| A | B |
| AIDS | The immune system has become weakened as a result of the action of the virus |
| Antibiotics | Medications capable of inhibiting the growth of or destroying microorganisms |
| Bacteria | One-celled plants and can be either pathogenic or nonpathogenic |
| Chain of infection | a useful model for explaining how infectious diseases occur and are transmitted |
| Fungi | Large group of simple plants |
| Hepatitis B | Virus infection is the major infectious blood-borne occupational hazard for health care workers |
| HIV positive | Humans infected with HIV |
| Infection control | Prevent the spread of infectious diseases |
| Microbes | Microorganisms that are pathogenic |
| Microbiology | The study of microorganisms |
| Neutropenic precautions | Isolation procedures to protect an immunocompromised patient from infections |
| Nosocomial infection | Infection that occurs while the patient is receiving in health care |
| Opportunistic infections | An infection accurs due to the weakened physiological state of the body |
| Parasite | An organism that nourishes itself at the expense of other living things and causes them damage |
| Pathogens | Disease-causing microorganisms |
| Protozoa | Microorganisms that are classified as animals |
| Rickettsia | A microorganism that is smaller than bacteria and has rod or spherical shapes |
| Standard precautions | Practices designed to reduce the risk of transmission of microorganisms from both recognized and unrecognized sources of infection in health care settings |
| Transmission-based precatutions | Includes three types of isolation procedures required for specific infections |
| Viruses | The smallest of the microbes and cannot be seen under the traditional light microscope |