Staphylococcal enterotoxins (SEs) are exotoxins produced primarily by Staphylococcus aureus, which is a ubiquitous microorganism with world-wide distribution (Bergdoll, 1983; Dinges et al., 2000). SEs are a major cause of food poisoning and they are also potent immune activators that lead to serious immune dysfunction (Alouf and Muller-Alouf, 2003; McCormick et al., 2001). Unlike most toxins, SEs are not directly cytotoxic and cell entry is not a requirement for them to cause an effect. The Centers for Disease Control and Prevention (CDC) place one SE, staphylococcal enterotoxin B (SEB), as a select agent based on its universal availability, ease of production and dissemination, and the potential to cause moderate but widespread illnesses. Additionally, because these agents are common to the environment and the diseases they cause are similar to other diseases, Category B agents require close environmental monitoring and enhanced disease surveillance (http://www.bt.cdc.gov/bioterrorism/).