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Transcript
Chapter 14: Infectious
Diseases, Bloodborne
Pathogens, and Universal
Precautions
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Bloodborne pathogens are transmitted
through contact with blood or other
bodily fluids
• Hepatitis, especially hepatitis B, human
immunodeficiency virus are of serious
concern
• Healthcare facility must be maintained
as clean and sterile to prevent spread of
disease and infection
• Must take precautions to minimize risk
© 2011 McGraw-Hill Higher Education. All rights reserved.
Infectious Disease
• Invasion of a host (animal or person) by
a microorganism (pathogen)
– Causes disease by disrupting vital body
processes
– Stimulate the immune system to react
defensively
• Immune response = fever, inflammation, or
other damaging symptoms
– Most common pathogens = bacteria,
viruses, parasites or fungi
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Microorganism can live in host and be
harmless until an agent and mode of
transportation allows for transfer of
microorganism  pathogen infection
• An infectious disease = contagious if
transmission occurs from one individual to
another
– Direct vs. indirect transmission
– 3 Types of direct transmission
• Contact of body surfaces (touching, sexual
intercourse)
• Droplet spread (inhalation or air droplets)
• Fecal-oral spread (feces on hands  contact
with mouth
© 2011 McGraw-Hill Higher Education. All rights reserved.
– Indirect transmission
• Travels via inanimate object
– Water, food, towels, clothing, utensils
• Via vectors
– Insects, birds, animals
• Airborne transmission
– Infected particles suspended in air – infected via
sharing air supply
• Pathogen entry into body
– Through skin, respiratory system, digestive
or reproductive system
• Ability to generate infection dependent on:
– Acquired immunity
– Overall health
– Health-related behavior
© 2011 McGraw-Hill Higher Education. All rights reserved.
Stages of Infection
• Incubation stage
– From time pathogen enters body to time signs
and symptoms of disease appear
– Lasting from few hours to months depending
on concentration, virulence, level of immune
response, presence of other health problems
• Prodromal stage
– Watery eyes, runny nose, slight fever and
malaise may develop briefly
– Host can transfer pathogen to other hosts
– Host should be isolated to prevent
transmission
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Acute stage
– Disease reaches point of greatest development
while body resists further damage from pathogen
• Decline stage
– First signs of recovery
– Could relapse if patient becomes overextended
• Recovery stage
– Overcome invading pathogen
– Patient remains susceptible
– Body may have built up immunity and will be
resistant to future exposure (may not be
permanent)
© 2011 McGraw-Hill Higher Education. All rights reserved.
The Immune System
• Mechanical defenses
– Separates the internal body from the
external environment
• Skin, mucous membranes, nasal hairs, cilia
lined airways
• Cellular System (Immune system)
– Eliminates microorganisms, foreign
proteins and antigens
– Consists of T-cells and B-cells
• Located in bloodstream lymphatic tissues and
interstitial fluid
© 2011 McGraw-Hill Higher Education. All rights reserved.
– Antigens trigger leukocytes and
macrophages to locate and destroy
antigens
• T-cells facilitate macrophages
• B-cells transformed into specialized cells
(plasma cells) capable of producing antibodies
– Antibodies neutralize antigens via lysis and
phagocytosis
– Memory T-cells are formed to record
information regarding antigens and
immune response
© 2011 McGraw-Hill Higher Education. All rights reserved.
Figure 14-1
© 2011 McGraw-Hill Higher Education. All rights reserved.
Immunity
• After effectively managing invading
antigens the system is primed for future
encounters
– Acquired immunity
• Developed artificially through
vaccination/immunizations or passively when
antibodies are injected
• Both can provide important protection against
infectious disease
© 2011 McGraw-Hill Higher Education. All rights reserved.
Immunizations
• Available and should be provided for all
• Possible vaccinations include:
– Diphtheria
– Pertussis (whooping cough)
– Hepatitis B
– Haemophilus influenza type B
– Tetanus
– Rubella (German measles) & measles
– Polio, mumps & chickenpox
• Helps to minimize incidence of childhood
communicable disease
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Immunizations have eradicated many
infectious diseases world wide
• Epidemiology is a tool used to study
infectious disease in a population
• Disease outbreaks
– Sporadic (occasional, occurrence)
– Endemic (regular cases often occurring in
a region)
– Epidemic (unusually high number of cases
in a region
– Pandemic (global epidemic)
© 2011 McGraw-Hill Higher Education. All rights reserved.
Preventing Spread of
Infectious Disease
• Must be diligent in efforts to minimize
transmission of disease
• Most effective practice = washing hands
• Ensure that patient immunizations are
up to date
• Be sure to educate patients on inability
of antibodies to impact viruses, and
need to taking antibiotics as directed
• Encourage healthy lifestyles in patients
© 2011 McGraw-Hill Higher Education. All rights reserved.
Bloodborne Pathogens
• Pathogenic organisms, present in human
blood and other fluids (cerebrospinal fluid,
semen, vaginal secretion and synovial
fluid) that can potentially cause disease
• Most significant pathogens are hepatitis B
(HBV) , hepatitis C (HBC) and human
immunodeficiency virus (HIV)
© 2011 McGraw-Hill Higher Education. All rights reserved.
Virus Reproduction
• Submicroscopic
parasitic organism is
dependent on
nutrients of cell
• Strand of DNA or
RNA dependent on
metabolic and
reproductive activity
of cell
• Redirect cell activity
to create more
viruses
Figure 14-3
© 2011 McGraw-Hill Higher Education. All rights reserved.
Hepatitis B
• Attacks liver, results in lifelong infection, cirrhosis,
liver cancer, liver failure and death
• Spread when blood from infected person enters
the body of someone who is not infected
– Unprotected sex, sharing needles
• Individuals who have been vaccinated are at
virtually no risk for infection
• 350-400 million people are infected world-wide
• 8700 healthcare workers contract HBV each year,
with 200 of these ending in death
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Signs and symptoms
– Flu-like symptoms like fatigue, weakness,
nausea, abdominal pain, headache, fever,
and possibly jaundice
– Possible that individual will not exhibit
signs and symptoms -- antigen always
present in these individuals
– Can be unknowingly transferred
– Chronic active hepatitis may occur
because of problem with immune system,
preventing complete destruction of virus
infected liver cells
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Signs & Symptoms (continued)
– May test positive for antigen w/in 2-6 weeks of
symptom development
– 85% recover within 6-8 weeks
• Prevention
– Good personal hygiene and avoiding high risk
activities
– Proceed with caution as HBV can survive in
blood and fluids, in dried blood and on
contaminated surfaces for at least 1 week
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Management
– Vaccination against HBV should be
provided by employer to those who may be
exposed
– Athletic trainers and allied health
professionals should be vaccinated
– Three dose vaccination over 6 months
– After second does 87% of those receiving
vaccine will be immune and 96% after the
third dose
– Post-exposure vaccination is also available
after coming into contact with blood or
fluids
© 2011 McGraw-Hill Higher Education. All rights reserved.
Hepatitis C
• Both an acute and chronic form of liver disease
caused by hepatitis C virus (HCV)
• Most common chronic bloodborne infection in
United States
• Leading indication for liver transplant
• Signs & Symptoms
– 80% of those infected have no S&S
– May be jaundice, have mild abdominal pain, loss of
appetite, nausea, fatigue, muscle/joint pain, and/or
dark urine
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Prevention
– Occasionally spread through sexual contact
– Spread via contact with blood of infected person,
sharing needles
• Management
– No vaccine for preventing HCV
– Multiple tests available to check for HCV
• Single positive = infection
• Single negative = does not necessarily mean no
infection
– Interferon and ribavirin are 2 drugs used in
combination and appear to be the most effective
for treatment
– Drinking alcohol can make liver disease worse
© 2011 McGraw-Hill Higher Education. All rights reserved.
Human Immunodeficiency
Virus
• A retrovirus that combines with host cell
• Infects T4 blood cells, B cells and
monocytes (macrophages)
• Estimated that 11 out of 1000 adults are
infected with HIV
• 4.1 million new HIV infections occurred
world-wide in 2005
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Symptoms and Signs
– Transmitted by infected blood or other fluids
– Fatigue, weight loss, muscle or joint pain,
painful or swollen glands, night sweats and
fever
– Antibodies can be detected in blood tests
within 1 year of exposure
– May go for 8-10 years before signs and
symptoms develop
– Most that acquire HIV will develop acquired
immunodeficiency syndrome (AIDS)
© 2011 McGraw-Hill Higher Education. All rights reserved.
Acquired Immunodeficiency
Syndrome (AIDS)
• Collection of signs and symptoms that
are recognized as the effects of an
infection
• No protection against the simplest
infection
• Positive test for HIV cannot predict
when the individual will show symptoms
of AIDS
© 2011 McGraw-Hill Higher Education. All rights reserved.
• As of 2007, 1.1 million people in the
U.S. were living with HIV infection;
468,000 were living with AIDS
• 50% develop AIDS w/in 10 years of HIV
infection
• After contracting AIDS, people
generally die w/in 2 years of symptoms
developing
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Management
– No vaccine for HIV, no cure even though
drug therapy is available
– Research looking for preventive vaccine
and effective treatment
– Most effective drug combination
• Drug which blocks enzyme action responsible
for new virus cell components
• Drug which blocks copying of viral agents,
disabling synthesis of new viruses
• Third drug helps protect T cells, slowing
progression of HIV
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Prevention
– Greatest risk is through intimate sexual
contact with infected partner
– Choose non-promiscuous sex partners and
use condoms for vaginal or anal intercourse
– Latex condom provides barrier against HBV
and HIV
– Condoms with reservoir tip reduces chance of
ejaculate being released from sides
– Water-based, greaseless spermicides or
lubricants should be avoided
– If condom breaks, vaginal spermicide should
be used immediately
– Condom should be carefully removed and
discarded
© 2011 McGraw-Hill Higher Education. All rights reserved.
Additional Hepatitis Viruses
• Hepatitis A
– Causes inflammation of liver – does not
lead to chronic liver disease
– Transmitted by fecal or oral routes through
close personal contact or contaminated
food/water
• Transmitted in milk, shellfish, salads, sliced
meat
– May show no outward signs or symptoms
– Adults may exhibit dark urine, light stools,
fatigue, jaundice and fever
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Hepatitis D (HDV) causes inflammation
of the liver
– Found often in those infected with HBV
– Transmitted through contact with infected
blood, needles or sexual contact
– Symptoms more severe than with HBV
• Hepatitis E (HEV)
– Causes inflammation of the liver
– Rarely found in the United States
– Transmitted through fecal and oral routes
from contaminated water supplies
© 2011 McGraw-Hill Higher Education. All rights reserved.
Bloodborne Pathogens in
Athletics
• Chance of transmitting HIV among
athletes is low
• Minimal risk of on-field transmission
• Some sports have potentially higher risk
for transmission because of close
contact and exposure to bodily fluids
– Martial arts, wrestling, boxing
© 2011 McGraw-Hill Higher Education. All rights reserved.
Policy Regulation
• Athletes are subject to procedures and
policies relative to transmission of
bloodborne pathogen
• A number of sport professional
organizations have established policies to
prevent transmission
• Organizations have also developed
educational programs concerning
prevention, and medical assistance
• Institutions should take responsibility to
educate student athletes
© 2011 McGraw-Hill Higher Education. All rights reserved.
• At high school level, parents should also
be educated
• Make athletes aware that greatest risk
is involved in off-field activities
• Athletic trainer should take responsibility
of educating and informing student
athletic trainers of exposure and control
policies
• Institutions should implement policies
concerning bloodborne pathogens
• Follow universal precautions mandated
by OSHA
© 2011 McGraw-Hill Higher Education. All rights reserved.
HIV and Athletic Participation
• Should HIV positive Athletes be able to
participate in sport?
- No definitive answer as to whether asymptomatic HIV carriers
should participate in sport
• Bodily fluid contact should be avoided
• Avoid exhaustive exercise that may lead
to susceptibility to infection
© 2011 McGraw-Hill Higher Education. All rights reserved.
HIV and Athletic Participation
• American with Disabilities Act says
athletes infected cannot be
discriminated against and may only be
excluded with medically sound basis
– Must be based on objective medical
evidence
– Also must take into consideration risk
to patient and other participants and
means to reduce risk
© 2011 McGraw-Hill Higher Education. All rights reserved.
Testing Athletes for HIV
• Should not be used as screening tool
• Mandatory testing may not be allowed due
to legal reasons (American with Disabilities
Act and HIPAA)
• Testing should be secondary to education
• Athletes engaged in risky behavior should
undergo voluntary anonymous testing for
HIV
• Multiple tests are available to test for
antibodies for HIV proteins
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Detectable antibodies may appear from 3
month to 1 year following exposure
• Testing should occur at 6 weeks, 3 months,
and 1 year
• Home test kits are also available which allow
you to send blood work to lab for analysis
– Home Access test is FDA approved
– Lab analyzes dried blood sample and labeled
with personal identification number (PIN)
– Acquire results and counseling confidentially
with PIN
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Many states have enacted laws that
protect confidentiality of HIV infected
person
• Athletic trainer should be familiar with state
laws and maintain confidentiality and
anonymity of testing
© 2011 McGraw-Hill Higher Education. All rights reserved.
Universal Precautions in
Athletic Environment
• In 1991 OSHA (Occupational Safety and
Health Administration) established standards
for employer to follow that govern
occupational exposure to blood-borne
pathogens
• Developed to protect healthcare provider and
patient
• All sports programs should have exposure
control plan
– Should include counseling, education,
volunteer testing, and management of bodily
fluids
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Preparing the Athlete
– Prior to participation, all open wounds and lesions
should be covered with dressing that will not allow
for transmission
– Occlusive dressing lessens chance of crosscontamination
• Hydrocolloid dressing is considered a superior
barrier
• Reduces chance that wound will reopen, as wound
stays moist and pliable
© 2011 McGraw-Hill Higher Education. All rights reserved.
• When Bleeding Occurs
– Athletes with active bleeding must be removed
from participation and returned when deemed
safe
– Bloody uniform must be removed or cleaned
to remove infectivity
• Personal Precautions
– Those in direct contact must use
appropriate equipment including
• Latex gloves, gowns, aprons, masks and
shields, eye protection, disposable
mouthpieces for resuscitation
• Emergency kits should contain, gloves,
resuscitation masks, and towelettes for
cleaning skin surfaces
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Personal Precautions (continued)
– Doubling gloving is suggested with severe
bleeding and use of sharp instruments
– Extreme care must be used with glove
removal
– Hands and skin surfaces coming into contact
with blood and fluids should be washed
immediately with soap and water (germicidal
agent)
– Hands should be washed between patients
© 2011 McGraw-Hill Higher Education. All rights reserved.
– Latex Sensitivity and Nonlatex Gloves
• Nonlatex glove use is recommended for
athletic trainers
• May cause allergic reactions if use latex
gloves
– Contact dermatitis
– Systemic reaction
• Some become more susceptible due to
repeated exposure
• Management of acute reaction includes
removing irritant, cleansing affected area,
monitoring vital signs, seeking additional
medical assistance as warranted
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Availability of Supplies and Equipment
– Must also have chlorine bleach,
antiseptics, proper receptacles for soiled
equipment and uniforms, wound care
equipment, and sharps container
– Biohazard warning labels should be affixed
to containers for regulated waste,
refrigerators containing blood and
containers used to ship potentially
infectious material
– Labels are fluorescent orange or red
– Red bags or containers should be used for
potentially infectious material
© 2011 McGraw-Hill Higher Education. All rights reserved.
Figure 14-4
Figure 14-5
© 2011 McGraw-Hill Higher Education. All rights reserved.
– Disinfectant
• Contaminated surfaces should be clean
immediately with solution of 1:10 ratio
approved disinfectant to water
• Should inactivate HIV
• Contaminated towels should be bagged,
labeled, and separated from other soiled
laundry, then transported in biohazard
container
–Wash in hot water (159.8 degrees F for
25 minutes)
–Laundry done outside institution should
be OSHA certified
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Sharps
– Needles, razorblades,
and scalpels
– Use extreme care in
handling and
disposing all sharps
– Do not recap, bend
needles or remove
from syringe
– Scissors and tweezers
should be sterilized
and disinfected
regularly
Figure 14-6
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Protecting the Athletic Trainer
– OSHA guidelines are designed to protect
coaches, athletic trainers and other employees.
– Coaches generally do not come into contact
with blood and therefore risk is greatly reduced
– Responsibility of institution to protect athletic
trainer
• Provide necessary supplies and education
– Athletic trainer has personal responsibility to
follow guidelines
• Minimize risks by not eating/drinking, applying
cosmetics/lip balm, handling contact lenses, and
touching face before washing hands
© 2011 McGraw-Hill Higher Education. All rights reserved.
• Protecting the Athlete From Exposure
– Use mouthpieces in high-risk sports
– Shower immediately after practice or
competition
– Athletes exposed to HIV or HBV should be
evaluated and immunized against HBV
© 2011 McGraw-Hill Higher Education. All rights reserved.
Post-exposure Procedures
• Athletic trainer should have confidential
medical evaluation that documents
exposure route, identification of
source/individual, blood test, counseling
and evaluation of reported illness
• Laws that pertain to reporting and
notification of results relative to
confidentiality vary from state to state
© 2011 McGraw-Hill Higher Education. All rights reserved.