RAD 110 Infection Control, Aseptic and Patient-Care Techniques: Chapters 17–19

What is an infection?

Establishment and growth of a microorganism on or in a host.

When does an infection become a disease?

When it causes injury or damage to the host.

What is a pathogen?

A disease-producing microorganism.

What are the four major infectious agents?

Bacteria, viruses, fungi, and protozoan parasites.

Are bacteria prokaryotic or eukaryotic?

Prokaryotic; they lack a nucleus.

What are the three basic bacterial shapes?

Cocci (spheres), bacilli (rods), and spirals.

What is Gram staining used for?

Differentiating bacteria based on cell-wall staining characteristics.

What is a bacterial endospore?

A highly resistant resting form that may survive for years.

What is an obligate intracellular parasite?

An organism that requires living host cells to replicate; viruses are examples.

What genetic material does a virus carry?

DNA or RNA, but not both in one viral genome.

What is a virion?

A complete viral particle.

Why do antibiotics not treat viral infections?

Antibiotics target bacterial processes, not viral replication.

Are fungi prokaryotic or eukaryotic?

Eukaryotic; they have nuclei and membrane-bound organelles.

What does dimorphic mean for pathogenic fungi?

Able to grow in yeast and mold forms.

What are conidia?

Fungal spores that can disperse to new habitats.

What does a superficial fungal infection usually affect?

The outermost skin surface, often causing discoloration.

What tissues do cutaneous fungal infections affect?

Keratinized skin, hair, and nails.

How do subcutaneous fungal infections commonly enter?

Through trauma or a break in the skin.

What characterizes a systemic fungal infection?

Spread into deeper tissues or body systems; potentially serious.

What are protozoa?

Single-celled eukaryotes that lack a cell wall.

What four movement categories are used for protozoa?

Amoeboid, flagellated, ciliated, and nonmotile sporozoans.

Why do some protozoa form cysts?

To survive unfavorable conditions outside a host.

What are the six stages of infectious disease establishment?

Encounter, entry, spread, multiplication, damage, outcome.

What happens during encounter?

A microorganism contacts a potential host.

What happens during entry?

The microbe enters through ingestion, inhalation, wounds, or another route.

What happens during spread?

The organism disseminates within the host.

What happens during multiplication?

The organism increases in number within the host.

What is direct microbial damage?

Cell destruction or harm caused directly by the organism or its toxins.

What are three possible infection outcomes?

Elimination, disease, or persistent coexistence with the host.

What four factors does your course list for transmission?

Host, infectious agent, mode of transmission, and reservoir.

What is exogenous transmission?

Introduction of organisms from outside the body.

What is endogenous transmission?

Infection arising from organisms already present on or in the body.

What is a vector?

A living carrier such as a mosquito, tick, or flea.

What is a fomite?

An inanimate object capable of transferring microorganisms.

What is a reservoir?

A site where an infectious organism survives and can be transmitted.

What is an asymptomatic carrier?

A person harboring an organism without displaying disease symptoms.

What is colonization?

Presence of microorganisms without necessarily causing disease.

What does HAI stand for?

Healthcare-associated infection.

What does nosocomial mean?

Acquired in a hospital setting.

What does iatrogenic mean?

Caused by a medical intervention or treatment.

What is a common catheter-associated HAI?

Urinary tract infection (CAUTI).

Name four major categories of HAIs.

Urinary tract, surgical site, bloodstream, and pneumonia infections.

Why are hospitalized patients vulnerable to opportunistic pathogens?

Impaired defenses and invasive devices can allow microbes to flourish.

What organ does hepatitis B primarily affect?

The liver.

Which immune cells does HIV primarily infect?

CD4-positive T lymphocytes.

What is normal flora?

The microbial community ordinarily present on or in a healthy person.

What is phagocytosis?

Engulfment and destruction of foreign material by phagocytes.

Name two chemical defenses against microbes.

Lysozyme in tears/urine and acidic stomach secretions.

What does bacteriostatic mean?

Inhibits bacterial growth without directly killing bacteria.

What does bactericidal mean?

Kills susceptible bacteria.

What is the purpose of a vaccine?

To stimulate an immune response and active immunity.

What does CDC stand for?

Centers for Disease Control and Prevention.

What does OSHA stand for?

Occupational Safety and Health Administration.

What is the WHO?

World Health Organization.

What is medical asepsis?

Reducing microbial numbers and transmission risk; not achieving sterility.

What is surgical asepsis?

Maintaining a sterile environment to prevent microbial contamination.

What is sterilization?

A process intended to eliminate all viable microorganisms, including spores.

What is a disinfectant?

A chemical used to reduce or inactivate microbes on inanimate surfaces.

What is an antiseptic?

An antimicrobial product applied to living tissue.

What is an autoclave?

A device that sterilizes using pressurized steam (moist heat).

What standard steam-sterilization example was highlighted?

121°C (250°F), 15 psi, for 15 minutes; depends on load and cycle.

Why is moist heat often more effective than dry heat?

It transfers heat efficiently and kills microbes more rapidly.

What is the most important routine action for limiting infection spread?

Appropriate hand hygiene.

To whom do standard precautions apply?

Every patient, regardless of known infection status.

When should gloves be used under standard precautions?

When contact with blood, body fluids, mucosa, or nonintact skin is anticipated.

What should happen to used needles?

Discard promptly into an approved sharps container; do not recap routinely.

What is PPE?

Personal protective equipment: gloves, gowns, masks, eye/face protection, etc.

What is the purpose of transmission-based precautions?

To prevent the spread of infections.

What room is typically used for airborne precautions?

A negative-pressure airborne infection isolation room.

What respiratory protection is associated with airborne precautions?

A fit-tested N95 or higher-level respirator.

Name three diseases commonly associated with airborne precautions.

Tuberculosis, measles, and varicella (chickenpox).

What is the main route of droplet transmission?

Respiratory droplets released by coughing, sneezing, or talking.

Name three diseases listed for droplet precautions.

Influenza, mumps, and rubella.

What is the main route of contact transmission?

Direct contact or indirect contact with contaminated surfaces/items.

What hand hygiene is emphasized for C. difficile care?

Soap and water, especially after contact with spores.

What does MRSA stand for?

Methicillin-resistant Staphylococcus aureus.

What does VRE stand for?

Vancomycin-resistant enterococci.

What does CRE stand for?

Carbapenem-resistant Enterobacterales.

What is a key distinction between contamination and infection?

Contamination is the presence of microbes; infection involves establishment and growth.

What are the two goals of aseptic technique?

Protect patients from infection and prevent pathogen transmission.

Name four imaging procedures that may require sterile technique.

Angiography, arthrography, myelography, and biopsies.

What is a sterile field?

A designated area maintained free of viable microorganisms.

What is commonly used to establish a sterile field?

A sterile drape.

When should a sterile package be rejected?

If wet, damaged, opened, or expired.

What part of a sterile wrapper is considered nonsterile?

The outer one-inch border.

How should sterile package flaps be opened?

Open away and around the field; never reach across it.

How are sterile supplies added to a sterile field?

Drop gently from about 6 inches above at a slight angle.

What happens if a sterile item touches an unsterile surface?

It is considered contaminated and must be replaced.

What happens to sterile items held below waist level?

They are considered contaminated.

Why is moisture a threat to a sterile field?

Strikethrough can carry microbes from an unsterile surface.

What part of a draped sterile table is considered sterile?

The top surface at table level, not hanging edges.

Why should movement and talking over a sterile field be limited?

To reduce airborne contamination and droplets.

What is a sterile corridor?

The protected area between the patient drape and sterile instrument table.

What should be verified before pouring sterile solution?

Solution identity, expiration date, and container integrity.

Why should splashing sterile solution be avoided?

Moisture can compromise the sterile drape or field.

What are three goals of a surgical hand scrub?

Remove debris/transient flora, reduce resident flora, slow regrowth.

What are two surgical scrubbing methods?

Timed method and numbered-stroke method.

Which gown surfaces are considered sterile?

The front above waist level and designated sleeve areas.

How should two sterile-gowned people pass each other?

Back to back, as described in the course material.

What is closed gloving?

Applying sterile gloves while hands remain within gown sleeves.