Acquired immunity (aka passive immunity)
Host receives natural (from a nursing mothers breastmilk) or artificial (from an injection of immune serum) antibodies produced by another source.
Active immunity
Host produces antibodies in response to natural antigens (infectious microorganisms) or artificial antigens (vaccines).
Acute infection
Generally appear suddenly or last a short time.
Airborne precautions
Used for persons known to have or suspected of having serious illnesses transmitted by airborne droplet nuclei smaller than 5 microns. (Examples: Measles (rubeola), varicella (incl disseminated zoster), & TB.)
Antibodies (aka immunoglobulins)
Produced by B cells; part of the bodys plasma proteins; defend primarily against the extracellular phases of bacterial and viral infections.
Antigen
A substance that induces a state of sensitivity or immune responsiveness (immunity).
Antiseptics
Agents that inhibit the growth of some microorganisms.
Asepsis
The freedom disease-causing microorganisms; to decrease the possibility of transferring microorganisms from one place to another, aseptic technique is used.
Autoantigen
Proteins that originate in a persons own body.
Bacteremia
When a culture of a persons blood reveals microorganisms.
Bloodborne pathogens
Organisms in blood.
Carrier
Is a person or animal reservoir of a specific infectious agent that usually does not manifest any clinical signs of disease. (Example: mosquito carrying malaria but is unaffected by it).
Cell-mediated defenses (aka cellular immunity)
Occur through T-call system; on exposure to an antigen, the lymphoid tissues release large numbers of activated T-cells into the lymph system and then pass into general circulation. 3 types of T-cells: helper = help in functions of the immune system, cyto
Chronic infection
May occur slowly over a long period of time and may last months or years.
Humoral immunity (aka circulating immunity and/or antibody-mediated defenses)
Reside ultimately in the B lymphocytes and are mediated by antibodies produced by B cells.
Clean
Absence of almost all microorganisms.
Colonization
Process by which strains of microorganisms become resident flora and can grow and multiply but do not cause disease.
Communicable disease
Where infectious agents can be transmitted to an individual by direct or indirect contact or as an airborne infection.
Compromised host
A person at increased risk; who for one or more reasons is more likely than others to acquire an infection.
Contact precautions
Used for clients known or suspected to have serious illnesses easily transmitted by direct client contact or by contact with items in the clients environment.
Cultures
Labratory cultivations of microorganisms in a special growth medium (usually of urine, blood, sputum, or other drainage).
Dirty
Likely to have microorganisms; some of which may cause infection.
Disease
A detectable alteration in normal tissue function.
Disinfectants
Agents that destroy pathogens other than spores.
Droplet nuclei
the residue of evaporated droplets emitted by an infected host such as someone with TB.
Droplet precautions
Used for clients known to have or suspected of having serious illnesses transmitted by particle droplets larger than 5 microns (Examples: Diphtheria (pharyngeal), mycoplasma pneumonia, scarlet fever, & pneumonic plague).
Endogenous
When microorganisms that cause nosocomial infections originate directly from a sick patient.
Exogenous
When microorganisms that cause nosocomial infections originate from the hospital environment and/or hospital staff caring for sick patients.
Exudate
Fluid that escaped from the blood vessels, dead phagocyotic cells, and dead tissue cells and products that they release.
Fungi
Yeasts & molds.
Granulation tissue
Young connective tissue with new capillaries formed in the wound healing process.
Health care-associated infections (HAIs)
Those that originate in any healthcare setting.
Iatrogenic infections
Direct result of diagnostic or therapeutic procedures.
Specific defenses (aka immune defenses)
Directed against identifiable bacteria, viruses, fungi, or other infectious agents.
Immunity
A specific resistance of the body to infection; it may be natural, or resistance may develop after exposure to a disease agent.
Infection
Invasion of body tissue by microorganisms and their growth there.
Inflammation
Local and nonspecific defensive response of the tissues to an injurious or infectious agent.
Isolation
Measures designed to prevent the spread of infectious or potentially infectious microorganisms to health personnel, clients, and visitors.
Leukocytes
White blood cells.
Leukocytosis
Increased number of white blood cells.
Local infection
Limited to the specific part of the body where the microorganisms remain.
Medical asepsis
Includes all practices intended intended to confine a specific microorganism to a specific area, limiting the number, growth, and transmission of microorganisms.
Nonspecific defenses
Protect a person against all microorganisms, regardless of prior exposure.
Nosocomial infections
Classified as infections that originate in the hospital.
Occupational exposure
Defined as skin, eye, mucous membrane, or parenteral contact with blood or other potentially infectious materials that may result from the performance of an employees duties.
Opportunistic pathogen
Causes disease only in a susceptible individual.
Parasites
Live on other living organisms.
Pathogenicity
The ability to produce disease; thus , a pathogen is a microorganism that causes disease.
Regeneration
The replacement of destroyed tissue cells by cells that are identical or similar in structure and function.
Reservoirs
Sources of microorganisms.
Resident flora
The collective vegetation in a given area.
Respiratory hygiene/cough etiquette
Covering the mouth and nose when sneezing/coughing, proper disposal of tissues, and separating potentially infected persons from others by at least 1 meter (3 ft) or having them wear a surgical mask.
Sepsis
State of infection and can take on many forms, including septic shock.
Septicemia
When bacteria results in systemic infection.
Standard precautions (aka universal precautions)
The risk of caregiver exposure to client body tissues and fluids rather than the suspected presence or absence of infectious organisms determines the use of clean gloves, gowns, masks, and eye protection.
Sterile field
Microorganism-free area.
Sterilization
A process that destroys all microorganisms, including spores and viruses (Examples: moist heat, gas, boiling water, & radiation).
Surgical asepsis (aka sterile technique)
Refer to those practices that keep an area or object free of all microorganisms; it includes practices that destroy all microorganisms and spores. Used for all procedures involving the sterile areas of the body.
Systemic infection
Microorganisms spread and damage different parts of the body.
Vector-borne transmission
Transport of an infectious agent from an animal or flying or crawling insect that serves as an intermediate means via biting or depositing feces or other materials on the skin.
Vehicle-borne transmission
Transport of an infectious agent into a susceptible host via any intermediate substance (Examples: fomites or food).
Virulence
Ability to produce disease.
Viruses
Consist primarily of nucleic acid and therefore must enter living cells in order to reproduce.