Biological agents incubation periods

The time lag between exposure to a biological agent and the appearance of symptoms may serve as both a plus and a minus for terrorists. An incubation period allows terrorists time to attack and escape before an alarm is sounded. Conversely, an extended incubation period may diffuse the impact that the terrorists hope to achieve to bring attention to their causes (Tierno, 2002).2 The routes of exposure to biological agents vary, but may include ... 

Refer to Chapter 3 for specific details about individual biological agents including diseases caused, variations of the diseases, incubation periods, routes of exposure, transmissibility (person to person or otherwise), available vaccines, symptoms of exposure, and treatment methods. 

A chemical emergency occurs when a hazardous chemical has been accidentally or intentionally released and has the potential to harm the health of people (CDC, 2002a). Unlike biological agents, which require an incubation period before symptoms appear, a chemical agent, when released, makes its presence known im-... 

Unlike the other scenarios we have discussed, it may take days for a biological attack to be recognized and for the specific agent to be identified. The diseases biological agents cause each have their own timelines identification usually comes after the incubation period for the disease, which, in some cases, may be two weeks or more.5... 

Primary passage of three separate cases of vCJD killed Tg(BoPrP) 4125/Pm/>°/° mice with incubation periods of 250 to 270 days, comparable to that obtained with catde BSE and secondary passage of BSE from Tg(BoPrP)4125/Prw/>°/° mice (Scott et al, 1999). This is perhaps not surprising, as vCJD has been shown to share both the molecular and biological properties of the BSE strain. These data are in accord with the clear evidence that vCJD is caused by the same agent strain as BSE (Collinge etal., 1996 Bruce et al., 1997 Hill et al., 1997). However, the bovine to human species barrier, which is discussed further later, was not directly tested by Scott et al. (1999). 

Distinct prion isolates are referred to as strains. Strains of agent are defined and identified by their biological properties such as pattern of the incubation periods, lesion profile (the distribution of pathological change in the brain) in mice of defined PrP genotype (Bruce et al.,... 

This is an example of a biological attack using botulism toxin. Because of the incubation period before the victims developed symptoms, the banquet food had already been dumped in the local landfill before an investigation could begin. The medical responders were not affected because the agent was a toxin placed in food and not a contagious agent. 

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