Microbiology: A Systems Approach 4th Edition by Marjorie Kelly Cowan

Exercise 12

Critical thinking is the ability to reason and solve problems using facts and concepts. These questions can be approached from a number of angles and, in most cases, they do not have a single correct answer.
a. Explain why the nervous system is described as "immunologically privileged," and discuss whether this provides a beneficial or disadvantageous effect in this system.
b. Discuss the defenses a pathogen encounters as it attempts to gain entry into the nervous system.