Chapter 17. Infection Control Review

If there is a colonization can you assume that there is a disease present?

No. Disease implies tissue damage and related symptoms.

Fomite

Object, such as a book, wooden object, or article of clothing, that is not in itself harmful but is able to harbor pathogenic microorganisms and thus may serve as an agent of transmission of an infection.

_____ microorganisms cause infectious diseases.

Pathogenic

Nosocomial

Pertaining to or originating in the hospital; said of an infection not present or incubating before admittance to the hospital but generally developing 72 hours after admittance.

Standard Precautions

Precautions to prevent the transmission of disease by body fluids and substances. Standard precautions should be used when performing procedures that may require contact with blood, body fluids, secretions, exertions, mucous membranes, and non intact skin. Aslo included int his category are items soiled or contaminated with any of these substances.

Standard precautions

Precautions to prevent the transmission of disease by body fluids and substances. -Manage ALL patients as though they were potentially infectious -Based on the concept of the use of barriers = all contact with all substances, on all patients at all times.

Surgical Asepsis

Procedure used to prevent contamination by microbes and endospores before, during, or after surgery using sterile technique.

Surgical Asepsis

Procedure used to prevent contamination of microbes and endospores before, during and after surgery using sterile technique.

Bacteria

Prokaryotic, ubiquitous, single-celled organisms. Are microscopic, single-celled organisms with a simple internal organization.

Medical Asepsis

Reduction in numbers of infectious agents, which, in turn, decreases the probability of infection but does not necessarily reduce it to zero.

Iatrogenic

Resulting from the activities of physicians. EX: a patient may develop pneumonia after the performance of a lung biopsy by a physician.

Immunity

Security against a particular disease.

Constitutive defenses of the body:

Skin, mucous membranes, normal microbial flora, chemotherapy, and immunization.

Cyst

Stage in the life cycle of certain parasites during which they are enclosed in a protective wall. Resistant to chemical and physical changes.

Protozoa

Subkingdom comprising the simplest organisms of the animal kingdom, consisting of unicellular organisms that range in size from submicroscopic to macroscopic; most are free living, but some lead commensalistic, mutualist, or parasitic existences.

Vaccine

Suspension of attenuated or killed microorganisms (bacteria, viruses, or rickettsiae) administered for the prevention, improvement, or treatment of infectious disease. A mixture used to induce active immunity( the production of antibody).

Spread

The site of microbial entry or the site where the microbe has taken up residence and the human anatomy at the site determine the spread of the microbe. EX: The viruses that cause the common cold are easily spread as aerosols through coughing and sneezing.

Reservoir

The site where the infectious organism can remain alive and transmission can occur. -people, animals, and inanimate objects -Carrier- person who serves as a reservoir

Pathogenic fungi

They are dimorphic- that is, they have the ability to grow in two distance forms, either as a single celled yeast or as filamentous hyphae (mold).

Chemotherapy

Treatment of disease by chemical agents.

With in the United States, recommendations and guidelines for environmental control of infectious diseases are issued by who? and who enforces the established policies?

U.S. Department of Health and Human Services (HHS) and the Centers for Disease Control and Prevention (CDC). The U.S. Department of Labor's Occupational Safety and health Administration (OSHA).

The best method of preventing the spread of aerosol infections is by: a. the patient wearing a mask b. the health care worker wearing a gown c. hand washing d. all of the above

a. the patient wearing a mask

A person is bitten by a mosquito and develops an infection. This type of transmission is known as: a. vector b. fomite c. nosocomial d. iatrogenic

a. vector

transmission-Based Precautions

applied whenever a patient is infected with a pathogenic organism or a communicable disease. Isolation techniques.

Nosocomial

-A specific type of infection that is acquired from a hospital stay. -Most common: UTI*****

Formite

-An object that comes in contact with an infectious organism. -Examples: contaminated urinary catheter, x-ray table, calipers, hands, book, clothing.

Host

-Animal or plant that harbors another organism -People who have a reduced resistance to infection (patients).

Disease

-Any deviation from or interruption of the normal structure or function of any part, organ, or system (or combination thereof) of the body -Caused by microorganisms -absence of health

Fungi

-Can be macroscopic (ex. Mushrooms) or Microscopic (yeast and molds) -larger than bacteria

Vector

-Carrier (animal), that transfers an infective agent from one host to another. -examples: Mosquitoes, fleas, dogs/cats, rats, bats, squirrels.

Pathogens

-Disease producing microorganism 3 functions: 1) multiply in large numbers and cause obstruction 2) cause tissue damage 3) secrete exotoxins (exotoxins cause: temperature, nausea, or shock).

Blood-borne Pathogens

-Disease-causing microorganism that may be present in human blood. (HAIs) -HBV and HIV

Infection

-Establishment and growth of a microorganism on or in a host, resulting in injury to the host -Caused by pathogenic organisms -Exotoxins cause side effects

Asepsis

-Freedom from infection -surgical and medical -microbes survive at 37 degrees C (98.6 F)

Asepsis Physical Methods

-Moist heat is most commonly used for sterilization -steam under pressure (121 degrees C at a pressure of 15 lb/in(squared) for 15 minutes) -Autoclave= heat and steam pressure sterilization -use of barriers: gloves, gowns, masks.

Hand washing

-chemical and physical process -7-8 minutes of washing required -use friction -before and after each patient

Diseases caused by fungi:

1) superficial infection= causes discoloration of the skin. 2) cutaneous infection= involves hair, nails, or skin (ex. Tinea pedis or athletes foot) 3) subcutaneous fungal infections= enter the host as a result of trauma to the skin. 4) systemic infection= fungus enters the circulatory and lymphatic systems and may be fatal.

A health care worker is accidentally punctured with a contaminated needle. This type of transmission is known as: a. vector b. fomite c. nosocomial d. iatrogenic

b. fomite

The common cold is an example of an infection by a: a. bacterium b. virus c. fungus d. protozoan

b. virus

An infection microbe can gain entrance into the human body by: a. ingression b. penetration c. both a and b d. neither a or b

c. both a and b

Microorganisms that cause infectious disease can be classified as: a. lytic b. endogenous c. pathogenic d. nosocomial

c. pathogenic

Although bacteria are single called, they may reside int he host in group or cluster called a _____.

colony.

Hand washing employs which of the following methods of infection control? a. chemical b. physical c. sterile d. a and b

d. a and b

An outpatient develops a Staph infection after a surgical procedure. This type of transmission is known as: a. vector b. fomite c. nosocomial d. more than one of the above, but not all

d. more than one of the above, but not all

The term that best describes the absolute removal of all life forms is: a. antisepsis b. medical asepsis c. disinfection d. sterilization

d. sterilization

All of the following are types of indirect transmission except: a. fomite b. vector c. aerosol d. touching

d. touching

Only when the _____ results in injury to the host is the host said to have a _______.

infection. disease.

Endogenously Acquired diseases

the result of encounters with organisms already present in or on the body, the normal flora. This transmission usually happens when normal flora of a specify area is transported to a different area. EX: staphylococci on the surface of the skin can invade deeper tissue through a laceration. In this case, the initial encounter with staph may have been years earlier, but the infection was initiated as a result of the trauma.

Pathogens are divided into what four basic infectious agents?

1. Bacteria. 2. Viruses. 3. Fungi. 4. protozoan parasites.

Carrier

A person who serves as a reservoir. An infected person who does not display the disease symptoms.

Medical Asepsis

A reduction in numbers of infectious agents, which in turn decreases the probability of infection but does not necessarily reduce it to zero. -practice good housekeeping- change sheet on table after each patient

Sterilization

Absolute killing of all life forms

Reservoir

Alternative or passive host or carrier that harbors pathogenic organisms, without injury to itself, and serves as a source from which other individuals can be infected. EX: 1. Cow- some disease can be passed from the cow to a human host through the ingestion of milk. Pasteurization has helped obliterate most of these pathogens. 2. Insects- mosquitos, malaria.

Antiseptic

An disinfectant that is applied topically.

Entry

An infectious microbe can gain entrance into the human body by either ingression or penetration. Ingression doesn't involve deep-tissue penetration. These microorganisms adhere to the surface of the cell and excrete toxins that cause a distressed state within the system. The most common example of a symptom caused by an ingressive organism is diarrhea. Penetration involves the microorganism invading past the epithelial barrier.

Host

Animal or plant that harbors or nourishes another organism.

Asepsis Chemical Methods

Antiseptic= disinfects topically -Bacteriostatics =stops the growth of bacteria -Bactericidal= kills the bacteria -Chlorine bleach= 10:1 water/bleach ratio -Iodine/ betadine solution to disinfect the skin before procedures.

Virus

Any of a group of minute infectious agents not resolved in the light microscope and characterized by a lack of independent metabolism and the ability to replicate only within living host cells. -Latent or dormant

Viruses

Any of a group of minute infectious agents not resolved in the light microscope, with certain exceptions (e.g., poxvirus), and characterized by a lack of independent metabolism and by the ability to replicate only within living host cells. Neither prokaryotic nor eukaryotic. They're considered obligate intracellular parasites. Cannot live outside a living cell because they lack the components necessary for their own survival because of their inability to synthesize specific required proteins. Viruses depend on the host cell to provide these missing factors.

What are some examples of environmental control?

Asepsis, chemical methods, physical methods, hand washing, standard precautions, gloving, PPE.

Endospore

Bacteria that have the ability to produce a highly resistant resting form. Metabolically dormant structures that are highly resistant to the external environment.

Why are some chemotherapeutic drugs termed -cidal? Ex: bactericidal drugs.

Because of their ability to kill susceptible microbes. EX: penicillins

Why are some chemotherapeutic drugs termed -static? For example: bacteriostatic drugs.

Because they inhibit growth but do not cause killing.

Vector

Carrier, especially an animal (usually an arthropod), that transfers an infective agent from one host to another. EX: deer tick, transmits lyme disease.

Disinfectants

Chemicals used to free an environment from pathogenic organisms or to render such organisms inert, especially as applied to the treatment of inanimate materials to reduce or eliminate infectious organisms.

Sterilization

Complete destruction or elimination of all living microorganisms, accomplished by physical methods (dry or moist heat), chemical agents (ethylene oxide, formaldehyde, alcohol), radiation (ultraviolet, cathode), or mechanical methods (filtration).

Virion

Complete viral particle found extracellularly and capable of surviving in crystalline form and infecting a living cell; comprises the nucleoid ( genetic material) and the capsid; also called viral particle.

Damage

Damage can be either direct or indirect. Direct Example: Cell death caused by destruction of the host cells or by toxins or poisons secreted by the infectious agents. in a matter of hours enough organisms may be present to cause a complete obstruction in major organ system. Indirect Example: altering the metabolism of the host. These infections are represented by some of the most life threatening diseases.

Diseases

Deviations from or interruptions of the normal structure or function of any part, organ, or system (or combination of thereof) of the body that are exhibited by a characteristic set of symptoms and signs and whose cause, pathologic mechanism, and prognosis may be known or unknown.

4 routes of infection:

Direct contact, formite, vector, airborne

Bloodborne Pathogens

Disease-causing microorganisms that may be present in human blood.

Pathogens

Disease-producing microorganisms.

Alcohol kills endospores. True or False?

False

Explain the chain of infection:

Four factors are involved in the spread of diseases. Each factor is considered a link in the chain, and each link is connected to the next to form a ring. if at any point in the infection the chain is broken, the cycle cannot continue, and infection will cease. For infections to be transmitted, they following must exist: 1. A host. 2. an infectious microorganism. EX: bacteria, fungi, viruses, protozoa 3. a mode of transportation. 4 a reservoir

Asepsis

Freedom from infection. Can be decided into two categories: surgical asepsis and medical asepsis.

Exogenously acquired diseases

From outside the body. exogenously acquired diseases are those that result from an encounter with a microbe in the environment. This transmission can occur by either direct or indirect host to host contact. indirect transmission may also occur through a vector or a fomite.

Fungi

General term used to denote a group of eukaryotic protists- including mushrooms, yeasts, rusts, molds, and smuts- that are characterized by the absences of chlorophyll and by the presence of a rigid cell wall. Much larger than bacteria.

What disinfectants are common in the radiology department?

Halogens chlorine and iodine. They are both bactericidal.

Biosafety in the radiology department using standard precautions includes, but is not limited to, the following guidelines:

Hand washing- must wash before and after patient regardless if gloves were worn.. Gloving. PPE- i.e. gloves, eyewear, masks. Needle Recapping. Biospills. Transmission-Based Precautions. Airborne precautions. Droplet precautions. Contact precautions. Contact precautions technique.

What are the two bloodborne pathogens are of concern within the hospital setting?

Hepatitis B Virus (HBV).- affects the liver HIV- affects immune system CD4 and T cells

Airborne

Infection that is spread by droplets in air or dust (coughing or sneezing)

Health Care-Associated infection (HAI)

Infection that patients acquire while they are receiving treatment for another health care issue. Infections that people acquire while they are receiving treatment for another condition while in a health care setting. Nosocomial and iatrogenic infections.

Health care-associated infections (HAIs)

Infections that people acquire while they are receiving treatment for another condition while in a health care setting. -known as nosocomial infections

Robert Koch

Introduced the germ theory of disease in 1976. He was able to prove that specific organisms caused specific diseases. He was able to prove that a precise series of events must occur for microorganisms from an infected person to be transmitted to an uninfected person. His postulates forever changed the relationship between microorganisms and humans.

Infection

Invasion and multiplication of microorganisms in body tissues that may be clinically inapparent or may result in local cellular injury as a result of competitive metabolism, toxins, intracellular replication, or antigen-antibody response. Refers to the establishment and growth of a microorganism on or in a host.

Pasteurization

Involves moderate heating followed by rapid cooling

Encounter

Involves the infectious organism coming in contact with the host. Every individual and every microbe will respond differently. The initial encounter with infectious microorganisms takes place during the normal birthing process. some examples of Congenital infections that can be passed through the placenta are rubella, and syphilis.

Modern immunology began with the experiments of who?

Louis pasteur

What are essential to life through their ability to recycle organic and inorganic matter and are devastating through their ability to produce disease?

Microbes

At the beginning of the twentieth century, the major causes of death in the United States were ______ ______ ______.

Microbial Infectious Diseases. EX: Pneumonia, tuberculosis, gastroenteritis, and diphtheria.

Flora

Microbial community found on or in a healthy person. When a person is healthy, the relationship between the host and the microbe is either beneficial or neutral; but when this person is compromised, the microbe seizes the opportunity to flourish and is harmful.

Microorganisms

Microscopic organisms; those of medical interest include bacteria, viruses, fungi, and protozoa. Can grow in or on a host organism and causes disease. These disease are known as infectious.

Bacteria

Microscopic, single-celled organisms with a simple internal organization.

Physical methods to environmental control:

Moist heat is much more effective and rapid at killing than dry heat. Moist heat involves using steam under pressure which is accomplished in a divide called an autoclave.

Multiplication

Most infectious agents must first multiply for their impact to be recognized. The first time frame applied to this phenomenon is termed the incubation period, and its parameters are defined from the time the host's defenses have been overcome until the time a substantial population has been achieved.

The establishment of an infectious disease is a six-step process. What are these steps?

1. Encounter. 2. Entry. 3. Spread. 4. Multiplication. 5. Damage. 6. Outcome

microorganisms can be transmitted by what two ways?

1. Exogenously- from outside the body. 2. Endogenously- from inside the body.

Diseases caused by fungi can be of four different classifications. What are they?

1. Superficial infection- usually causes discoloration of the skin. I.E.: Tinea nigra- a fungal infection that results in a painless black or brown discoloration of the palmar surface of the hand and the plantar surface of the foot. 2. Cutaneous infections- involve the keratinized tissues of the hair, nails, and skin. I.E.: Tinea Pedis (athletes foot, ringworm). 3. Subcutaneous infections- Enters the human host as a result of trauma to skin. 4. Systemic Infection- enters the circulatory and lymphatic systems and may be fatal.

An encounter with an infectious agent can result in one of three outcomes. What are they?

1. The host gains control of the infectious agent and eliminates it. 2. The infectious agent overcomes the host's immunities to cause disease. 3. The host and the infectious agent compromise and live in a somewhat anxious state of symbiosis.

Pathogens have the ability to do one of the three functions extremely well. What are they?

1. They can multiply in large numbers and cause an obstruction. 2. They can cause tissue damage. 3. They can secret organic substances called exotoxins. These exotoxins can produce certain side effects such as an extremely high body temperature, nausea, vomiting, or shock.