Foundations in Microbiology 9th Edition by Kathleen Park Talaro, Barry Chess

Exercise 3

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.
Why do some tests for antibody in serum (such as for HIV and syphilis) require backup verification with additional tests at a later date?