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Transcript
CHAPTER
3
HIV, Hepatitis, and
Other Blood-Borne
Pathogens
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-2
Learning Outcomes
3.1
Describe ways in which blood-borne
pathogens can be transmitted.
3.2
Explain why strict adherence to Universal
Precautions is essential in preventing the
spread of infection.
3.3
Describe the symptoms of hepatitis and
AIDS.
3.4
List and describe the blood tests used to
diagnose HIV infection.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-3
Learning Outcomes (cont.)
3.5
Identify chronic disorders often found in
patients who have AIDS.
3.6
Compare and contrast drugs used to treat
AIDS/HIV infection.
3.7
Describe the symptoms of infection by other
common blood-borne pathogens.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-4
Learning Outcomes (cont.)
3.8
Describe the steps involved in reporting a
communicable disease.
3.9
Explain how to educate patients about
minimizing the risks of transmitting bloodborne infections to others.
3.10 Describe special issues you may encounter
when dealing with patients who have
terminal illnesses.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-5
Introduction
• Chapter 34 expands on OSHA BloodBorne Pathogen Standard
– How to reduce your risk of exposure
• HIV, hepatitis, and other blood-borne
infections
– Reporting guidelines
– Educating patients
• Issues associated with terminal illnesses
such as AIDS
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-6
Transmission of Blood-Borne Pathogens
• Blood-borne pathogens are diseasecausing microorganisms carried in the
host’s blood.
• Transmission occurs from one host to
another through contact with infected
– Blood
– Tissue
– Body fluids
– Mucous membranes
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-7
Transmission (cont.)

Transmission agents for blood-borne diseases






Blood
Blood products
Human tissue
Semen
Vaginal secretions
Saliva from dental
procedures
– Cerebrospinal fluid
– Synovial fluid
– Pleural fluid
– Peritoneal fluid
– Pericardial fluid
– Amniotic fluid
Identified by the Centers for Disease Control and Prevention (CDC)
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-8
Transmission (cont.)
• Transmission agent only if there is
visible blood
– Feces
– Nasal secretions
– Perspiration
– Tears
– Urine
– Vomitus
– Saliva
– Sputum
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-9
Transmission (cont.)
• Blood-borne pathogens
may be introduced into
a new host by
– Needlesticks
– Cuts or abrasions
– Any body opening
– Transfusion of infected
blood
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-10
People at Increased Risk
• Anyone who comes in contact with
substances that may harbor the pathogens
– Health-care professionals
– Law enforcement officers
– Mortuary or morgue attendants
– Firefighters
– Medical equipment service technicians
– Barbers and cosmetologists
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-11
People at Increased Risk (cont.)
• Pathogens
– Hepatitis B virus (HBV)
– Hepatitis C virus (HCV)
– HIV  AIDS
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-12
Research
• Incidence of many infectious
diseases
– Reported to state health
departments
• Information then sent to CDC
– Trends in spread
– Identify control tactics
– Allocate resources
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-13
Good
Answer
!
Apply Your Knowledge
How are blood-borne pathogens transmitted from
host to host?
ANSWER: Transmission occurs from one host to
another through contact with infected blood, tissue, body
fluids, and mucous membranes.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-14
Universal Precautions
•
The most effective means
of preventing the spread of
HIV, hepatitis, and other
blood-borne pathogens is to
avoid contamination
•
Universal Precautions are
required by OSHA
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-15
Universal Precautions
• For medical offices, includes all
– Body fluids
– Secretions
– Excretions
– Moist body surfaces
• Assume every patient is
contaminated
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-16
Apply Your Knowledge
In a medical office, to what items do Universal
Precautions apply, and with which patients should
you practice these precautions?
ANSWER: In medical offices, Universal Precautions
apply to body fluids, secretions, excretions, and moist
body surfaces. Assume every patient is contaminated
and use Universal Precautions with everyone.
Right!
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-17
Disease Profiles
• Keep up-to-date so you can
– Identify symptoms that may indicate that a
patient has a blood-borne disease
– Identify habits of your patients that increase
risk of spreading the disease
– Educate patients to limit risks of contracting
disease
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-18
Hepatitis
• Viral infection of the liver that can lead to
cirrhosis and death
– Hepatitis A – spread by fecal-oral route
– Hepatitis B – blood-borne disease that
spreads by contact with contaminated blood
or body fluids or sexual contact
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-19
Hepatitis (cont.)
– Hepatitis C (non-A/non-B)
• Spread through contact with contaminated
blood or body fluids and sexual contact
• No cure
• Many people are carriers
• Flu-like symptoms, if any
• Damages liver; causing cirrhosis, liver
failure, and cancer
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-20
Hepatitis (cont.)
– Hepatitis D (delta agent hepatitis)
• Occurs only in people that are infected with HBV
• May mimic symptoms of hepatitis B, but more
severe
• Associated with liver cancer
– Hepatitis E
• Caused by hepatitis E virus (HEV)
• Transmitted by fecal – oral route
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-21
Hepatitis (cont.)
• Risk factors – same for HBV and HCV
– Occupation that requires
exposure to blood and
body fluids
– Blood transfusions
prior to screen
– High-risk sexual activity
– Living with partner with
hepatitis B or hepatitis
C
– IV drug use
– Hemophilia
– Travel to areas with
high incidence
– Hemodialysis
– Multiple sexual
partners
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-22
Hepatitis (cont.)
• Risk in medical community
– HIV
• Approximately 0.5% from a single
needlestick
– Hepatitis B
• 6% to 33% from single needlestick
The primary risk factor for HBV and HCV infection is
occupational exposure to the virus.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-23
Hepatitis (cont.)
• Infection progression
– Acute illness lasts about 16 weeks
– Prodromal stage – general malaise,
maybe nausea or vomiting,
or no symptoms
– Icteric, or jaundice, stage – yellowing of
the skin, eyes, and mucous membranes
• Appears 5 – 10 days after initial infection
– Convalescent (after acute stages) – can
last 2 to 3 weeks
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-24
Hepatitis (cont.)
• Symptoms
–
–
–
–
–
–
–
Jaundice
Decreased appetite
Fatigue
Nausea and vomiting
Joint pain/tenderness
Stomach pain
General malaise
• Diagnosis
– Investigation of
• Risk factors
• Exposure incidents
– Blood tests
• Antigen-antibody
systems
• Determine stage of
disease
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-25
Hepatitis (cont.)
• Preventive measures
– Avoid contact with contaminated substances
– Use Universal Precautions with all patients
– Vaccination is available to prevent HBV
infections
• Will not protect you from other strains of hepatitis
• CDC recommends routine vaccination for
everyone
– HBIG for postexposure inoculation
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-26
AIDS/HIV Infection
• Virus that infects and destroys
components of the immune system
• HIV infection develops into AIDS
• Pathogen destroys
– Helper T cells – white blood cells that are a
key component of immune system
– Neurons, causing demyelination
• Patients develop opportunistic infections
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-27
AIDS/HIV Infection (cont.)
• Risk factors
– Unprotected sexual activity
– Sharing needles used by IV drug users
– Passes from mother to fetus during pregnancy or to
infant during delivery or breastfeeding
• Incubation period of 8 to 15 years
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-28
AIDS/HIV Infection (cont.)
• Risk in medical community
– Percutaneous exposure – exposure through
a puncture wound or needlestick
– Mucocutaneous exposure – exposure
through a mucous membrane
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-29
Progression of AIDS/HIV
• Three main stages
• Initial infection
– Can occur years before symptoms appear
– Virus enters cell and makes copies
– Helper T cells die
– Immune system responds
• Cleans the blood supply of the virus
• Virus enters an inactive phase
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-30
Progression of AIDS/HIV (cont.)
• Incubation period
– Virus genetic material incorporated into the
genetic material of the helper T cells
– HIV becomes active again and continues to
attack and kill helper T cells
– Virus trapped in lymph system
– As helper T cells decrease, patients are more
prone to opportunistic infections
– Incubation period can be 8 to 15 years
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-31
Progression of AIDS/HIV (cont.)
• Full-blown AIDS
– 200 or fewer helper T cells/mL blood indicates
full-blown AIDS
– Opportunistic infections and neurological
deterioration
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-32
Diagnosis of AIDS/HIV
• Enzyme-linked immunosorbent assay (ELISA)
– Confirms presence of antibodies in response to HIV
– 85% accurate – cross-reactivity with other viruses
• Western Blot Test or immunofluorescent antibody
(IFA)
– Confirms positive ELISA test
– Specific to individual viruses
• Accurate diagnosis – ELISA plus one of the other two
• Home tests available – may give false results
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-33
Symptoms of AIDS/HIV
• Systemic
• Respiratory
• Oral – hairy leukoplakia
• Gastrointestinal
• Peripheral nervous system
• Skin-related
• Kaposi’s sarcoma
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-34
Prevention of AIDS/HIV
• Sexual contact
– Use protection
– Avoid multiple partners
– Use condoms correctly
• IV drug users
– Avoid sharing or
reusing needles
• Medical procedures
– Universal Precautions
– Wash hands
• Education
– Dangers of HIV/AIDS
– How HIV/AIDS is
spread and not spread
– Preventive measures
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-35
Apply Your Knowledge
Which statements are true and which are false?
ANSWER:
T Risk factors are the same for HBV and HCV.
____
Right!
F Hepatitis A is spread via contaminated blood or body fluids.
___
Hepatitis A is spread by the fecal-oral route.
F Helper T cells are red blood cells and are a key component of
____
immune system. Helper T cells are white blood cells.
T Percutaneous exposure occurs through a puncture wound or
____
needlestick.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-36
Patient Profile
• No one is immune to AIDS
• 2005: 40.3 million men, women, and children
were HIV-infected worldwide.
• People infected
–
–
–
–
Homosexual males (rate decreasing)
Young people in large metropolitan areas
IV drug users
Women
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-37
Chronic Disorders of the AIDS Patient
• Impaired immune system permits
opportunistic infections
– Pneumocystis carinii pneumonia
• Protozoal infection
• Occurs in 75% of AIDS patients
– Kaposi’s sarcoma
• Aggressive malignancy
– Non-Hodgkin’s lymphoma
• Second most common malignancy associated with
HIV infection
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-38
Chronic Disorders (cont.)
– Tuberculosis
• Often drug-resistant
• Mantoux skin test often negative in AIDS patients
– Anergic reaction – no response to any substances
injected as a skin test
– Mycobacterium avium complex (MAC)
infections
• 97% of nontuberculous bacterial infections
– Meningitis
• Can lead to AIDS dementia complex
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-39
Chronic Disorders (cont.)
– Candidiasis
• Oral – thrush
• Vaginal – females
– Herpes simplex
• Infections caused by HSV can be mild to life-threatening
– Herpes zoster
• Virus that causes chickenpox becomes dormant
• Returns as herpes zoster, or shingles
• Lesions last longer in immunocompromised patients –
patients with impaired or weakened immune systems
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-40
Treating Opportunistic Infections
• Drug side effects problematic
• Patients develop
– Allergies to treatment
– Intolerance to medications
• Pathogens become resistant to
treatments
• Treatments may conflict with other
treatments
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-41
Testing Regulations
• CDC does not require
mandatory HIV
testing for health-care
workers
• Health-care workers’
chances of being
infected by a patient
are greater than a
patient being infected
by a health-care
worker
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-42
Drug Treatments
• Drugs
– Slow reproduction of
virus, no current cure
– List of FDA approved
drugs – Table 21-2
• Treatment goals
– Increase the time
between infection and
symptomatic disease
– Improve quality of life
– Reduce transmission
• To uninfected
• Maternal-infant
– Reduce HIV-related
deaths
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-43
Drug Treatments (cont.)
• Treatment guidelines
– Panel of Clinical Practices for Treatment of
HIV Infections
• Initial and follow-up testing
• Drug resistance testing
• HAART – combination of drug treatment
• Initiating therapy
– Decision made by patient and physician
– AIDS diagnosis or CD4 T cell count is <
200cells/mm3
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-44
Drug Treatments (cont.)
• Delayed treatment
– Benefits
• Postponement of drug-related adverse affects
• Delaying development of drug resistance
• Preserving treatment options
– Risks
• Irreversible immune system damage
• Increased risk of transmission of disease
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-45
Drug Treatments (cont.)
• Early treatment
– Benefits
– Disadvantages
• Suppression of viral
replication (preserves
immune function)
• Drug toxicity
• Reduction in chance of
transmission
• Adverse effects on
quality of life
• Helps patient live
symptom-free longer
• Loss of treatment
options
• Drug resistance
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-46
Drug Treatments (cont.)
• Treating
complications
– Must also treat
opportunistic infections
– Patients more prone to
•
•
•
•
•
• Continuing research
– Global issue
– Keep informed of new
treatments and
prevention methods
Bacterial infections
Protozoal infections
Viral infections
Fungal infections
Malignancies
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-47
Apply Your Knowledge
Identify where these opportunistic infections affect the body.
ANSWER:
1.
Herpes simplex
2.
Pneumocystis carinii
3.
Kaposi’s sarcoma
4.
Tuberculosis
5.
Meningitis
6.
Oral candidiasis
mouth, lips, genitalia
lungs
arms, legs, chest, neck,
face, conjunctiva, palate
lungs
brain
mouth, tongue
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-48
Other Blood-Borne Infections
• Cytomegalovirus
– Antibodies found in 80% of
adults
• Erythema infectiosum
– Parvovirus B19
– Fifth disease
• Human T-cell
lymphotropic virus
– HTLV-1
– Appears in IV drug users,
among others
• Listeriosis
– Caused by bacteria Listeria
monocytogenes
– Fever, shock, rash, and
aches
All are problematic for people with impaired immune systems.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-49
Other Blood-Borne Infections (cont.)
• Malaria
– Parasite enters
bloodstream through
mosquito’s bite
– Cyclical symptoms
• Toxoplasmosis
– Caused by
Toxoplasma gondii in
cat feces
• Syphilis
– Caused by spirochete
Treponema pallidum
– Three stages
– Difficult to identify and
treat in HIV-positive
persons
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-50
Apply Your Knowledge
Which blood-borne pathogen is found in 80% of
adults and rarely causes noticeable symptoms?
ANSWER: Cytomegalovirus (CMV)
Good Job!
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-51
Reporting Guidelines
• Requirements for reporting HIV
infections and AIDS determined
by state
• Follow state and employer’s
guidelines for reporting
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-52
Reporting Guidelines (cont.)
• State health department report forms
– Different for each disease
– Information needed
•
•
•
•
Disease identification
Patient identification
Infection history
Information about reporting institution
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-53
Apply Your Knowledge
What information is generally needed when making
a report of an infectious disease?
ANSWER: Information needed includes:
 Disease identification
 Patient identification
 Infection history
 Information about reporting institution
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-54
Patient Education
• An effective means of
preventing disease
transmission
• Assess the patient’s
understanding of the
risk for infection
• Provide information
about preventions
and treatments
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-55
Patient Education (cont.)
• Clinical drug trials
– Recognized research protocols designed to
• Evaluate the efficacy or safety of drugs
• Produce scientifically valid results
– Information on trials available from
www.ClinicalTrial.gov
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-56
Patients with Special Concerns
• Teenagers
– Dangers of HIV and AIDS
– Establish trust and provide facts
• Patients about to be discharged
– Patient must understand the importance of
• Returning for follow-up
• Reporting any adverse reactions
• Watching for signs and symptoms that need to be reported
• Multicultural concerns
– High-risk groups based on CDC reports
– Written information available in appropriate language
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-57
Apply Your Knowledge
What guidance could you give a patient with AIDS
or hepatitis who requests more information about
the disease?
ANSWER: Suggest that the patient contact government
agencies such as the CDC or the Consumer Information
Center by mail or on the Internet. In addition, there may be
local support groups and resource organizations available in
your area.
Impressive!
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-58
Special Issues with Terminal Illness
• Terminal – fatal
• Reactions will vary
• Help by
– Supporting and accepting patient regardless
of reaction
– Encouraging patient to express feelings
– Communicating respect through nonverbal
communication
– Meeting reasonable needs and demands
– Providing referrals to hospices
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-59
Apply Your Knowledge
Mr. Andrews recently learned his HIV status has progressed to
AIDS. When he comes into the office for an appointment, his
mood swings from anger to crying. What should you do to help
him?
ANSWER: You should show support and acceptance of Mr.
Andrews regardless of his reactions, encourage him to express
feelings, and show respect for him. If his demands are
reasonable, attempt to meet them. At this time, you should not
refer him to a hospice because there may still be treatment
options available.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-60
In Summary
3.1
Blood-borne pathogens can be transmitted by
exposure to blood and body fluids, including blood
products, human tissue, semen, vaginal secretions,
saliva from dental procedures, cerebrospinal fluid,
synovial fluid, pleural fluid, peritoneal fluid, pericardial
fluid, and amniotic fluid.
3.2
Strict adherence to Universal Precautions by treating
all individuals as if they are potentially infected with
blood-borne pathogens is essential in preventing the
spread of infection. Protecting oneself from exposure
through the use of appropriate personal protective
equipment is the best way to prevent the spread of
infection.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-61
In Summary (cont.)
3.3
The general symptoms of hepatitis include jaundice,
diminished appetite, fatigue, nausea, vomiting, joint
pain or tenderness, stomach pain, and general
malaise. The initial symptoms of AIDS are usually
severe flu-like symptoms followed later by systemic
(weight loss, fatigue, night sweats), respiratory, oral,
gastrointestinal, nervous system, and skin complaints.
3.4
The tests used to diagnose HIV infection include the
Rapid test, enzyme-linked immunosorbent assay
(ELISA) test, Western blot, and immunofluorescent
antibody (IFA) test.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-62
In Summary (cont.)
3.5
AIDS/HIV patients develop chronic disorders
including Pneumocystis carinii pneumonia (PCP),
Kaposi’s sarcoma, non-Hodgkin’s lymphoma (NHL),
tuberculosis, Mycobacterium avium complex (MAC),
meningitis, oral and vaginal candidiasis, herpes
simplex, and herpes zoster.
3.6
FDA-approved pharmaceutical agents used in the
treatment of HIV/AIDS are divided into four classes;
fusion inhibitors, nonnucleoside reverse transcriptase
inhibitors (NNRTIs), nucleoside reverse transcriptase
inhibitors (NRTIs), and protease inhibitors (PIs).
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-63
In Summary (cont.)
3.7
Several other common blood-borne pathogens are of
importance especially to patients who are
immunocompromised. It is important that the medical
assistant be able to recognize the symptoms of these
infections, which include cytomegalovirus (CMV),
erythema infectiosum (fifth disease), human T-cell
lymphotrophic virus (HTLV-1), listeriosis, malaria,
syphilis, and toxoplasmosis.
3.8
The steps involved in reporting a communicable
disease include obtaining the correct form, filling in
the appropriate blanks on the form, and submitting the
form to the physician prior to mailing it to the
appropriate agency.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-64
In Summary (cont.)
3.9
Medical assistants can assess patients’
understanding of their risk for infection, the measures
patients must take to eradicate an infection, the
potential dangers posed by treatments, and the
methods for controlling an infection’s spread.
3.10 Patients will have a variety of reactions to the news
that they are dying. Some become angry, some will
deny that they are dying, and some will get
depressed.
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.
3-65
End of Chapter 3
Thought is an infection.
In the case of certain
thoughts, it becomes an
epidemic.
~ Wallace Stevens
© 2011 The McGraw-Hill Companies, Inc. All rights reserved.