Introduction to Microbiology; Medical Asepsis; Infection Control; Surgical Asepsis

Incubation Stage

the time between entry of an infectious agent and the onset of symptoms (2-3 weeks after chicken pox).

Prodromal Stage

the time from onset of nonspecific symptoms until specific symptoms begin to manifest (stage that a person with chicken pox can expect to see the first skin eruptions).

Illness Stage

the time when client has specific signs and symtoms.

Vaccination

An inoculation with a vaccine to produce immunity against specific diseases.

Infection

An invasion and multiplication of pathogenic organisms (infectious agents) in body tissue that results in injury to host.

Six "links" in the Chain of Infection:

Biological Agent, Reservoir or Source, Portal of Exit from Reservoir or Source, Mode of Transmission, Portal of Entry to Host, Susceptible Host.

Standard Precautions Apply to:

Blood; All bodily fluids, secretions, and excretions EXCEPT sweat, regardless of whether those fluids contain visible blood.

Pathogenicity

Ability of microorganism to produce disease

Virulenece

Frequency with which a pathogen causes disease; an invading organisms strength.

Standard Precautions

A set of guidelines to be used of all healthcare established by CDC; Preventative practices to be used in the care of ALL CLIENTS in health care facilities REGARDLESS of diagnosis or presumed infection status.

Systemic Infections

Affect entire body & involve multiple organs, such as AIDS.

Vector-borne Transmission

Agent is transferred to a susceptible host by animate objects such as mosquitoes, fleas, ticks, lice, and other animals. Spread diseases by transferring microorganisms on feet, wings, and bodies to food which a person eats. (lyme's disease, malaria, west nile virus).

Vehicle Transmission

Agent is transferred to a susceptible host by contaminated inanimate objects such as water, food, milk, drugs, and blood (Cholera - transmitted through contaminated drinking water; Salmonella - transmitted through contaminated meat).

Resident Flora

Always present, usually without altering clients health.

Diseases from Fungi are treated with:

Antifungal Medications.

Breaking the Chain of Infection: Between Mode of Transmission and Portal of Entry

Asepsis, barrier protection, proper hand hygiene, proper disposal of contaminated equipment and linens.

Five types of microorganisms that can be pathogenic:

Bacteria, Viruses, Fungi, Protozoa, Rickettsia.

Immunizations

Best and most effective means for preventing viral infections.

Obligate Anaerobes

Cannot survive in the presence of oxygen.

What environmental factors affect bacteria?

Changes in temperature and Nutrition.

Breaking the Chain of Infection: Between Portal of Exit and Mode of Transmission

Clean dressings on all wounds, Cover mouth and nose when sneezing/coughing, wear gloves, properly dispose of contaminated articles.

Breaking the Chain of Infection: Between agent and Reservoir

Cleansing, Disinfection, Sterilization

Common Viral Infections:

Common Cold, Influenza, Measles, Chicken Pox, Hepatitis B, Genital Herpes, HIV (treated with anti-viral medications).

Contagious Disease

Communicable diseases; Transmitted to many individuals quickly and easily.

Chain of Infection

Describes the development of an infectious process.

Common Bacterial Infections:

Diarrhea (e. coli), pneumonia, gonorrhea, meningitis, UTI's. (often treated with antibacterial agents).

Contact Transmission

Direct contact with infected person. Indirect contact with the infected person through a fomite (bedding, tissues, syringes) or close contact with contaminated secretions (STD's, Common viral infections such as cold, flu).

What happens when the balance of Resident Flora is upset?

Disease may occur.

Transient Flora

Episodic, and do not continually live on the skin. Acquired from direct contact with the organism (Staph aureus on the skin.)

Physical Agents

Factors in environment capable of causing disease. (Heat, radiation).

Fungi

Grow in single cells or in colonies. Obtain food from dead organic matter, living organisms. Most are not pathogenic and make up many of the body's normal flora.

Where can Fungi cause infections?

Hair, skin, nails, and mucous membranes.

What is the nurses most important practice to prevent the spread of infection?

Hand washing

Pathogens

Harmful or disease-producing microorganisms.

Carriers

Have infectious agent but symptom free.

Port of Entry

How and infectious agent enters the host.

Portal of Exit

How infectious agent leaves the reservoir. Includes all body orifices and skin discharges (Sputum, Semen, vaginal secretions, and urine, Saliva and feces, Blood, Draining wounds, Tears).

Formites

Inanimate objects contaminated with an infectious agent (dressing, bedpans, etc.).

Microorganisms

Individual living animal or plant that is so small it can be seen only with the aid of a microscope.

Opportunistic Infection

Infections can occur when a person's resistance is lowered.

Rickettsia

Intracellular parasites that need to be in living cells to reproduce. Spread by fleas, ticks, mites, and lice.

Biological Agents

Living agents that invade the host, causing disease. (Bacteria, Viruses)

Vectors

Living carriers of disease.

Breaking the Chain of Infection: Between Portal of Entry and Host

Maintain skin integrity, use sterile technique for client contacts, avoid needle sticks by properly disposing of sharps, NEVER recap dirty needles.

Protection

Such as spores, mutation, and development of drug-resistant strains.

Common Infections of Protozoa:

Malaria, Gastroenteritis, Vaginal Infections

Exogenous Microorganisms

Microorganisms from outside the body that cause infection. (Salmonella, Clostridium tetani, and Aspergillus)

Endogenous Microorganisms

Microorganisms present within the person's body that causes infection. (Staphylococcus epidermidis)

FLORA

Microorganisms that occur or have adapted to live in a specific environment.

Hand Hygiene

Most basic and effective infection-control measure to prevent and control transmission of infectious agents. Single most important nosocomial infections.

Modes of Transmission/Vehicle

Movement of infectious agent from reservoir/source through portal of exit to portal of entry of susceptible host.

Colonization

Multiplication of microorganisms on or within a host without resulting in cellular injury.

Are ALL bacteria's harmful and cause diseases?

No.

Inflammation

Nonspecific cellular response to tissue injury, caused by bacteria, trauma, chemicals, heat, etc.

Host

Organism that can be affected by agent.

Parasite

Organism that lives within or at the expense of another living creature.

Opportunistic

Organisms invades the body when resistance is lowered.

Endemic

Organisms that are present all or most of the time in and on the body.

Viruses

Organisms that can live only inside cells. They cannot get nourishment or reproduce outside cells. Much smaller than bacteria.

Susceptible Host

Person who has no resistance to an agent and thus is vulnerable to diseases (measles).

Compromised Host

Person whose normal body defenses are impaired and is therefore susceptible to infection. (AIDS, Chemotherapy Patient).

How is bacteria classified?

Physical Shape, Movement, Relationship to Oxygen, Gram Stain Reaction.

Reservoir or Source

Place where agent can survive.

Breaking the Chain of Infection: Between Reservoir and Portal of Exit

Proper Hygiene, Clean dressings, Clean linen, Clean equipment after each use.

Breaking the Chain of Infection: Between Host and Agent

Proper nutrition, exercise, immunization

Obligate Aerobes

Require oxygen for growth.

Three New Elements Added To Standard Precautions

Respiratory Hygiene and Cough Etiquette, Safe Injection Practices, Special Practices for Lumbar Puncture.

Irritability

Response to the environment.

Microbiology

Scientific Study of Microorganisms.

Protozoa

Single-celled parasitic organisms with ability to move. Obtain food from dead, decaying organic matter. Infection is spread through contaminated food, water, or through insect bites.

Bacteria

Small, one-celled microorganisms that lack a true nucleus or mechanism to provide metabolism.

How should all culture media start out?

Sterile.

Chemical Agents

Substances that can interact with body, causing disease. (Pesticides, Industrial Chemicals).

Airbrone Transmission

Suspectible host contacts droplets in the air. The longer the particle is suspended the more likely an infection will develop. Particle size influences the length of time the organism can remain airborne. (Measles, tuberculosis, chicken pox).

Reproduction

The ability to group together to form colonies or the ability of individual cells to become larger.

Motion

The ability to move from place to place.

Metabolism

The ability to utilize nutrients.

What effects every system and tissue in the body?

Viruses

Epidemic

When a large number of people in the same area are infected in a relatively short period of time.

When is a Culture and Sensitivity (C&S) ordered?

When infection is suspected or known.

Convalescent Stage

from the beginning of the disappearance of acute symptoms until client returns previous state of health.

Localized infections

limited to defined area or single organ with symptoms that resemble inflammation (redness, tenderness, swelling), such as cold sore.

Surgical Asepsis

practices that eliminate all microorganisms and spores from an object or area.

Medical Asepsis

practices used to reduce the number, growth, and spread of microorganisms.

Acquired Immunity

protects individual against future invasions of already experienced antigens.