Table 15.2 $\begin{array}{|l|c|}
\hline \text { Bacterium } & \text { ID50 } \
\hline \text { E. coli } 0157: \mathrm{H7} & 20 \
\hline \text { Legionella pneumophia } & 1 \
\hline \text { Shigella } & 10 \\hline \text { Treponema pallidum } & 57 \
\hline
\end{array}$
-Which organism in Table 15.2 most easily causes an infection?
A) Shigella
B) Legionella pneumophila
C) Treponema pallidum
D) E. coli O157:H7
E) The answer cannot be determined based on the information provided.

Question

Quizplus · Accepted Answer

The ID50 value indicates the number of organisms required to cause infection in 50% of the host population. The lower the ID50, the more easily the organism can cause an infection. Legionella pneumophila has the lowest ID50 of 1, indicating it most easily causes an infection.

Table 152 -Which Organism in Table 15