In general, the optimal time for use of BW weapons is during the late night and early morning. It is during these hours that inactivation of biological aerosols by ultraviolet radiation is minimal. In addition, neutral or inversion conditions are most likely to be present at these times. The phenomenon of atmospheric inversion best allows an agent cloud to travel along the land surface. Difficulties in Detection.
Human beings are a sensitive, and in some cases the only, biodetector.
Early clinical findings may be nonspecific or atypical of the natural disease. Medical personnel maybe unable to differentiate natural disease from BW attacks. Considerable time may elapse following a BW attack before the extent of the exposure is appreciated. Following a BW attack, the disease pattern is likely to have characteristics that differ from those of a naturally-occurring epidemic. An understanding of disease ecology and epidemiology can be extremely useful in distinguishing natural outbreaks from those induced by biological weapons.