Biological threats categories

The virus that causes smallpox. Variola major, is a Category A biological threat agent (CDC 2007). It is a double-stranded DNA orthopoxvirus. It is a widely held opinion among infectious disease professionals that, historically, smallpox has been responsible for more deaths than all other infectious diseases combined. After aggressive efforts by the World Health Organization to immunize the world s population, and because the virus is unable to survive for more than a week outside of its only host, humans. Variola was declared eradicated in 1980 (Murray et al. 2005). The smallpox vaccine can prevent or lessen the severity of the disease if administered within 96 h of exposure. The duration of effectiveness of the vaccine used to eradicate smallpox is not known, and there are reported mild to life-threatening risks are associated with the vaccine. Once a victim is symptomatic, medications and intravenous fluid can be administered to make the patient more comfortable, but there are no antivirals available for unvaccinated infected individuals (Henderson et al. 1999). 

Ebola, Lassa, Machupo, and Marburg are some of the 18 different viruses that cause viral hemorrhagic fever (VHP) in humans and other primates that are classified as Category A biological threat agents (CDC 2007). Ebola is a zoonotic disease of primates and occasionally spreads to human populations that are exposed to these animals (Murray et al. 2005). 

Many types of threat agents might be used in an attack on the air transportation system. Each has its own set of physical, chemical, and biological characteristics, which would determine how lethal and widely dispersed the effects would be. Four different categories of threat agents can be distinguished 1... 

Ricin and Proteins The threat of a nuclear attack is one reason that Congress established the bipartisan Commission on the Prevention of Weapons of Mass Destruction Proliferation and Terrorism in 2007. In December 2008, the Commission issued World at Risk, a report that cautions that a weapon of mass destruction is likely to be used somewhere in the world before the end of 2013 unless action is taken immediately to forestall such an event.22 There are two major categories of weapons about which they are most concerned. Obviously, nuclear weapons in the hands of terrorists could kill enormous numbers of people, and the Commission agrees that the risk of a nuclear terrorist attack is increasing. However, they predict that it is more likely that terrorists will obtain and use a biological weapon first.23... 

The Centers for Disease Control and Prevention (CDC) Category A biological agents present unique threats to public health as well as to health care professionals who may care for patients exposed to these diseases. 

Explain the categories of threats from biological agents. 

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