Airborne precautions: Transmission-based precautions used for clients with diagnosed or suspected pathogens spread by very small airborne particles from nasal and oral secretions that can float long distances through the air, such as measles and tuberculosis.

Blood-borne pathogens: Infectious microorganisms in blood and body fluids that can cause disease, including hepatitis B (HBV), hepatitis C (HCV), and human immunodeficiency virus (HIV).

Carrier: An individual who is colonized with an infectious agent.

Chain of infection: The process of how an infection spreads based on six links of transmission: Infectious Agent, Reservoir, Portal of Exit, Modes of Transmission, Portal of Entry, and Susceptible Host.

Colonization: A condition when a person carries an infectious agent but is not symptomatic or ill.

Contact precautions: Transmission-based precautions used for clients with known or suspected infections transmitted by touch such as C-difficile (C-diff), methicillin-resistant staphylococcus aureus (MRSA), vancomycin resistant enterococcus (VRE), or norovirus.

Disinfection: The removal of microorganisms. However, disinfection does not destroy all spores and viruses.

Doff: Take off personal protective equipment (PPE).

Don: Put on personal protective equipment (PPE).

Droplet precautions: Transmission-based precautions used for clients with a diagnosed or suspected pathogen that is spread in small droplets from sneezing or in oral and nasal secretions, such as influenza or pertussis.

Eye protection: Face shields, visors attached to masks, and goggles that are used to protect the eyes from blood or body fluids.

Fever: A temperature of 38 degrees Celsius (100.4 degrees F).

Hand hygiene: The process of removing, killing, or destroying microorganisms or visible contaminants from the hands. There are two hand-hygiene techniques: handwashing with soap and water and the use of alcohol-based hand rub (ABHR).

Healthcare-associated infection (HAI): An infection that develops in an individual after admission to a health care facility or undergoing a medical procedure.

Infection control: Methods to prevent or stop the spread of infections in health care settings.

Infectious agent: Microorganisms, such as bacteria, viruses, fungi, or parasites that can cause infectious disease.

Inflammation: Redness, warmth, swelling, and tenderness associated with early signs of infection.

Isolation gowns: Protective garments worn to protect clothing from the splashing or spraying of body fluids and reduce the transmission of microorganisms.

Malaise: A feeling of discomfort, illness, or lack of well-being that is often associated with infection.

Masks: Protective coverings worn by health care providers to protect the mucous membranes of their nose and mouth.

Medical asepsis: Techniques used to prevent the transfer of microorganisms from one person or object to another but do not completely eliminate microorganisms.

Mode of transmission: The way an infectious agent travels to other people and places.

Moments of hand hygiene: Appropriate times during patient care to perform hand hygiene, including immediately before touching a patient; before performing an aseptic task; before moving from a soiled body site to a clean body site; after touching a patient or their immediate environment; after contact with blood, body fluids, or contaminated surfaces (with or without glove use); and immediately after glove removal.

Nonspecific defenses: Generic barriers that prevent pathogens from entering the body, including physical, mechanical, or chemical barriers.

PAPR: An air-purifying respirator that uses a blower to force air through filter cartridges or canisters into the breathing zone of the wearer. This process creates an air flow inside either a tight-fitting facepiece or loose-fitting hood or helmet, providing a higher level of protection against aerosolized pathogens.

Perineal care: Cleansing the genital and rectal areas of the body.

Personal protective equipment (PPE): Specialized clothing or equipment used to prevent the spread of infection, including gloves, gowns, facial protection (masks and eye protection), and respirators.

Portal of entry: The route by which an infectious agent enters a new host.

Portal of exit: The route by which an infectious agent escapes or leaves the reservoir.

Purulent drainage: Yellow, green, or brown drainage associated with signs of infection.

Reservoir: The host in which infectious agents live, grow, and multiply.

Respirator masks: Masks with N95 or higher filtration worn by health care professionals to prevent inhalation of infectious small airborne particles.

Respiratory hygiene: Methods to prevent the spread of respiratory infections, including coughing/sneezing into the inside of one’s elbow or covering one’s mouth/nose with a tissue when coughing and promptly disposing of used tissues. Hand hygiene should be immediately performed after contact with one’s respiratory secretions. A coughing person should also wear a surgical mask to contain secretions.

Specific defenses: Immune system processes like white blood cells attacking particular pathogens.

Standard precautions: Precautions used by health care workers during client care when contact or potential contact with blood or body fluids may occur based on the principle that all blood, body fluids (except sweat), nonintact skin, and mucous membranes may contain transmissible infectious agents. These precautions reduce the risk of exposure for the health care worker and protect patients from potential transmission of infectious organisms.

Sterilization: A process used on equipment and the environment that destroys all pathogens, including spores and viruses. Sterilization methods include steam, boiling water, dry heat, radiation, and chemicals.

Surgical asepsis: The absence of all microorganisms during any type of invasive procedure; used for equipment used during invasive procedures, as well as the environment.

Susceptible host:  A person at elevated risk of developing an infection when exposed to an infectious agent.

Transmission-based precautions: Specific types of personal protective equipment (PPE) and practices used with clients with specific types of infectious agents based on the pathogen’s mode of transmission.