INFECTION CONTROL

UNIVERSAL PRECAUTIONS

GLOVES SHOULD BE WORN WHEN YOU ARE IN CONTACT WITH

BLOOD, BODY FLUIDS CONTAINING VISIBLE BLOOD, MUCOUS
MEMBRANES, OR NONINTACT SKIN
GLOVES SHOULD BE WORN WHEN YOU ARE HANDLING ITEMS OR
TOUCHING SURFACES SOILED WITH BLOOD OR BODY FLUIDS OR
WHEN PERFORMING VENIPUNCTURE OR OTHER VASCULAR
ACCESS PROCEDURES
GLOVES SHOULD BE CHANGED AFTER CONTACT WITH EACH
PATIENT
 UNIVERSAL PRECAUTIONS

 MASKS AND PROTECTIVE EYE SHIELDS SHOULD BE WORN DURING

PROCEDURES THAT VAN GENERATE DROPLETS OF BLOOD OR OTHER
BODY FLUIDS, TO PREVENT EXPOSURE OF MUCOUS MEMBRANES OF
THE MOUTH NOSE EYES TO INFECTION
 GOWNS SHOULD BE WORN DURING PROCEDURES THAT CAN RESULT
IN THE SPLASHING OF BLOOD OR OTHER BODY FLUIDS
 HANDS AND OTHER SKIN SURFACES SHOULD BE THOROUGHLY
WASHED IMMEDIATELY AFTER CONTAMINATION WITH BLOOD OR
BODY FLUIDS
 UNIVERSAL PRECAUTIONS

NEEDLES SHOULD NOT BE RECAPPED PURPOSELY BENT OR

BROKEN OR REMOVED FROM SYRINGES
NEEDLES AND SYRINGES MUST BE DISPOSED OF IN PUNCTURE-
RESISTANT CONTAINERS IN THE IMMEDIATE WORK AREA
MOUTHPIECES, AMBU BAGS AND VENTILATION DEVICES SHOULD
BE USED RATHER THAN MOUTH TO MOUTH RESUSCITATION
HEALTH CARE WORKERS WITH OOZING OR OPEN SORES SHOULD
REFRAIN FROM DIRECT CONTACT AND HANDLING OF PATIENT
CARE EQUIPMENT OR ITEMS
NOSOCOMIAL INFECTION (HAI)
 INFECTIONS ACQUIRED IN THE COURSE OF MEDICAL CARE
IATROGENIC INFECTION
 A NOSOCOMIAL INFECTION THAT RESULTS FROM A PARTICULAR TREATMENT
OR THERAPEUTIC PROCEDURE
COMMUNITY ACQUIRED INFECTION
 AN INFECTION ACQUIRED BY A PERSON BEFORE ENTERING A HEALTH CARE
FACILITY
 FACTORS THAT ENCOURAGE
NOSOCOMIAL INFECTIONS

 ENVIRONMENT ( CONTAMINATED AIR, FOOD AND INSTRUMENTS, OTHER PATIENTS WHO

HAVE ARE INFECTED, HOSPITAL PERSONNEL
 THERAPEUTIC REGIMEN ( IMMUNISUPPRESIVE AND CYTOTOXIC DRUGS USED TO TREAT
MALIGNANT AND CHRONIC DISEASES; ANTIOMICROBIAL THERAPY WHICH MAY ALTER THE
NORMAL FLORA OF THE BODY AND ENCOURAGE THE GROWTH OF RESISTANT STRAINS OF
MICROBES)
 EQUIPMENT (CATHETERS, INTRAVENOUS TUBING, CANNULAS, RESPIRATORY THERAPY
EQUIPMENTS, GI TUBES THAT HAS NOT BEEN ADEQUATELY CLEANED AND STERILIZED
 CONTAMINATION DURING MEDICAL PROCEDURES ( MICROBES DURING DRESSING
CHANGES, CATHETER INSERTION, OR ANY INVASIVE PEOCEDURE MAY INTRODUCE
INFECTIVE ORGANISMS IF CORRECT TECHNIQUE IS NOT USED
FACTORS THAT INCREASE THE POTENTIAL
FOR NOSOCOMIAL INFECTION
FACTORS THAT INCREASE THE POTENTIAL
FOR NOSOCOMIAL INFECTION
FACTORS THAT INCREASE THE POTENTIAL
FOR NOSOCOMIAL INFECTION
FACTORS THAT INCREASE THE POTENTIAL
FOR NOSOCOMIAL INFECTION
PATHOGEN

CAUSATIVE AGENTS
MICROORGANISMS CAPABLE OF
PRODUCING DISEASE
OPPORTUNISTIC
RESERVOIR OF INFECTION

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
PORTAL OF EXIT

ANY PATHWAY BY WHICH PATHOGENS MAY BE

ABLE TO LEAVE THE RESERVOIR
URINE, FECES, BLOOD, RESPIRATORY DROPLET
SUSCEPTIBLE HOST

DIMISHED NATURAL RESISTANCE TO INFECTION

POORLY NOURISHED, WEAK, FATIGUED, SICK,
INFIRMED, IMNNOCOMPROMISED, YOUNG,
ELDERLY
PORTAL OF ENTRY

 PATHWAY BY WHICH INFECTIOUS ORGANISMS GAIN ENTRY TO THE

BODY
 SKIN BREAKS, GI TRACT, MUCOUS MEMEBRANES OF EYES, NOSE,
MOUTH, RESPIRATORY AND URINARY TRACT
 INGESTION, INJECTION, INHALATION
 PLACENTA
MODES OF TRANSMISSION

DROPLET
AIRBORNE
CONTACT
FOMITE

 AN 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
VECTOR

A CARRIER, ESPECIALLY AN ANIMAL (USUALLY AN

ARTHROPOD), THAT TRANSFERS AN INFECTIVE
AGENT FROM ONE HOST TO ANOTHER
MOSQUITO, FLEA, TICK
INFECTIOUS PATHOGENS
4 MAJOR GROUPS OF MICROORGANISMS
THAT ARE KNOWN PRODUCE DISEASES

BACTERIA
FUNGI
VIRUSES
PARASITES
ESCHERICHIA COLI (E. COLI)
STAPHYLOCOCCI
BACTERIA

 COLORLESS MINUTE ONE CELLED ORGANISM WITH A TYPICAL

NUCLEUS
 PROKARYOTIC RATHER THAN EUKARYOTIC ORGANISMS.
PROKARYOTES LACK A NUCLEUS AND MEMBRANE-BOUND
ORGANELLES, WHEREAS EUKARYOTES HAVE A TRUE NUCLEUS.
 THEY CONTAIN DNA ( CARRIES THE INHERITED CHARACTERISTICS OF
A CELL) RNA (CONSTRUCTS PROTEIN IN RESPONSE TO THE DIRECTION
OF DNA)
CLASSIFICATIONS:
CLASSIFICATIONS:
CLASSIFICATIONS:
Some bacteria have the ability to produce a highly resistant
resting form known as an endospore. This structure is internal, as
reflected in its name. Endospores are metabolically dormant
structures that are highly resistant to the external environment.
Spores possess extreme resistance to chemical and physical
agents. They can remain viable for many years and then
germinate in response to specific requirements. The endospore is
a survival form of the bacterium that is most often produced in
response to nutritional deprivation. Of all the bacteria able to
produce endospores, only two genera, Bacillus and Clostridium,
are of medical importance. Among the common bacterial
infections encountered today are streptococcal pharyngitis
(“strep throat”), Klebsiella pneumoniae infection (bacterial
pneumonia), and Clostridium botulinum infection (food
poisoning).
VIRUS

 A VIRUS IS A SMALL COLLECTION OF GENETIC CODE, EITHER DNA OR RNA, SURROUNDED BY

A PROTEIN COAT. A VIRUS CANNOT REPLICATE ALONE. VIRUSES MUST INFECT CELLS AND
USE COMPONENTS OF THE HOST CELL TO MAKE COPIES OF THEMSELVES.
 ARE MUCH SIMPLER IN FORM THAN BACTERIA OR ANIMAL CELLS. VIRUSES ARE NEITHER
PROKARYOTIC NOR EUKARYOTIC; THEY ARE CONSIDERED OBLIGATE INTRACELLULAR
PARASITES. VIRUSES CANNOT LIVE OUTSIDE A LIVING CELL. 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. A VIRUS CARRIES ITS OWN GENETIC INFORMATION IN THE FORM OF
DEOXYRIBONUCLEIC ACID (DNA) OR RIBONUCLEIC ACID (RNA), BUT NEVER BOTH. A
PROTEIN COAT CALLED A CAPSID SURROUNDS THE VIRAL DNA OR RNA.
VIRUS

 Viruses are generally characterized by the chemical nature of their nucleic acid, their size,
and their symmetry. Nucleic acids within a virus are, as stated earlier, either DNA or RNA,
but these nucleic acids may be double or single, positively or negatively stranded. Nucleic
acids of differing viruses also possess varying weights. The size of a virus may vary from 20
to 250 nm. A nanometer is equal to 10 −9 m; therefore direct observation of a virus is
possible only through an electron microscope.
 Viral infection is the result of a viral particle, also called a virion, which attaches to a host
cell and inserts its genome or genetic information into the host. The viral genome then
redirects the host cell. The virus uses the organelles and metabolic functions of the host
cell to produce new viruses. Once this process is completed, the new viral particles are
released from the host cell, sometimes resulting in destruction of the cell. Some viruses
have the ability to travel within the nervous system.
VIRUS

 They reappear sporadically and emerge at the nerve ending,

causing various symptoms. They then leave the site and travel up
the nerve again. This pattern can be repeated several times and is
known as a latent or dormant infection. A cold sore caused by
herpes simplex virus is an example of a latent viral infection.
Common viral diseases in humans include the common cold
(caused by the rhinovirus), infectious mononucleosis (caused by the
Epstein-Barr virus), and warts (caused by the papillomavirus).
RICKETTSIAS, CHLAMYDIAS,
MYCOPLASMAS

GRAM NEGATIVE BACTERIA-LIKE MICROBES

SMALLER THAN BACTERIA AND DO NOT HAVE ALL THE
CHARACTERISTICS OF THE BACTERIA
USED TO BE CONSIDERED AS VIRUSES BECAUSE THEY ARE
TOO SMALL TO BE SEEN UNDER NORMAL MICROSCOPIC
CONDITIONS
 RICKETTESIAS – TRANSMITTED FROM ANIMAL TO ANIMAL BY THE BITE OF AN
INFECTED ARTHROPOD VECTOR
- ROCKY MOUNTAIN SPOTTED FEVER, TYPHUS

 CHLAMYDIA – TRANSFERRED BY DIRECT CONTACT BETWEEN HOSTS (SEXUAL

CONTACT)
- CAUSES INFECTIONS OF URETHRA, BLADDER OR SEXUAL
ORGANS
 MYCOPLASMAS – MAY BE PARASITIC OR FREE LIVING
-CAUSE PNEUMONIA, GENITOURINARY INFECTIONS
Lyme disease
a bacterial infection that is
spread through the bite of one
of several types of ticks
FUNGI

CELLS THAT REQUIRE AN AEROBIC ENVIRONMENT

TO LIVE AND REPRODUCE
CAN BE MACROSCOPIC, AS IN THE CASE OF
MUSHROOMS AND PUFFBALLS, OR MICROSCOPIC,
SUCH AS YEASTS AND MOLDS
FUNGI
 THEY ARE EUKARYOTIC ORGANISMS WITH A NUCLEUS AND MEMBRANE-
BOUND ORGANELLES. FUNGI CAN BE DISTINGUISHED FROM BACTERIA
BY THE FACT THAT INTRACELLULAR ORGANELLES CAN BE VISUALIZED
WITHIN THE FUNGAL CELL. FUNGAL CELLS DIFFER FROM ANIMAL CELLS
IN THE TYPE OF STEROL PRESENT IN THE CELL MEMBRANE; THE STEROL
PRESENT IN ANIMAL CELLS IS CHOLESTEROL.
 FUNGI ARE ALSO MUCH LARGER THAN BACTERIA. MEDICALLY
IMPORTANT PATHOGENIC FUNGI ARE DIMORPHIC—THAT IS, THEY HAVE
THE ABILITY TO GROW IN TWO DISTINCT FORMS, EITHER AS A SINGLE-
CELLED YEAST OR AS FILAMENTOUS HYPHAE. A FILAMENTOUS HYPHA IS
BETTER KNOWN AS A MOLD. WHETHER THE ORGANISM IS PRESENT IN
EITHER FORM DEPENDS ON THE GROWTH CONDITIONS. FUNGI ARE
CLASSIFIED ACCORDING TO THE TYPE AND METHOD OF SEXUAL
REPRODUCTION
FUNGI

 Diseases caused by fungi can be of four different classifications. The first is a

superficial infection, which usually causes discoloration of the skin. Tinea nigra is 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. Second are the
cutaneous infections, which involve the keratinized tissues of the hair, nails, and
skin. The most common clinical infection in this group is tinea pedis, or athlete’s
foot. The growth pattern of this fungus forms a ring and is also known as ringworm.
The third type is a subcutaneous fungal infection that enters the human host as a
result of trauma to the skin. The fourth type is characterized by a systemic
infection that enters the circulatory and lymphatic systems and may be fata
PROTOZOA

 unicellular organisms that are neither plants nor animals. They are
distinguished from bacteria by their greater size and by the fact that they
do not possess a cell wall. Protozoa are generally motile organisms and
are eukaryotic. They are able to ingest food particles, and some species
are equipped with rudimentary digestive systems.
 classified according to their motility. The first group is classified by its slow
cellular flowing, called ameboid locomotion. Few amebae are
pathogenic. The motility of the second group is facilitated by a long
flagellum, or protein tail. The third group moves by the action of numerous
short protein tails called cilia. Sporozoans constitute the fourth group. This
group is unique in that its members are nonmotile and, despite their
name, do not form spores as do bacteria and fungi.
PROTOZOA

 SOME PROTOZOA ARE ABLE TO FORM A CYST, WHICH PERMITS THEM

TO SURVIVE WHILE THEY ARE NOT WITHIN A HOST. CYSTS ARE
RESISTANT TO CHEMICAL AND PHYSICAL CHANGES. TYPICAL
PROTOZOAN INFECTIONS INCLUDE TRICHOMONAS VAGINALIS
INFECTION, A SEXUALLY TRANSMITTED DISEASE THAT INFECTS BOTH
MALE AND FEMALE HOSTS, AND PLASMODIUM VIVAX INFECTION
(MALARIA).
Transmission-Based Precautions

 AIRBORNE PRECAUTIONS
Pathogenic organisms that remain suspended in air for long periods on aerosol droplets or
dust include tuberculosis, varicella (chickenpox), and rubeola (measles). Patients infected
with pathogens that disseminate through the air are to be placed in a negative-pressure
isolation room with the door closed. Health care practitioners should wear respiratory
protection when entering the room. This type of respiratory protection should filter inspired air.
An infected patient leaving his or her room should wear a surgical mask, which filters expired
air.
Transmission-Based Precautions

 DROPLET PRECAUTIONS
When caring for patients who are infected with such pathogenic organisms as rubella,
mumps, influenza, and adenovirus, droplet precautions should be used. These pathogens
disseminate through large particulate droplets expelled from the patient during coughing,
sneezing, or even talking. The pathogens infect another person through contact with the
mouth, nasal mucosa, or conjunctiva. Patients infected with these pathogens are placed in
private rooms or with another patient who is infected with the same disease. The door can
remain open because large droplets typically travel 3 feet before dropping to the ground.
Health care practitioners should protect themselves by wearing surgical masks when within 3
feet of the patient. Special ventilation precautions are not necessary. The patient should
wear a surgical mask when leaving the room.
Transmission-Based Precautions

 CONTACT PRECAUTION
must be used when caring for a patient infected with a virulent pathogen that spreads by direct
contact with the patient or by indirect contact with a contaminated object, such as patient’s
dressings or bed rails. Conditions that require using contact precautions include methicillin-resistant
Staphylococcus aureus, hepatitis A, impetigo, varicella, and varicella zoster. This patient will be
housed in a private room or with another patient who is infected with the same disease. The health
care practitioner should properly don gloves before entering the room. The gloves are removed
and hands washed before the practitioner leaves the room. A gown should be worn if the
practitioner anticipates contact with the patient or his or her environment; the gown is removed
before the practitioner leaves the room. All radiographic equipment placed in the contaminated
environment should be cleaned with an antiseptic solution. When a patient requiring contact
precautions is sent to the radiology department, the patient must wear appropriate barriers. In
many cases the patient will wear a mask and an impervious gown. Staff in the department should
be notified before receiving the patient. All radiographic equipment should be decontaminated
with an antiseptic after the radiographic procedure is completed.
Contact Precautions Technique

 In many instances, a radiologic technologist is required to examine patients who are on

contact precautions. Maintaining contact precautions usually requires teamwork.
Acquiring the assistance of another health care provider is important. Contact
precautions are maintained by the following steps
1. Determine the correct number of cassettes needed for the examination. Place each cassette
into a protective bag, which may be either a plastic or cloth isolation bag. These bags should be
available in the radiology department.
2. Move the portable machine to the isolation room.
3. Locate the isolation supplies for the room.
4. Remove all ornamentation (including watch, rings, earrings) and place them in a pocket.
5. Put on a lead apron.
6. Wash your hands
7. Put on a clean gown, making sure it is sufficiently long to cover most of the uniform. Pick up the
gown from the inside near the armhole openings and gently shake it open. Put one arm in and
then the other. First tie the neck strings and then tie the waist strings.
8. Put on a mask, tying it securely, and then a cap. Goggles may also be worn if available.
9.Put on the gloves, which should be clean but need not be sterile.
10. Have the assistant put on a gown, gloves, and cap.
11. Enter the isolated area and explain to the patient who you are and what you are doing.
You will appear intimidating. A gentle word will go a long way at this point.
12. Position the patient and the cassette.
13. Have your assistant manipulate the machine and make the exposure.
14. Remove the cassette from behind the patient. Fold the edge of the protective bag back,
never touching the inside. Have your assistant remove the cassette, never touching the
outside. Place the covering into an appropriate container. Have your assistant remove the
portable equipment from the room.
15. Untie the waist ties of the gown.
16.Untie the neck strings of the gown and pull the gown forward and down from the shoulders. Pull
the gown off so that the sleeves are inside out and the front of the gown is folded inward. Avoid
touching the front of the gown. Discard it into an appropriate container.
17. Remove your gloves. Remove the first glove with the other gloved hand, never touching the
inside of the glove. Grasp the top of the glove and pull it inside out. Remove the other glove with
the exposed hand, touching the inside only. Discard into an appropriate container.
18. Remove the cap and the mask and discard them in an appropriate container.
19. Wash your hands.
20. Have your assistant follow the same protocol. Clean the portable equipment with an antiseptic.
21. Wash your hands one last time.
An appropriate contact
precautions technique. (A) Put on
a lead apron and then gown,
never touching the outside of the
gown with your hands. (B) Put on
a mask with eye shield if
recommended. (C) Put on a cap.
(D) Put on nonsterile gloves. (E)
Place each cassette in a
protective bag. (F) Position the
bagged cassette beneath the
patient.
(G) Remove the protective bag,
never touching the inside, while an
assistant removes the cassette
without touching the outside of the
bag. (H) Untie the gown at the
waist. (I) Turn the gown inside out
without touching the outside of the
gown, and place the gown in the
appropriate receptacle. (J) Remove
the gloves, turning them inside out.
(K) Remove the cap. (L) Remove
the mask.