8.2 Infection Control Flashcards
An object that has been in contact with pathogenic organisms is called a _____
fomite
a contaminated urinary catheter is a typical example
fomite
Other _____ in the radiology department might include the x-ray table, vertical bucky, image receptors, positioning sponges contaminated with infectious body fluids, or perhaps your contaminated gloves
fomites
is an arthropod in whose body an infectious organism develops or multiplies before becoming infective to a new host. The bite of such infected insects can transmit diseases to humans.
vector
mosquitoes that transmit malaria or dengue fever, fleas that carry bubonic plague
vector
ticks that spread Lyme disease or Rocky Mountain spotted fever
vector
is any medium that transports microorganisms
vehicle
Examples include contaminated food, water, drugs, or blood
vehicle
occurs either by dust that contains spores or by droplet nuclei, which are particles of evaporated droplets measuring 5 microns (micrometers, 0.001mm) or smaller containing microorganisms that remain suspended in the air for long periods
Airborne contamination
M. tuberculosis, rubeola, and the varicella viruses are examples of _____
airborne infections
can also be contracted through contact with the vesicles that form with these viruses
Varicella
often occurs when an infectious individual coughs, sneezes, speaks, or sings in the vicinity of a susceptible host
Droplet contamination
Involves contact of the mucous membranes of the eyes, nose, or mouth of a susceptible person with large droplets (greater than 5 micrometers) containing microorganisms
Droplet contamination
These particles do not remain suspended in the air and travel only short distances, usually 3 feet or less
Droplet contamination
examples include influenza, meningitis, diphtheria, pertussis, and the streptococcal pneumonia
Droplet contamination
The ______ formed by some bacteria are resistant to heat, cold, and drying and can live without nourishment
endospores
are responsible for serious but relatively uncommon diseases, such as tetanus, anthrax, and botulism
Spore-forming bacterial organisms
are transmitted to a host through inhalation, ingestion, or contact. The host provides the moisture, warmth, and nutrients that enable the endospore to germinate into a bacterial cell again
spores
active immunity
acquired resistance
Mechanical barriers such as intact skin and mucous membranes provide natural resistance
Natural Resistance
The mucous membranes of the respiratory, urinary, gastrointestinal, and reproductive systems secrete mucus, which traps foreign particles
Natural Resistance
Chemicals, such as lysozyme in the human tears and acids of the stomach, vagina, and skin, also help destroy invading microorganisms
Natural Resistance
The pH, salt content, and dryness of the skin limit the number of bacteria that will reside these, and beneficial normal flora prevent the overgrowth of undesirable organisms
Natural Resistance
in spite of these barriers, microorganisms do gain
access into the body. This occurs as a result of common daily activities, such as brushing one’s teeth and shaving. This invasion initiates our _____ line of defense, the inflammatory response
second
Inflammation increases blood flow to the site and permits the passage of flids and WBCs into the tissues to engulf and destroy the invading pathogen. This process is called _______
phagocytosis
Virus-infected cells produce ______
Interferons
small protein molecules that protect the uninfected cells from invasion by the original virus as well as others
Interferons
are species-specific and are currently being produced in laboratories for the treatment of herpes and chronic hepatitis B and C
Interferons
The state of being resistant to a specific infection is called ______
immunity
occurs because the body is able to distinguish itself from foreign protein substances that enter the body
Acquired immunity
Acquired immunity occurs because the body is able to distinguish itself from foreign protein substances that enter the body. These substances are called ______
antigens
are protein substances formed in response to specific antigens
Antibodies
They are produced by a specific WBC, the B-cell, which works with other WBC to destroy invading foreign substances and prevent reinfection by a particular antigen.
Antibodies
Because the body forms its own antibodies to the specific antigen, acquired immunity is ____ term
long
Occurs following an injection of preformed antibodies to a particular infection
Passive Immunity
This is the case when individuals are given pooled immune globulin before and after exposure to hepatitis A
Passive Immunity
human blood and antibodies pooled from the general population
pooled immune globulin
is temporarily immune to infections because of the antibodies that are passed from mother to fetus in utero
newborn
Passive immunity is ____ term
short
There are several nosocomial infections that greatly concern health care providers and their hospitalized patients because they are _____
multidrug-resistant
both contribute to surgical wound, urinary tract, and bloodstream infections
Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE)
MRSA
Methicillin-resistant Staphylococcus aureus
VRE
vancomycin-resistant enterococci
can also cause respiratory infections
Methicillin-resistant Staphylococcus aureus (MRSA)
Another type of nosocomial infection that is very common in the hospital environment is _____
Clostridium difficile colitis
a gastrointestinal infection that causes diarrhea
Clostridium difficile colitis
is a Gram-positive bacillus that is especially difficult to control because it is a spore-forming bacterium that is not eliminated by the usual routine methods of asepsis
Clostridium difficile
is an RNA retrovirus
HIV
HIV
Human Immunodeficiency Virus
are called retroviruses because they replicate in a “backward” manner, converting from RNA to DNA once they invade a host cell
RNA viruses
The virus has specificity for the receptors on CD4 lymphocytes, attaching to and invading these cells and becoming a permanent part of their genetic material.
RNA viruses
produces infected CD4 cells and additional HIV
Cell replication
also known as T cells, are white blood cells that fight infection and play an important role in your immune system
CD4
In the early stages on _____, there is usually a brief period of flulike symptoms, often followed by years without symptoms
infection
During the ______ phase, the virus is silently replicating in the body and decreasing the number of CD4 lymphocytes
asymptomatic
At the end of the asymptomatic period, before the full development of ______, the individual will experience night sweats, oral infections, weight loss, persistently enlarged lymph nodes, and low-grade fever
AIDS
The appearance of ____ is characterized by a low CD4 count ad the occurrence of multiple opportunistic infections and malignant diseases
AIDS
Routes of transmission are through sexual contact, contaminated blood or needles, fluids containing blood, or from mother to fetus via the placenta. Infection can also be transmitted to infants through breast milk
HIV and AIDS
The five common types of hepatitis are classified _____
A through E
are transmitted through food and water contaminated with feces
Hepatitis A and E
only exists as co-infection to Hepatitis B Virus
Hepatitis D
are bloodborne
Hepatitis B, C, and D
can be spread through contact with blood or blood products; contact with body fluids such as saliva, semen, and vaginal secretions; and through maternal-fetal contact
Hepatitis B
is primarily spread by contact with blood or
blood products
Hepatitis C
the risk for contracting this virus is greatest for persons with large or repeated percutaneous exposures to blood, such as IDUs, whose risk is 60%.
Hepatitis C
the risk is lowest for those who are subject to
sporadic percutaneous exposures, such as health care workers, whose risk following a needlestick is 1% to 2%
Hepatitis C
the risk is 15% to 20% for sexual transmission
and 5% to 6% for maternal-fetal transmission
Hepatitis C
is more infectious than hepatitis C, and
the risk of developing clinical hepatitis from a needle-stick with infected blood is as high as 30%
Hepatitis B
Although a needlestick injury is the most efficient method of transmitting the _____, another mode of transmission is through nonintact skin contact with
infected blood on environmental surfaces
Hepatitis B virus (HBV)
as been demonstrated to survive in dried blood on environmental surfaces for at least a week. This means
you can contract ___ if you have an open wound and
touch a contaminated surface
HBV
The manifestations of all forms of hepatitis are similar:
Jaundice, fatigue, abdominal pain, loss of appetite, nausea, vomiting, and diarrhea
is more of a silent infection
Hepatitis C
have the potential to develop into chronic infections and cirrhosis, although risk is greater with HCV
HBV and HCV
Following infection with ____, about 85% of individuals develop chronic infection, approximately 70% develop liver disease, 10% to 20% develop cirrhosis, and 1% to 5% develop liver cancer. These sequelae take place over a 10- to 20-year period
HCV
HBV vaccine is administered in a series of ____ injections
three
The second dose is given 1 to 2 months after the 1st and the third is given after 4 to 6 months after the 1st or at least 2 months after the second dose
HBV vaccine
Management of Occupational exposures to Bloodborne Pathogens
- If an accidental needlestick occurs or the skin is broken by contaminated object, allow the wound to bleed under the cold water and wash it with soap.
- If your eyes, nose, or mouth are splashed with a patient’s bodily fluids, rinse these mucous membranes with water
- You will also be advised by the medical provider about post-exposure prophylaxis (PEP) therapy following a puncture with a contaminated needle. If treatment if recommended, it should be administered within 2 hours of the blood exposure.
- For most HIV exposures that warrant PEP, a 4-week, two-drug regimen is recommended, and several drug options are available
PEP
Post-exposure Prophylaxis
Is a lung disease caused by the acid-fast bacillus Mycobacterium tuberculosis
Tuberculosis
also referred to as tubercle bacillus
Mycobacterium tuberculosis
is spread through airborne droplet nuclei that are generated when an infected person coughs or speaks. These particles are 1 to 5 micrometers in size. And are easily transmitted through the air
Pulmonary Tuberculosis
Within 2 to 10 weeks following infection, the body, aided by its immune system, begins walling off the infection, preventing its multiplication and spread. When walled off, the disease is inactive or dormant, but it can be reactivated at any time
Tuberculosis
Reactivation may occur when an individual’s immune response is weakened as it is in old age, illness, or malnutrition, or with immunosuppressant therapy involving drugs that decrease the body’s normal immune response
Tuberculosis
Symptoms of ____ disease include productive or prolonged cough, fever, chills, loss of appetite, weight loss, fatigue, and night sweats
active Tuberculosis
Disease for which _____ is currently authorized include cholera, diphtheria, infectious TB, plague, smallpox, yellow fever, viral hemorrhagic fevers, and SARS
quarantine
Under this system, all patients are treated as potential reservoirs of infection. The system is based on the use of barriers for all contacts with blood and certain body fluids know to carry bloodborne pathogens, rather than focusing on the isolation of the patient with diagnosed bloodborne disease
Universal Precautions (1985)
Emphasis is placed in blood and certain body fluids being potential sources of _____, regardless of diagnosis
infection
This system is focused on the use of barriers for all moist and potentially infectious body substances from all patients
Body Substance Precaution (1987)
Are designed to reduce the risk of transmission of unrecognized sources of bloodborne and other pathogens in health care institutions
Standard Precautions (1996)
Standard Precautions apply to:
- Blood
- All body fluids
- Secretions and excretions (except sweat), regardless of whether they contain visible blood
- Nonintact skin
- Mucous membranes
also reduce the risk of transmission from recognized sources of infection by
including precautions for three modes of transmission:
airborne, droplet, and contact. T
Standard Precautions
Deals with reducing the probability of infectious organisms being transmitted to a susceptible individual
Medical Asepsis
The process of reducing the total number of organisms is called ______ and can be accomplished at several levels
Microbial dilution
First step of Microbial dilution is _____, such as proper cleaning, dusting, linen handline, and hand hygiene techniques, can reduce the transmission of microorganisms
simple cleanliness measures
The second level of Microbial dilution is _____ and involves the destruction of pathogens by using chemical materials
disinfection
The third level of Microbial dilution is _____. This involves treating items with heat, gas, or chemicals to make them germ-free
Surgical asepsis, or Sterilization
is an easy and effective method to control the transmission of infections
Medically aseptic handwashing
There are several reasons attributed to the poor adherence to regular handwashing in health care facilities:
- inaccessibility to sinks,
- lack of time in between patients,
- lack of role models,
- the concern that handwashing is irritating to the skin and causes dryness
Hand hygiene is recommended use of a preparation in the form of a gel, rinse, or foam containing 60% to 95% isopropanol or ethanol alcohol
Alcohol-based hand rub
This technique is found to be very effective against many microorganisms (Gram-negative, Gram-positive, M. tuberculosis, fungi, and some viruses) including some MDR organisms
Alcohol-based hand rub
It will not destroy bacterial spores such as C. difficile and Bacillus anthracis
Alcohol-based hand rub
______ with
soap and water is still recommended to physically remove spores from the surface of contaminated ha
Handwashing
