Infectious dose 50 (ID50) is defined as
A) The number of microorganisms required to kill 50% of inoculated hosts
B) The number of microorganisms required to cause clinical disease in 50% of the inoculated hosts
C) The number of microorganisms required to infect 50% of the human population
D) The impact of infection with 50 microbial cells
Answer: B
Microbiology
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