difficile) 

[0031] Mycobacteria 

[0032] (M. tuberculosis, M. avium) 

[0033] Cysts 

[0034] (Giardia) 

[0035] Small non-enveloped viruses 

[0036] (Polio Virus) 

[0037] Trophozoites 

[0038] (Acanthamoeba) 

[0039] Gram-negative bacteria (non-sporulating) 

