Microorganisms: Helpful or Harmful?

Dear Researchers,

Today is your day to shine! A local doctors office had a small collection of microorganisms that they were saving for testing. The doctor's office needs your assistance, as a professional in answering the following question, "Which microorganisms are helpful and which ones are harmful?" Somehow, the microorganisms were released and they have contacted you to get them back. First, you must learn all about the different microorganisms that have escaped. Many of these microbes are helpful to you, but beware! Some can also be harmful. After learning all about the different microbes who have mysteriously disappeared, you will chose one to create a wanted poster about. On your poster, you will advertise that there is a cash reward associated with the capture and return of the microbe. You will then write a persuasive essay answering the question above, letting the doctor know that you are a professional on your chosen microbe, and that you know whether this microbe is helpful or harmful. 

Good luck!