I'm a microbiologist in a hospital lab. We work way off the radar. Most patients have a vague idea of "the lab" being the person who draws their blood, then puts it on a machine.
A couple weeks ago, we isolated and identified a somewhat obscure bacteria from a young man's blood. The infectious disease doctor was skeptical at first, since he didn't think the patient had the corresponding symptoms. Well, the patient was VERY ill and on a respirator in ICU. He DID have symptoms, but had gotten so sick so fast, the doctors hadn't been able to question him completely. Once the organism was treated correctly and the patient started to get better, it was realized that he did have an unusual case of meningitis. We were thrilled to have had such an important impact on this young man's recovery.
Today, I recieved a thank you note specifically written to the "Lab Technician who perservered until she recognized the bacteria that infected our son" from the parents. Wow! In 30 years of work, I have never been thanked so directly for the work I do. What a thrill! I love this job!