Define “infection.”
It is the invasion of a susceptible host by pathogens or microorganisms, resulting in disease. Entry and multiplication of organisms result in disease. If pathogens multiply and cause clinical signs and symptoms, the infection is Symptomatic. If clinical signs and symptoms are not present, the illness is termed Asymptomatic.
Define “colonization.”
Colonization occurs when a microorganism invades the host but does not cause infection.
What are the stages of an infection?
- Incubation – interval between the pathogen entering the body and the presentation of the first symptom.
- Prodromal stage – interval from onset of general symptoms to more distinct symptoms. During this time, the pathogen is multiplying.
- Illness stage – interval when symptoms specific to the infection occur.
- Convalescence – interval when acute symptoms disappear. Total recovery could take days to months. Risks of Infection
What is the most important technique to use in preventing and controlling transmission of infection?
Hand hygiene (Hand hygiene includes using an instant alcohol hand antiseptic before and after providing patient care, washing hands with soap and water when they are visibly soiled, and performing a surgical scrub. Handwashing is the act of washing hands with soap and water, followed by rinsing under a stream of water for 15 seconds. Soap, running water, friction)
What does it mean to be “Immunocompromised”?
Immunocompromised means having an impaired immune system.
Define “virulence.”
Virulence is the ability of a pathogen to invade and injure a host.
What are “aerobic bacteria”?
Aerobic bacteria require oxygen for survival and for multiplication sufficient to cause disease.
What are “anaerobic bacteria”?
Anaerobic bacteria thrive where little or no free oxygen is available.
What is “bacteriostasis”?
It is the prevention of growth and reproduction of bacteria.
What is meant by being “bacteriocidal”?
It is destructive to bacteria.
A patient is admitted to a medical unit for a home-acquired pressure ulcer. The patient has Alzheimer’s disease and has been incontinent of urine. The nurse inserts a Foley catheter. You will identify a link in the infection chain as A. Restraints. B. Poor hygiene. C. Foley catheter bag. D. Improper positioning.
C. Foley catheter bag.
List the types of pathogens.
- Bacteria (Staphylococcus aureus, Escherichia coli, Mycobacterium tuberculosis)
- Viruses – Organisms that use the host’s genetic machinery to reproduce (HIV, hepatitis, herpes zoster, herpes simplex)
- Fungi – Molds and yeasts (Candida albicans, Aspergillus)
- Prions – Protein particles (new variant Creutzfeldt-Jakob disease)
- Parasites – Protozoa (malaria, toxoplasmosis) and helminths (worms [flatworms, roundworms], flukes [Schistosoma])
What are the types of immune systems?
- Nonspecific innate
2. Specific adaptive
What comprises the “nonspecific innate” immune system?
Nonspecific innate: Native immunity restricts entry or immediately responds to a foreign organism (antigen) through the activation of phagocytic cells, complement, and inflammation. This occurs with all micro-organisms, regardless of previous exposure.
◯ Temporary immunity that does not have memory of past exposures
◯ Intact skin, the body’s first line of defense
◯ Mucous membranes, secretions, enzymes, phagocytic cells, and protective proteins
◯ Inflammatory response with phagocytic cells, the complement system, and interferons localize the invasion and prevent its spread
What comprises the “specific adaptive” immune system?
Specific adaptive immunity allows the body to make antibodies in response to a foreign organism (antigen). This reaction directs against an identifiable micro-organism.
◯ Requires time to react to antigens
◯ Provides permanent immunity
◯ Involves B- and T-lymphocytes
◯ Produces specific antibodies against specific antigens (immunoglobulins [IgA, IgD, IgE, IgG, IgM])
List the infection control practices.
medical asepsis, surgical asepsis, standard precautions
List the links that make the chain of infection.
- Infectious agent or pathogen.
- Reservoir or source for pathogen growth.
- Portal of exit.
- Mode of transmission.
- Portal of entry.
- Susceptible host
Name examples of “portals of exit.”
■ Respiratory tract (droplet, airborne) -Mycobacterium tuberculosis -Streptococcus pneumoniae ■ Gastrointestinal tract -Shigella -Salmonella enteritidis -Salmonella typhi -hepatitis A ■ Genitourinary tract -Escherichia coli -hepatitis A -herpes simplex virus (type 1) -HIV ■ Skin/mucous membranes -Herpes simplex virus -varicella ■ Blood/body fluids -HIV -hepatitis B and C
Name examples of “modes of transmission.”
■ Contact -Direct physical contact btwn persons -Indirect contact with an inanimate object -Fecal-oral transmission ■ Droplet -Sneezing, coughing -talking ■ Airborne -Sneezing and coughing ■ Vector borne -Animals or insects as intermediaries - for example, ticks transmit Lyme disease; mosquitoes transmit West Nile and malaria
Describe individuals who have compromised health or defenses against infection.
■ Those who are immunocompromised.
■ Those who have had surgery.
■ Those with indwelling devices.
■ A break in the skin (the body’s best protection against infection).
■ Those with poor oxygenation.
■ Those with impaired circulation.
■ Those who have chronic or acute disease such as diabetes mellitus, adrenal insufficiency, renal failure, hepatic failure, or chronic lung disease.
Why are older adults more at risk?
Older adults have a slowed response to antibiotic therapy, slowed immune response, loss of subcutaneous tissue and thinning of the skin, decreased vascularity and slowed wound healing, decreased cough and gag reflexes, chronic illnesses, decreased gastric acid production, decreased mobility, bowel and bladder incontinence, dementia, and greater incidence of invasive devices such as a urinary catheter or feeding tube.
What are Health-Care Associated Infections (HAIs)?
– These are infections that a client acquires while receiving care in a health care setting. Formally called nosocomial infections, these can come from an exogenous source (from outside the client) or an endogenous source (inside the client when part of the client’s flora is altered).
– The most common setting for HAIs is the intensive care unit.
– The best way to prevent HAIs is through frequent and effective hand hygiene.
– The most common site of HAIs is the urinary tract. The most common causative agents are Escherichia coli, Staphylococcus aureus, and enterococci. Other sites of HAIs are surgical wounds, respiratory tract, and bloodstream.
– An iatrogenic infection is a type of HAI resulting from a diagnostic or therapeutic procedure.
– HAIs are not always preventable and are not always iatrogenic.
– Use current evidence-based practice guidelines to prevent HAIs due to multidrug-resistant organisms. Assessment/Data Collection
List the signs and symptoms, identifiable in the nursing assessment, of generalized or systemic infection. (S/S of local inflammation and infection are identical.)
- Fever
- Presence of chills, which occur when temperature is rising, and diaphoresis, which occurs when temperature is decreasing
- Increased pulse and respiratory rate (in response to the high fever)
- Malaise
- Fatigue
- Anorexia, nausea, and vomiting
- Abdominal cramping and diarrhea
- Enlarged lymph nodes (repositories for “waste”)
- Atypical symptoms such as agitation, confusion, or incontinence
- Other symptoms may vary depending on the site of the infection (dyspnea, cough, purulent sputum, and crackles in lung fields, dysuria, urinary frequency, hematuria and pyuria, rash, skin lesions, purulent wound drainage, erythema and odynophagia, dysphagia, hyperemia, enlarged tonsils, change in level of consciousness, nuchal rigidity, photophobia, headache)
What is “inflammation”?
Inflammation is the body’s local response to injury or infection.
