Table 15.1 $$\begin{array} { | l | l | l | }
\hline \text { Bacterium } & \text { Portal of Entry } & \text { D50 } \
\hline \text { Staphylococcus aureus } & \text { Wound } &

Question

Table 15.1 $$\begin{array} { | l | l | l | } 
\hline \text { Bacterium } & \text { Portal of Entry } & \text { D50 } \
\hline \text { Staphylococcus aureus } & \text { Wound } & < 10 \
\hline \text { Staphylococcus aureus } & \text { Wound + Ampicillin } & 300 \
\hline
\end{array}$$
Table 15.1 shows the ID₅₀ for Staphylococcus aureus in wounds with and without the administration of ampicillin before surgery.Based on the data,the administration of ampicillin before surgery
A)decreases the risk of staphylococcal infection.
B)increases the risk of staphylococcal infection.
C)has no effect on risk of infection.
D)replaces tetracycline.
E)The answer cannot be determined based on the information provided.

Quizplus · Accepted Answer

The D50 (infectious dose for 50% of the population) for Staphylococcus aureus in wounds is less than 10 without ampicillin and 300 with ampicillin. This suggests that the administration of ampicillin before surgery decreases the risk of staphylococcal infection as it increases the infectious dose required for 50% of the population to be infected.

Table 151 Table 151 Shows the ID₅₀ for Staphylococcus Aureus in Wounds with |