Transcript Blood-borne Pathogens, Tuberculosis Update, and Infection

Blood-borne Pathogens,
Tuberculosis Update,
and Infection Control
Timothy R. Cassity, Ph. D.
Microbiologist
October 9, 2007
Objectives

Not to bore you – or send you to LaLa Land
Objectives
Not to bore you – avoid La-La Land
 Fulfill OSHA requirements

Objectives
Not to bore you – avoid La-La Land
 Fulfill OSHA requirements
 Earn some CEUs

Objectives
Not to bore you – avoid La-La Land
 Fulfill OSHA requirements
 Earn some CEUs
 Learn – or be reminded of
information that is hopefully useful

References

Most of the information for this
presentation was taken from the CDC
website at http://www.cdc.gov/ and
included references from Morbidity and
Mortality Weekly report and Emerging
Infectious Diseases
Human Immunodeficiency Virus
(HIV)
HIV - Description of the agent
HIV - Description of the agent

This is the virus
that causes AIDS
HIV - Description of the agent
This is the virus that
causes AIDS
 HIV finds and
destroys CD4 T
cells and destroys
the immune
system.

HIV - Description of the agent



This is the virus that
causes AIDS
HIV finds and destroys
CD4 T cells and destroys
the immune system.
HIV is a retrovirus.

These are RNA viruses,
that in order to replicate
must make a DNA copy of
their RNA.
HIV - Description of the agent

HIV and other retroviruses, once
inside a cell, use reverse
transcriptase to convert their RNA
into DNA, which can be incorporated
into the host cell's genes.
HIV History – Where did it come
from?
HIV - History

Scientists identified
a type of
chimpanzee in West
Africa as the source
of HIV infection in
humans.
HIV - History

AIDS was first identified in the
United States in 1981 after a number
of homosexual men were diagnosed
with Kaposi’s sarcoma.
HIV - History

Although HIV was first identified in
1983, studies of previously stored
blood samples indicate that the virus
entered the U.S. population
sometime in the late 1970s
HIV - History

During the early 1980s, as many as
150,000 people became infected with
HIV each year.
HIV - History

By the early 1990s, this rate had
dropped to about 40,000 each year.
HIV - History

AIDS cases began to fall dramatically
in 1996, when new drugs became
available.
HIV - History

CDC estimates that about 1 million
people in the United States are living
with HIV or AIDS
HIV - History

CDC estimates that about 1 million people
in the United States are living with HIV or
AIDS
 About
one quarter of these people do
not know that they are infected
Easy questions?
HIV – Scope of Infection

Worldwide, an estimated 38 million
people were living with HIV/AIDS as
of December 2003.
HIV – Scope of Infection

Through 2003, cumulative AIDSassociated deaths worldwide
numbered more than 20 million.
HIV – Scope of Infection

Globally, approximately 5 million
new HIV infections and
approximately 3 million AIDS-related
deaths, including an estimated
490,000 children under 15 years old,
occurred in the year 2003 alone.
HIV - Pathogenesis

Untreated HIV disease is
characterized by a gradual
deterioration of immune function.
HIV - Pathogenesis
Untreated HIV disease is characterized by
a gradual deterioration of immune
function.
 Most scientists think that HIV causes
AIDS by directly inducing the death
of CD4+ T cells or interfering with
their normal function

HIV - Pathogenesis

Infection typically begins when an
HIV particle, which contains two
copies of the HIV RNA, encounters a
CD4+ cell with appropriate
receptors.
HIV - Pathogenesis

The envelope of the virus and the cell
membrane then fuse, leading to
entry of the virus into the cell.
HIV - Pathogenesis

Cell-to-cell spread of HIV also can
occur through the CD4-mediated
fusion of an infected cell with an
uninfected cell.
HIV - Pathogenesis

Once it enters the body, HIV infects a
large number of CD4+ cells and
replicates rapidly.
HIV - Pathogenesis

Once it enters the body, HIV infects a
large number of CD4+ cells and replicates
rapidly.
 During
this acute or primary phase of
infection, the blood contains many viral
particles that spread throughout the
body, seeding various organs,
particularly the lymph system.
HIV - Pathogenesis
HIV - Pathogenesis

Two to 4 weeks after exposure to the
virus, up to 70 percent of HIVinfected people suffer flu-like
symptoms related to the acute
infection.
HIV - Pathogenesis

Their immune system fights back
with killer T cells (CD8+ T cells) and
B-cell-produced antibodies.
HIV - Pathogenesis
Their immune system fights back with
killer T cells (CD8+ T cells) and B-cellproduced antibodies.
 These dramatically reduce HIV levels.

HIV - Pathogenesis

Some HIV invariably escapes the CD8
cells and antibodies and persists.
HIV - Pathogenesis
Some HIV invariably escapes the CD8 cells
and antibodies and persists.
 This is due in large part to the high
rate of mutations that occur during
the process of HIV replication.

HIV - Pathogenesis
Some HIV invariably escapes the CD8 cells
and antibodies and persists.
 The virus may hide within the
chromosomes of an infected cell and
be shielded from surveillance by the
immune system.

HIV - Pathogenesis

The median time from infection with
HIV to the development of AIDSrelated symptoms has been
approximately 10 years in the
absence of antiretroviral therapy.
HIV - Pathogenesis

Numerous studies show that people
with high levels of HIV in their
bloodstream are more likely to
develop AIDS-related symptoms or
die than those with lower levels of
virus.
Preguntas?
HIV - Transmission

HIV is a fragile virus.
 It
cannot live for very long outside the body.
HIV - Transmission

HIV is a fragile virus.
 Drying
of HIV-infected human blood or other
body fluids reduces the theoretical risk of
environmental transmission to essentially
zero.
HIV - Transmission

You cannot get HIV by:
 Shaking
hands
HIV - Transmission

You cannot get HIV by:
 Shaking
 Hugging
hands
HIV - Transmission

You cannot get HIV by:
 Shaking
hands
 Hugging
 Casual
kissing (more later)
HIV - Transmission

You cannot get HIV from:
 Toilet
seats, doorknobs, or drinking fountains
HIV - Transmission

You cannot get HIV from:
 Toilet
seats, doorknobs, or drinking fountains
 Dishes, glasses, or food
HIV - Transmission

You cannot get HIV from:
 Toilet
seats, doorknobs, or drinking fountains
 Dishes, glasses, or food
 Pets or mosquitoes
HIV - Transmission

There is no known risk of HIV
transmission to co-workers, clients,
or consumers from food-service
establishments
HIV - Transmission

HIV has NOT been recovered from
the sweat of HIV-infected persons.
HIV - Transmission
HIV has NOT been recovered from the
sweat of HIV-infected persons.
 Contact with saliva, tears, or sweat
has never been shown to result in
transmission of HIV.

HIV - Transmission

Kissing
 Casual
contact through closed-mouth kissing
is not a risk for transmission of HIV.
HIV - Transmission

Kissing
 Because
of the potential for contact with
blood during "French" or open-mouth kissing,
CDC recommends against engaging in this
activity with a person known to be infected
with HIV.
HIV - Transmission

Kissing
 However,
the risk of acquiring HIV during
open-mouth kissing is believed to be very low.
HIV - Transmission

Biting
 There
have been other reports in the medical
literature in which HIV appeared to have been
transmitted by a bite.
HIV - Transmission

Biting
 There
have been other reports in the medical
literature in which HIV appeared to have been
transmitted by a bite.
 Severe
trauma with extensive tissue tearing and
damage and presence of blood were reported in
each of these instances.
HIV - Transmission

Biting
 There
are numerous reports of bites that did
NOT result in HIV infection.
HIV - Transmission

HIV is primarily found in the blood,
semen, or vaginal fluid of an infected
person.
HIV - Transmission

HIV is transmitted in 3 main ways:
 Having
sex (anal, vaginal, or oral) with
someone infected with HIV.
HIV - Transmission

HIV is transmitted in 3 main ways:
 Having
sex (anal, vaginal, or oral) with
someone infected with HIV.
 Sharing needles and syringes with someone
infected with HIV.
HIV - Transmission

HIV is transmitted in 3 main ways:
 Having
sex (anal, vaginal, or oral) with
someone infected with HIV.
 Sharing needles and syringes with someone
infected with HIV.
 Being exposed (fetus or infant) to HIV before
or during birth or through breast feeding
HIV – Transmission in Health Care

Blood is the primary body fluid of
concern.
HIV – Transmission in Health Care

Cerebrospinal fluid, synovial fluid,
pleural fluid, peritoneal fluid,
pericardial fluid, and amniotic fluid
are also considered potentially
infectious.
HIV – Transmission in Health Care

Feces, nasal secretions, saliva,
sputum, sweat, tears, urine, and
vomitus are not considered
potentially infectious unless they are
visibly bloody
HIV - Transmission

Health-care exposures occur through:
 Needlesticks
HIV - Transmission

Health-care exposures occur through:
 Needlesticks
 Cuts
from other sharp instruments
contaminated with an infected patient's blood
HIV - Transmission

Health-care exposures occur through:
 Needlesticks
 Cuts
from other sharp instruments
contaminated with an infected patient's blood
 Contact of the eye, nose, mouth, or skin with
a patient's blood.
HIV - Transmission

Most exposures do not result in
infection.
HIV - Transmission

Transmission of HIV to patients while
in healthcare settings is rare.
HIV - Transmission

The average risk for HIV
transmission after a percutaneous
exposure to HIV-infected blood has
been estimated to be approximately
0.3%.
HIV - Transmission
The average risk for HIV transmission
after a percutaneous exposure to HIVinfected blood has been estimated to be
approximately 0.3%.
 The average risk for HIV
transmission after a mucous
membrane exposure, approximately
0.09%.

HIV - Transmission

Increased risk for HIV infection was
associated with exposure to a larger
quantity of blood from the source
person.
HIV - Transmission

The risk also was increased for
exposure to blood from source
persons with terminal illness,
possibly reflecting either the higher
titer of HIV in blood late in the
course of acquired immunodeficiency
syndrome (AIDS).
Television Timeout?
Diagnostic Testing and HIV
HIV – Principles of Diagnosis

You cannot rely on symptoms alone
because many people who are
infected with HIV do not have
symptoms for many years.
HIV – Principles of Diagnosis

The only way to know whether you
are infected is to be tested for HIV.
HIV – Principles of Diagnosis

The only way to know whether you
are infected is to be tested for HIV.
 Once
HIV enters the body, the body starts to
produce antibodies
HIV – Diagnosis

Start with a screen
 HIV
1/2 combined assay
 Sensitive but not very specific.
HIV – Diagnosis

If screen is positive, a confirmatory
test must be performed
 Western
blot
 Indirect immunofluorescence
 Immunblot
HIV – Diagnosis

HIV nucleic acid (RNA) detection
 Reverse
transcriptase DNA polymerase chain
reaction [RT-PCR]
 Primary use is not diagnostic, but to monitor
HIV load in a known positive patient.
 Useful for determining treatment regimen and
clinical course.
HIV - Prevention
A=Abstinence
HIV - Prevention

A=Abstinence
B=Be
Faithful
HIV - Prevention
A=Abstinence
 B=Be Faithful

C=Condoms
HIV - Prevention

Instruments that are intended to
penetrate the skin (such as tattooing
and acupuncture needles, ear
piercing devices) should be used
once and disposed of or thoroughly
cleaned and sterilized.
HIV - Prevention

Instruments that are intended to
penetrate the skin (such as tattooing and
acupuncture needles, ear piercing devices)
should be used once and disposed of or
thoroughly cleaned and sterilized.
 CDC
knows of no instances of HIV
transmission through tattooing or body
piercing, although hepatitis B virus has been
transmitted during some of these practices.
HIV - Prevention

Instruments not intended to
penetrate the skin but which may
become contaminated with blood (for
example, razors) should be used for
only one client and disposed of or
thoroughly cleaned and disinfected
after each use.
HIV - Vaccine

Many have been devised and tested.
HIV - Vaccine
Many have been devised and tested.
 It is difficult to prepare a vaccine and
test it adequately on human subjects.

HIV - Vaccine
Many have been devised and tested.
 It is difficult to prepare a vaccine and test
it adequately on human subjects.
 None have been effective to date.

HIV - Vaccine
Many have been devised and tested.
 It is difficult to prepare a vaccine and test
it adequately on human subjects.
 None have been effective to date.
 There are no promising prospects for
a vaccine on the horizon.

Post-Exposure Testing

Test source if possible
 If
source is negative, PEP not a big issue
Post-Exposure Testing
HIV testing should be performed on
the employee immediately after
exposure.
Post-Exposure Testing

HIV testing should be performed on
the employee immediately after
exposure.
 If
baseline test is negative, test again at 3
months.
Post-Exposure Testing
HIV testing should be performed on the
employee immediately after exposure.
 If
3 month test is negative, test again at 6
months.
Post-Exposure Testing

HIV testing should be performed on
the employee immediately after
exposure.
 If
6 month test is negative, test again at 1
year.
HIV – Post-Exposure Prophylaxis
(PEP)

If PEP is going to be administered, it
should be initiated as soon as
possible, preferably within hours of
exposure.
HIV – Post-Exposure Prophylaxis
(PEP)

Persons receiving PEP should
complete a full 4-week regimen.
HIV – Post-Exposure Prophylaxis
(PEP)

Side effects have been reported
frequently by persons taking
antiretroviral agents as PEP.
HIV – Post-Exposure Prophylaxis
(PEP)


Because of the complexity of selection of
HIV PEP regimens, consultation with
persons having expertise in antiretroviral
therapy and HIV transmission is strongly
recommended.
PEPline at
http://www.ucsf.edu/hivcntr/Hotlines/PEPli
ne; telephone 888-448-4911.
HIV – Post-Exposure Prophylaxis
(PEP)

If PEP is offered and taken and the
source is later determined to be HIVnegative, PEP should be
discontinued.
HIV – Post-Exposure Prophylaxis
(PEP)

Health care workers with
occupational exposure to HIV should
receive follow-up counseling, postexposure testing, and medical
evaluation regardless of whether
they receive PEP.
HIV – Post-Exposure Prophylaxis
(PEP)

If PEP is used, the HCW should be
monitored for drug toxicity by testing
at baseline and again 2 weeks after
starting PEP.
HIV – Post-Exposure Prophylaxis
(PEP)

If PEP is used, the HCW should be
monitored for drug toxicity by testing
at baseline and again 2 weeks after
starting PEP.
 Minimally,
laboratory monitoring for toxicity
should include a CBC and renal and hepatic
function tests.
HIV - Treatment

Potent combinations of three or more antiHIV drugs known as highly active
antiretroviral therapy, or HAART, can
reduce a person's viral load to very low
levels and in many cases delay the
progression of HIV disease for prolonged
periods.
HIV - Treatment

Before the introduction of HAART
therapy, 85 percent of patients
survived an average of 3 years
following AIDS diagnosis.
HIV - Treatment

Antiretroviral regimens have delayed
the clinical onset of AIDS and
prolonged the lives of individuals
that have AIDS.
HIV - Treatment

Antiretroviral regimens, however,
have yet to completely and
permanently suppress the virus in
HIV-infected people.
Laws and Ethics
HIV – Legal Issues

Source: Adapted from the American Bar Association’s
“Model HIV/AIDS Confidentiality Policy.”

Confidentiality must be strictly
maintained – this means anything
that could associate a person with
HIV or AIDS or any other related
disease must be kept confidential.
HIV – Legal Issues



Source: Adapted from the American Bar Association’s
“Model HIV/AIDS Confidentiality Policy.”
Confidentiality must be strictly maintained – this means
anything that could associate a person with HIV or AIDS
or any other related disease must be kept confidnetial.
This may require the use of aliases
anonymous testing.
HIV – Legal Issues




Source: Adapted from the American Bar Association’s
“Model HIV/AIDS Confidentiality Policy.”
Confidentiality must be strictly maintained – this means
anything that could associate a person with HIV or AIDS
or any other related disease must be kept confidnetial.
This may require the use of aliases anonymous testing.
Records must be stored securely – both paper and
electronic
HIV – Legal Issues

For research – aggregate, not
individual data, must be used.
HIV – Legal Issues

Because it can be easy to
inadvertently identify people when
small numbers of cases are broken
down by age, race/ethnicity, gender,
or other factors, most state
HIV/AIDS surveillance programs
have a restriction policy on small
sample size.
Hepatitis B Virus
Hepatitis B - Description of the agent

Hepatitis B virus (HBV),
can cause lifelong
infection, cirrhosis
(scarring) of the liver,
liver cancer, liver failure,
and death.
Hepatitis B - Description of the agent

Humans are the only
known host for HBV.
Hepatitis B - Description of the agent

Virions consist of an outer lipid envelope
and an icasohedral nucleocapsid core
composed of protein.
Hepatitis B - Description of the agent

The nucleocapsid encloses the viral DNA
and a DNA polymerase that has reverse
transcriptase activity.
Hepatitis B - Description of the agent

The outer envelope
contains embedded
proteins which are
involved in viral binding.
Hepatitis B - Description of the agent

HBV is relatively resilient
and, in some instances,
has been shown to remain
infectious on
environmental surfaces for
more than 7 days at room
temperature.
Hepatitis B - History

Originally called serum hepatitis.
Hepatitis B - History

The first recorded cases hepatitis B
are thought to be those that followed
the administration of smallpox
vaccine containing human lymph to
shipyard workers in Germany in l883.
Hepatitis B - History

The role of blood as a vehicle for
virus transmission was further
emphasized in 1943.
Hepatitis B - History

Australia antigen, later called
hepatitis B surface antigen (HBsAg),
was first described in 1965, and the
Dane particle (complete hepatitis B
virion) was identified in 1970.
Hepatitis B - Prevalence

In 1987, the CDC estimated the total
number of HBV infections in the
United States to be 300,000 per year,
with approximately 75,000 (25%) of
infected persons developing acute
hepatitis.
Hepatitis B - Prevalence

Of these infected individuals, 18,00030,000 (6%-10%) will become HBV
carriers, at risk of developing chronic
liver disease (chronic active
hepatitis, cirrhosis, and primary liver
cancer), and infectious to others.
Hepatitis B - Prevalence

Before use of the HBV vaccine –
 Approximately
12,000 health-care workers
became infected with HBV each year.
Hepatitis B - Prevalence

Before use of the HBV vaccine –

Approximately 12,000 health-care workers became infected with
HBV each year.
 500-600
of HBV.
of them are hospitalized as a result
Hepatitis B - Prevalence

Before use of the HBV vaccine –


Approximately 12,000 health-care workers became infected with
HBV each year.
500-600 of them are hospitalized as a result of HBV.
 700-1,200
carriers.
of those infected become HBV
Hepatitis B - Prevalence

Before use of the HBV vaccine –

Approximately 12,000 health-care workers became infected with
HBV each year.
500-600 of them are hospitalized as a result of HBV.

700-1,200 of those infected become HBV carriers.

 Of
the infected workers, approximately 250
will die (12-15 from fulminate hepatitis, 170200 from cirrhosis, and 40-50 from liver
cancer).
Hepatitis B - Prevalence

The annual number of occupational
infections has decreased 95% since
hepatitis B vaccine became available
in 1982, from >10,000 in 1983 to
<400 in 2001.
Hepatitis B- Transmission

Hepatitis B is not spread through:
 Food
or water
 Sharing eating utensils
 Breastfeeding
 Hugging or kissing
 Coughing or sneezing
 Casual contact.
Hepatitis B- Transmission

HBV is spread through
 Having sex with an infected person
without using a condom.
Hepatitis B- Transmission

HBV is spread through:
 Having sex with an infected person
without using a condom.
 The
efficacy of latex condoms in preventing
infection with HBV is unknown, but their proper
use should reduce transmission.
Hepatitis B- Transmission

HBV is spread through:

Having sex with an infected person without using a condom.
 Sharing
drugs, needles, or drug
paraphenalia.
Hepatitis B- Transmission

HBV is spread through:


Having sex with an infected person without using a condom.
Sharing drugs, needles, or drug paraphenalia.
 Needlesticks
job.
or sharps exposures on the
Hepatitis B- Transmission

HBV is spread through



Having sex with an infected person without using a condom.
Sharing drugs, needles, or drug paraphenalia.
Needlesticks or sharps exposures on the job.
 HBV
is spread from an infected mother
to her baby during birth.
Hepatitis B- Transmission

For a susceptible person, the risk
from a single needlestick or cut
exposure to HBV-infected blood
ranges from 6-30%.
Hepatitis B- Transmission

Healthcare personnel who have
received hepatitis B vaccine and
developed immunity to the virus are
at virtually no risk for infection.
Hepatitis B- Transmission

Saliva of some persons infected with
HBV has been shown to contain HBVDNA at concentrations 1/1,000 to
1/10,000 of that found in the
infected person's serum, but the
potential for salivary transmission of
HBV is remote.
Hepatitis B - Diagnosis

Frequently a person with HBV
infection has no symptoms at all or
doesn’t recall any
 Only
a blood test can tell for sure.
Hepatitis B - Diagnosis

HBsAg will be detected in an infected
person’s blood on the average of 4
weeks (range 1-9 weeks) after
exposure to the virus.
Hepatitis B - Diagnosis

If symptoms occur, they occur on the
average of 12 weeks (range 9-21
weeks) after exposure to hepatitis B
virus.
 Symptoms
occur in about 70% of patients,
even though they may be mild and many HBV
positive patients don’t recall any.
Hepatitis B - Diagnosis

If you have symptoms, they might
include:
 Jaundice
 Fatigue
 Loss
of appetite
 Nausea
 Abdominal discomfort
 Joint pain
Hepatitis B - Diagnosis
Hepatitis B - Diagnosis
Interpretation of the Hepatitis B Panel
Tests
Results
Interpretation
HBsAg
anti-HBc
anti-HBs
negative
negative
negative
Susceptible
HBsAg
anti-HBc
anti-HBs
negative
positive
positive
Immune due to natural infection
HBsAg
anti-HBc
anti-HBs
negative
negative
positive
Immune due to hepatitis B vaccination
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs
positive
positive
positive
negative
Acutely
infected
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs
positive
positive
negative
negative
Chronically
infected
HBsAg
anti-HBc
anti-HBs
negative
positive
negative
Recovering from acute HBV infection?
Slightly immune - test not sensitive enough to detect anti-HBs
Susceptible with a false positive anti-HBc
Undetectable level of HBsAg present and the person is actually
chronically infected
Hepatitis B - Diagnosis

Hepatitis B e Antigen (HBeAg):
A
secreted product of the nucleocapsid gene
of HBV and is found in serum during acute
and chronic hepatitis B. Its presence indicates
that the virus is replicating and the infected
individual has high levels of HBV.
Hepatitis B - Diagnosis

Hepatitis B e Antibody (HBeAb or
anti-HBe):
 Produced
by the immune system.
Spontaneous conversion from e antigen to e
antibody is a predictor of long-term clearance
of HBV in patients undergoing antiviral
therapy and indicates lower levels of HBV.
Hepatitis B - Prevention
Hepatitis B - Prevention

Hands and other skin surfaces should
be washed immediately and
thoroughly if contaminated with
blood, other body fluids to which
standard precautions apply.
Hepatitis B - Prevention

Hands should always be washed after
gloves are removed, even if the
gloves appear to be intact.
Hepatitis B - Prevention

All spills of blood and bloodcontaminated fluids should be
promptly cleaned up using an EPAapproved germicide or a 1:10
solution of household bleach while
wearing gloves.
Hepatitis B - Prevention

All workers should take precautions
to prevent injuries caused by
needles, scalpel blades, and other
sharp instruments or devices during
procedures; when cleaning used
instruments; during disposal of used
needles; and when handling sharp
instruments after procedures.
Hepatitis B - Prevention

Infectious waste, in general, should
either be incinerated or should be
decontaminated before disposal in a
sanitary landfill.
Hepatitis B - Prevention

Sharp items should be placed in
puncture-proof containers and other
blood-contaminated items should be
placed in leak-proof plastic bags for
transport to an appropriate disposal
location.
Hepatitis B - Prevention

Available vaccines stimulate active
immunity against HBV infection and
provide over 90% protection against
hepatitis B for 7 or more years
following vaccination.
Hepatitis B - Prevention

In 1987, the Department of Health
and Human Services and the
Department of Labor stated that
hepatitis B vaccine should be
provided to all such workers at no
charge to the worker.
Hepatitis B - Prevention

Hepatitis B vaccines also are 70%88% effective when given within 1
week after HBV exposure.
Hepatitis B - Prevention

Combination treatment with
hepatitis B vaccine and HBIG is over
90% effective in preventing hepatitis
B following a documented exposure.
Hepatitis B - Prevention

Who should receive the vaccine?
Hepatitis B - Prevention

Who should receive the vaccine?
 All
infants, at birth
Hepatitis B - Prevention

Who should receive the vaccine?

All babies, at birth
 All
children 0-18 years of age who have not
been vaccinated
Hepatitis B - Prevention

Who should receive the vaccine?

All babies, at birth

All children 0-18 years of age who have not been vaccinated
 People
of any age whose behavior or job puts
them at high risk for HBV infection.
Hepatitis B - Prevention

Hepatitis B vaccines have been
shown to be safe when administered
to both adults and children.
Hepatitis B - Prevention

Neither pregnancy nor breastfeeding
should be considered a
contraindication to vaccination of
women.
Hepatitis B - Prevention

Persons allergic to yeast should not
be vaccinated with vaccines
containing yeast.
Hepatitis B - Prevention

Recent studies indicate that
immunologic memory remains intact
for at least 23 years and confers
protection against clinical illness and
chronic HBV infection.
Hepatitis B - Prevention

Who should get post-vaccination
testing?
Hepatitis B - Prevention

Who should get post-vaccination
testing?
 Testing
for immunity is advised only for
persons whose subsequent clinical
management depends on knowledge of their
immune status.
Hepatitis B - Prevention

Who should get post-vaccination
testing?
 When
indicated, post-vaccination testing,
using the anti-HBs test, should be performed
1 to 2 months after completion of the vaccine
series.
Hepatitis B – Post-Exposure
Management

For an exposure to a source
individual found to be positive for
HBsAg, the worker who has not
previously been given hepatitis B
vaccine should receive
 The
vaccine series.
 A single dose of hepatitis B immune globulin
(HBIG), if given within 7 days of exposure.
Hepatitis B – Post-Exposure
Management

For exposures from an HBsAgpositive source to workers who have
previously received vaccine:
 Test
for antibody to hepatitis B surface
antigen (anti-HBs)
 Given one dose of vaccine and one dose of
HBIG if the antibody level in the worker's
blood sample is inadequate.
Hepatitis B – Post-Exposure
Management

If the source individual is negative
for HBsAg and the worker has not
been vaccinated, this opportunity
should be taken to provide hepatitis
B vaccination.
Hepatitis B - Treatment

There are no medications available
for recently acquired (acute) HBV
infection.
Hepatitis B - Treatment

There are antiviral drugs available for
the treatment of chronic HBV
infection.
Hepatitis D
Hepatitis D virus requires Hepatitis B virus for
replication.
 Hepatitis D is prevented with HBV vaccine

Let’s take a short break!
Hepatitis C - Description of the agent

The infection is often asymptomatic,
but ensuing chronic hepatitis can
result later in cirrhosis and liver
cancer.
Hepatitis C - Description of the agent

The Hepatitis C virus (HCV) is a small
(50 nm in size), enveloped, singlestranded, positive sense RNA virus in
the families Flaviviridae.
Hepatitis C - Description of the agent

The Flaviviridae are a family of
viruses that are primarily spread
through arthropod vectors.
 West
Nile Encephalitis virus
 Yellow fever virus
 St. Louis Encephalitis virus
Hepatitis C - History

In the 1970’s what is now known as
hepatitis C was called non-A, non-B
hepatitis (NANBH).
Hepatitis C - History

In 1987 Michael Houghton, Qui-Lim
Choo, and George Kuo at Chiron
Corporation utilized molecular
methods to identify the unknown
organism.
Hepatitis C - History

In 1988, the virus was confirmed as a
cause of non-A non-B hepatitis by
Alter who verified its presence in a
panel of NANBH specimens.
Hepatitis C - History

April of 1989, the discovery of the
virus, re-named hepatitis C virus
(HCV), was published in two articles
in the journal Science.
Hepatitis C - Prevalence

The incidence of hepatitis C has
declined steadily since peaking in the
late 1980s.
Hepatitis C - Prevalence

Hepatitis C is the leading cause of
liver transplants in the United States.
Hepatitis C - Prevalence

Hepatitis C infects an estimated 170
million people worldwide and 4
million in the United States.
Hepatitis C - Prevalence

There are about 35,000 to 185,000
new cases a year in the United
States.
Hepatitis C - Prevalence

Co-infection with HIV is common.
 Approximately
350,000 of patients in the USA
infected with HIV are also infected with the
hepatitis C virus.
Hepatitis C - Prevalence

There are numerous cases of
Hepatitis C in southern Ohio – a
higher rate per capita than other
areas.
Hepatitis C - Diagnosis

Acute hepatitis C refers to the first 6
months after infection with HCV.
Hepatitis C - Diagnosis

Acute hepatitis C refers to the first 6 months after
infection with HCV.

Between 60% to 70% of people
infected develop no symptoms during
the acute phase.
Hepatitis C - Diagnosis


Acute hepatitis C refers to the first 6 months after
infection with HCV.
Between 60% to 70% of people infected develop no
symptoms during the acute phase.

In the patients who experience acute
phase symptoms, they are generally
mild and nonspecific, and rarely lead
to a specific diagnosis of hepatitis C.
Hepatitis C - Diagnosis

The hepatitis C virus is usually
detectable in the blood within one to
three weeks after infection.
Hepatitis C - Diagnosis

Approximately 20-30% of persons
infected with HCV clear the virus
from their bodies during the acute
phase.
Hepatitis C - Diagnosis

Many patients positive for Hepatitis C
virus should also be tested for HIV
infection.
Heptatits C – Diagnosis

The detection of anti-HCV antibodies
in plasma or serum is based on the
use of enzyme immunoassays (EIA).
 Anti-HCV
antibodies always persist for life in
patients who develop chronic infection.
Hepatitis C - Diagnosis

70-80% of patients infected with
HCV develop chronic hepatitis C,
(infection lasting more than 6
months).
Hepatitis C - Diagnosis

70-80% of patients infected with HCV develop chronic
hepatitis C, (infection lasting more than 6 months).

Liver biopsy is the best test to
determine the amount of scarring
and inflammation.
Hepatitis C - Diagnosis

Anti-HCV antibodies can be detected
in:
 80%
of patients within 15 weeks after
exposure
 >90% within 5 months after exposure
 >97% by 6 months after exposure.
Hepatitis C - Diagnosis

Anti-HCV antibodies indicate
exposure to the virus, but cannot
determine if ongoing infection is
present.
Hepatitis C - Diagnosis

Anti-HCV antibodies indicate exposure to the
virus, but cannot determine if ongoing infection
is present.

The presence of the virus is tested for
using molecular nucleic acid testing
methods (PCR, TMA, or branched
DNA (b-DNA))
Hepatitis C - Diagnosis



Anti-HCV antibodies indicate exposure to the virus, but
cannot determine if ongoing infection is present.
The presence of the virus is tested for using molecular
nucleic acid testing methods (PCR, TMA, or branched
DNA (b-DNA))
All HCV nucleic acid molecular tests have
the capacity to detect not only whether
the virus is present, but also to measure
the amount of virus present in the blood.
Hepatitis C – Chronic infection

Among untreated patients, roughly
one-third progress to liver cirrhosis
in less than 20 years.
Hepatitis C – Chronic infection

Among untreated patients, roughly one-third progress to
liver cirrhosis in less than 20 years.

Another third progress to cirrhosis
within 30 years.
Hepatitis C – Chronic infection

Among untreated patients, roughly one-third progress to
liver cirrhosis in less than 20 years.

Another third progress to cirrhosis within 30 years.

The remainder of patients appear to
progress so slowly that they are
unlikely to develop cirrhosis within
their lifetimes.
Hepatitis C - Transmission

In 2005, injection-drug use
continued to be the most commonly
identified risk factor for infection.
Hepatitis C - Transmission

Studies conducted to evaluate the
role of sexual transmission of HCV
have indicated that the virus is
spread inefficiently through this
route, although it does occur.
Hepatitis - Transmission

HCV is not spread through:
 Casual
contact
 Hugging or kissing
 Sharing eating or cooking utensils.
Hepatitis - Transmission

HCV is spread by:
illicit drug use
 Occupational expose to blood
 Body piercing and tatoos
 Mother-to-child transmission of hepatitis C
occurs relatively infrequently.
 Blood transfusions - rare today because blood
supply is tested for HCV.

Hepatitis C - Transmission
Hepatitis C - Prevention

There is no vaccination that protects
against contracting Hepatitis C.
Hepatitis C - Prevention

Avoid high risk activities and contact
with blood from infected individuals.
Hepatitis C – Post-Exposure

Determine status of source of
exposure, if negative, no additional
testing necessary
Hepatitis C – Post-Exposure

If source is positive:
 Baseline
testing at time of exposure
Hepatitis C – Post-Exposure

If source is positive:
 If
baseline is negative, test at 3 months
Hepatitis C – Post-Exposure

If source is positive:
 If
employee was negative at 3 months, test
again at 6 months.
Hepatitis C - Treatment

There is a very small chance of
clearing the virus spontaneously (0.5
to 0.74% per year).
Hepatitis C - Treatment

Current treatment is a combination
of pegylated interferon alpha (brand
names Pegasys and PEG-Intron) and
ribaviron for a period of 24 or 48
weeks, depending on genotype.
Hepatitis C - Treatment

Those with low initial viral loads
respond much better to treatment
than those with higher viral loads
(greater than 2 million virons/ml).
Hepatitis C - Treatment

The treatment may be physically
demanding, particularly those with a
prior history of drug or alcohol abuse.
 The
drop-out rate for treatment of hepatitis C
treatment is high.
Fast Break?
Infection Control
Infection Control - Standard
Precautions

General infection-control procedures
are designed to prevent transmission
of a wide range of microbiological
agents and to provide a wide margin
of safety in the varied situations
encountered in the health-care
environment.
Infection Control Policies, Procedure
and Documentation

Most important Aspect - Common
Sense
Infection Control Policies, Procedure
and Documentation

Most important Aspect - Common Sense

Standard precautions
Infection Control Policies, Procedure
and Documentation



Most important Aspect - Common Sense
Standard precautions
Specific infection control and
isolation requirements fro specific
infections
Standard Precautions

Use the appropriate barrier
Standard Precautions

Use the appropriate barrier

Use proper hand hygiene
 Alcohol
hand sanitizer
 Soap and water
Standard Precautions


Use the appropriate barrier
Use proper hand hygiene



Alcohol hand sanitizer
Soap and water
Do not eat, drink, smoke, apply
cosmetics, or handle contact lenses
in an area where there is a possibility
of exposure to an infectious agent.
Standard Precautions


Use the appropriate barrier
Use proper hand hygiene


Alcohol hand sanitizer
Soap and water

Do not eat, drink, smoke, apply cosmetics, or handle
contact lenses in an area where there is a possibility of
exposure to an infectious agent.

Careful handling of sharp objects
Disinfectants

What is the best overall disinfectant?
Disinfectants

What is the best overall disinfectant?
 Sodium
hypochlorite – a 1:10 dilution of
household bleach with 5% sodium
hypochlorite.
 Must be made fresh daily
 Dispatch – stabilized Na hypochlorite
Disinfectants

What about Sanicloths?
 Good
for electrical equipment and things that
bleach would deteriorate.
 Not as good of a disinfectant as bleach.
Gloves

Not a replacement for handwashing
Gloves

Not a replacement for handwashing

Use when exposure to blood or a
body fluid is anticipated.
Gloves



Not a replacement for handwashing
Use when exposure to blood or a body fluid is
anticipated.
Only single-use gloves should be
used in patient care.
Gloves




Not a replacement for handwashing
Use when exposure to blood or a body fluid is
anticipated.
Only single-use gloves should be used in patient care.
Gloves used in patient care (ie. single
use) should not be washed or
disinfected and re-used.
Disposal of Sharps

Most sharps injuries are avoidable!
Disposal of Sharps

Most sharps injuries are avoidable!

Most people who are injured with
sharps were not the persons using
the sharp!
Disposal of Sharps

Place sharps immediately into an
impervious sharps container.
 Do
not leave needles lying on beds or in
linens or put into regular trash
 Do not recap needles (except for some special
use needles, then there should not be picked
up to recap).
Disposal of Sharps

Place sharp object in sharp container
with needle facing down.
Disposal of Sharps

Place sharp object in sharp container with needle facing
down.

Do not overfill a sharps container.
Disposal of Sharps



Place sharp object in sharp container with needle facing
down.
Do not overfill a sharps container.
When possible, sharps containers
should no be accessible to patients
Infection Control – OSHA
Requirements

Employers should make protective
equipment available to all workers
when they are engaged in Category I
or II activities.
Infection Control – OSHA
Requirements

Employers should ensure that the
appropriate protective equipment is
used by workers when they perform
Category I activities.
Infection Control – OSHA
Requirements

Employers should establish a detailed
work practices program that includes
standard operating procedures
(SOPs) for all activities having the
potential for exposure.
Infection Control – OSHA
Requirements

Employers should monitor the
workplace to ensure that required
work practices are observed and that
protective clothing and equipment
are provided and properly used.
Infection Control – OSHA
Requirements

In addition, training records,
indicating the dates of training
sessions, the content of those
training sessions along with the
names of all persons conducting the
training, and the names of all those
receiving training should also be
maintained.
Infection Control – OSHA
Requirements

All workers whose jobs involve
participation in tasks or activities
with exposure to blood or other body
fluids to which universal precautions
apply should be vaccinated with
hepatitis B vaccine.
Tuberculosis
Tuberculosis - History

In 1900 TB was the leading cause of
death in the U.S.
Tuberculosis - History

Nationwide, from the late 40’s the
incidence decreased until 1984.
 Cases
decreased such that it was thought that
TB would be a historic disease by 2005.
Tuberculosis - History

Cases began to increase in 1985,
mainly due to HIV and MDR strains.
Tuberculosis - Prevalence

An estimated 10-15 million
Americans are infected with
Mycobacterium tuberculosis
Tuberculosis - Prevalence

About 10 percent of these infected
individuals (that do not receive
prophylaxis) will develop TB at some
point in their lives.
Tuberculosis - Prevalence

Locally, we have a low rate of
tuberculosis – 1-3 new cases per
year.
Tuberculosis – Latent vs. Active

Two forms of the
disease

Latent tuberculosis - positive
PPD only, no symptoms,
cannot spread to others
Tuberculosis – Latent vs. Active

Two forms of the
disease

Active tuberculosis –
symptoms are present – can
spread to others if pulmonary
infection.
Infection via inhalation of droplets
containing M. tuberculosis
Bacteria are engulfed by macrophages, but not killed
Initial symptoms – 1-2 weeks
following infection
Dissemination to other
organs via lymphatics
Pneumonic symptoms resolve
Cellular immunity develops - PPD turns positive
Dissemination ceases
Immunocompetent host
Most bacteria are killed by
macrophages
Latent disease – bacteria may remain
viable for years
Immunosuppressed host
Immunosuppression
ACTIVE
TUBERCULOSIS
Tuberculosis

Can be (and usually is) carried for a
long time before onset of active
disease.
Tuberculosis

Transmitted by inhaling infected
droplets from a person with active
pulmonary tuberculosis.
Tuberculosis

With active TB, respiratory isolation
and standard precautions are used to
prevent spread of infection.
Tuberculosis - Types

Causes a wide variety of infections,
such as pulmonary infections, skin
and sinus tract infections, renal
infections, osteomyelitis, nonspecific lymphatic disease.
Tuberculosis – Relationship to HIV

Because HIV infection weakens the
immune system, people infected with
HIV and TB have a 100 times greater
risk of developing active TB disease
compared to people not infected with
HIV.
Tuberculosis – Relationship to HIV

TB is the cause of death for one out
of every three people with AIDS
worldwide.
Tuberculosis – Relationship to HIV

The spread of the HIV epidemic has
significantly impacted the TB
epidemic.
Tuberculosis – Relationship to HIV

Individuals that are HIV positive may
not test correctly with PPD.
Tuberculosis – Relationship to HIV

Individuals that have HIV and active
TB have more organisms and are a
greater threat to spread the disease.
Tuberculosis – Relationship to HIV

All people infected with HIV should
be tested for TB, and, if infected,
complete preventive therapy as soon
as possible to prevent TB disease.
Tuberculosis - MDR
For active TB, treatment usually with
3-4 medications to prevent selection
of resistant TB strains.
 For latent TB, treatment for 6 months
with INH alone, if tolerated.

Questions or Comment?
References

Most of the information for this
presentation was taken from the CDC
website at http://www.cdc.gov/ and
included references from Morbidity and
Mortality Weekly report and Emerging
Infectious Diseases
Thanks to our sponsor!
Scioto County Medical Society
Thank you for your time and
attention!
It has been a pleasure to be with
you this evening!