Determination of ID₅₀ Should Correlate Well with LD₅₀ UNLESS

Question

Determination of ID₅₀ should correlate well with LD₅₀ UNLESS:
A)the virus was systemic
B)the cells used in the cell culture approach were from an organism not usually infected with the virus
C)test animals provided the cells used in the culture approach
D)ethical concerns influenced the course of the experimental approaches
E)none is a valid choice

Accepted Answer

The ID₅₀ (Infectious Dose 50) is a measure of the amount of virus needed to infect 50% of a population, while the LD₅₀ (Lethal Dose 50) measures the amount of virus needed to kill 50% of a population. These two measures should correlate well unless the cells used in the cell culture approach were from an organism not usually infected with the virus (choice B). This is because the virus may not interact with these cells in a typical manner, leading to inaccurate ID₅₀ measurements that do not correlate well with LD₅₀ values obtained from more relevant systems.