Agents of Bioterrorism: Pathogens and Their Weaponization

Joseph Patrick Ward

Maria E. Garrido

As of early 2003, people thought that a new virus spreading throughout the world faster than the Internet could happen only in bad dreams or modern science-fiction movies. Then we learned about SARS-CoV, the virus that causes severe acute respiratory syndrome (SARS). Less than 7 months after it was first reported, SARS had taken the lives of approximately 800 people and infected a total of more than 8400 people worldwide.

SARS-CoV belongs to the family of coronaviruses. The coronaviruses (order Nidovirales, family Coronaviridae, genus Coronavirus) are members of a family of large, enveloped, positive-sense, single-stranded RNA viruses that replicate in the cytoplasm of host cells. Coronaviruses are highly species-specific, and the family had only included two human-infecting viruses prior to the discovery of SARS-CoV. Coronaviruses are divided into three groups, and exactly where SARS-CoV fits into the three groups has been debated. It has even been suggested that SARS-CoV represents a new, fourth group of coronaviruses.

No vaccine or effective treatment currently exists for SARS.¹¹ The natural host has not yet been identified despite widespread speculation that the host is the civet, a cat-like mammal from which a virus similar to SARS-CoV has been isolated. Because of the circumstances surrounding the SARS outbreak of 2003 and the very small number of cases that have been reported since, it has been proposed that the 2003 outbreak was strictly a one-time event. Although much research was conducted during and immediately after the 2003 outbreak, little research has been done on the disease and its causative agent in the latter half of 2004. The disease-control community is in disagreement about whether time and money should be committed to studying SARS in the face of limited resources and many other infectious agents that appear to be more of a threat.

No one can definitively declare that another large SARS outbreak will not occur in the future. There were four cases in January 2004 in the same Pearl River Delta region of China where the 2003 outbreak began. In April 2004,

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