Download tbtutorial-2 - Tulane University

Preventing Tuberculosis in the Work
Place
A Computer-based Training Module
2012
Course Objectives
• Briefly describe the history of TB
• Discuss the transmission and pathogenesis of TB
• Explain the difference between TB infection and TB
disease
• Tuberculin Skin Testing
• Sites of TB Disease
• List risk factors for the development of TB disease
• Personal Protective Equipment (PPE); Preventing
the transmission of TB
Tulane University-Office of Environmental Health & Safety
Who Should Take the TB Tutorial?
• Any employee whose job requires contact with
hospital, clinic, or research study patients
• Anyone who works with children in Tulane Day
Care
• Anyone who works with individuals in homeless
shelters or prisons
• Anyone working with tuberculosis infected
animals or non-human primates
• Anyone working in a research laboratory where
tuberculosis research is performed
Tulane University-Office of Environmental Health & Safety
How long will the tutorial take?
It will take approximately 35 to 40 minutes to
navigate through the tutorial and take the quiz
located at the end. Once the quiz is complete, and
you have passed with at least an 80%, you will be
allowed to print out a copy of the “Certificate of
Completion” to keep with your records.
Tulane University-Office of Environmental Health & Safety
How will I receive credit for
taking the tutorial?
Before beginning this tutorial, you will enter
your Tulane username and Tulane email
password. Once provided, you will be able to take
the tutorial, and then take a quiz to demonstrate
mastery of the material covered. Your responses
will be automatically recorded in a database
accessible only to the Office of Environmental
Health and Safety.
Tulane University-Office of Environmental Health & Safety
A Brief History of Tuberculosis
Tuberculosis, also known as consumption,
white plague, and wasting disease, has affected
humans for centuries. Until the 1800’s, it was
widely considered to be a hereditary disease, and
its victims were sent to sanatoriums to undergo
special regimens designed to rid their bodies of the
deadly disease.
Tulane University-Office of Environmental Health & Safety
A Brief History of Tuberculosis
(cont.)
It was not until the year 1882 that a German
scientist, Robert Koch, discovered the bacteria
responsible for causing the disease,
Mycobacterium tuberculosis. Even though Koch
discovered M. tuberculosis, it was not until 1943
that an American scientist, Selman Waksman,
discovered Streptomycin, a drug capable of killing
TB bacteria.
Tulane University-Office of Environmental Health & Safety
A Brief History of Tuberculosis
(cont.)
Following the discovery, many people with
TB were cured, and the death rate began to drop
dramatically. During the years between 1943 and
the mid-1980’s, more drugs were discovered for
the treatment of TB. However, during the 1980’s
the number of TB cases was again on the rise due
to a number of individual factors. One of these
reasons was MDR-TB.
Tulane University-Office of Environmental Health & Safety
Multi-Drug Resistant TB
In some parts of the world, there are TB
strains which are resistant to standard medical
treatments. These strains are known as MDR-TB
(multi-drug resistant TB), and a few cases even
exist here in Louisiana. The good news is that
protection from exposure to MDR-TB is the same
as that required to protect against regular TB! We
will discuss engineering and work practice
controls later in the tutorial.
Tulane University-Office of Environmental Health & Safety
Transmission of Mycobacterium
tuberculosis
Mycobacterium tuberculosis, the bacteria
responsible for causing TB, is spread from person
to person via air.
Tulane University-Office of Environmental Health & Safety
Transmission of Mycobacterium
tuberculosis (cont.)
When an individual with infectious TB disease
coughs, sneezes, sings, or speaks, minute particles
containing M. tuberculosis may be expelled into
the air. These particles, or droplet nuclei, range in
size from 1-5 microns in diameter. Because of
their extremely small size, these droplet nuclei
may remain airborne for hours, given the proper
conditions.
Tulane University-Office of Environmental Health & Safety
Transmission of Mycobacterium
tuberculosis (cont.)
When another person inhales the previously
exhaled droplet nuclei, transmission may occur.
However, not everyone who is exposed to an
infectious TB patient will become infected with
M. tuberculosis. The probability of transmission
is dependent on three factors:
Tulane University-Office of Environmental Health & Safety
Factors determining transmission
of M. tuberculosis
• Contagiousness of the TB patient
• The environment the exposure occurred in
• Length of exposure
Tulane University-Office of Environmental Health & Safety
Pathogenesis of Mycobacterium
tuberculosis
When a person inhales air that contains
droplet nuclei, most of the larger droplets will
become lodged in the upper respiratory tract,
where infection is unlikely to develop. Should the
droplet nuclei reach the small air sacs of the lung
(alveoli) however, infection will begin.
Tulane University-Office of Environmental Health & Safety
Sites of TB Disease
Pulmonary TB- Pulmonary, or laryngeal TB
occurs in the lungs. About 85% of TB cases are
pulmonary. Most patients with pulmonary TB
have a cough and an abnormal chest x-ray, and are
considered infectious until certain criteria are met.
Tulane University-Office of Environmental Health & Safety
Sites of TB Disease (cont.)
Extrapulmonary TB: Extrapulmonary Tb
occurs in places other than the lungs, such as the
larynx or lymph nodes, brain, kidneys, bones, or
joints. It occurs more often in people with HIV.
Most types of extrapulmonary TB are not
considered infectious.
Tulane University-Office of Environmental Health & Safety
Sites of TB Disease (cont.)
Miliary TB: Miliary TB occurs when tubercle
bacilli enter the bloodstream and are carried to all
parts of the body, where they grow and cause
disease in multiple sites. This condition is rare,
but extremely serious, and gains its name from the
chest x-rays that contain what appears to be millet
seeds scattered throughout the lungs.
Tulane University-Office of Environmental Health & Safety
Risk Factors for the Development
of TB Disease
• Infection with HIV
• Injection of illicit drugs
• TB infection within the
last two years
• Chest x-rays suggestive
of previous TB
• Diabetes mellitus
• Silicosis
• Prolonged corticosteroid
therapy
• Immunosuppressive
therapy
• Certain types of cancer
• Severe kidney disease
• Certain intestinal
conditions
Tulane University-Office of Environmental Health & Safety
Preventing the Spread of TB
• In the Hospital
Patients suspected of having TB based on signs,
symptoms, and chest film should be admitted to a
special isolation room with a dedicated air filtration
system. Any employee who is required to have
contact with a TB patient, regardless of job
classification, must be trained to wear the N95 TB
respirator. We will discuss the N95 in greater
detail later.
Tulane University-Office of Environmental Health & Safety
Preventing the Spread of TB
(cont.)
• In the Outpatient Clinic
Since most outpatient clinics do not have special
isolation facilities, the risk of spreading TB is
minimized by having patients wear a mask and
isolating them from other patients. Also, patients
should be asked to cover their mouths and noses
when coughing or sneezing. Just as in the hospital
setting, any employee who is required to have contact
with a TB patient, regardless of job classification,
must be trained to wear the N95 TB respirator.
Tulane University-Office of Environmental Health & Safety
Preventing the Spread of TB
(cont.)
• In the Community
No universally effective means of preventing TB
in a community setting exists at this time, but the
spread of TB in the community can be slowed or
prevented by:
1.) Covering mouths and noses when
sneezing or coughing.
2.) Identifying individuals in the
community who have contracted TB
Tulane University-Office of Environmental Health & Safety
Engineering & Work Practice
Controls to Reduce TB
Transmission
In hospital and clinic areas, ventilation
systems which exhaust air to the outside have been
shown to reduce TB transmission. Ventilation is
effective if it has been properly installed and its
operation is monitored by trained technicians.
Tulane University-Office of Environmental Health & Safety
Engineering & Work Practice
Controls to Reduce TB
Transmission (cont.)
Special rooms for TB patients require a
minimum of 12 air changes/hour for new facilities,
as well as air filtration units. These rooms must
be kept under negative pressure.
Tulane University-Office of Environmental Health & Safety
Engineering & Work Practice
Controls to Reduce TB
Transmission (cont.)
Biological safety cabinets which filter air
through HEPA filters are used in many laboratory
situations where exposure to TB is likely. These
cabinets are certified annually by the Office of
Environmental Health & Safety to ensure their
proper operation.
Tulane University-Office of Environmental Health & Safety
Engineering & Work Practice
Controls to Reduce TB
Transmission (cont.)
Although ventilation, filtration, and negative
pressure rooms help, they do not completely
protect individuals from acquiring TB infection.
Personal Protective Equipment (PPE) must also be
worn. For a more in depth description of PPE,
view the following slides.
Tulane University-Office of Environmental Health & Safety
The Differences Between TB
Infection and TB Disease
TB infection means that there are M.
tuberculosis bacteria present in the body, but the
immune system of that body is controlling the
proliferation of the bacteria. This is accomplished
by the production of specialized cells that
surround the tubercle bacilli and then encapsulate
them in a hard shell.
Tulane University-Office of Environmental Health & Safety
The Differences Between TB
Infection and TB Disease (cont.)
TB infection is determined by the Mantaux
PPD skin test. Individuals with TB infection are
not contagious and therefore cannot spread the
disease to others. They will usually have normal
chest x-rays, sputum smears and cultures will
remain negative, they will be asymptomatic, and
are NOT contagious.
Tulane University-Office of Environmental Health & Safety
The Differences Between TB
Infection and TB Disease (cont)
When an individual has TB disease, their xrays will usually appear abnormal, and sputum
smears and cultures will return positive. In
addition, they will exhibit symptoms such as
cough, fever, and weight loss, and they ARE
contagious at this point.
Tulane University-Office of Environmental Health & Safety
TB Infection vs. TB Disease
TB Infection
TB Disease
Tubercle bacilli present in the body
tuberculin skin test reaction usually positive
Chest x-ray- Usually normal
Sputum smears and
cultures-negative
Symptoms-Asymptomatic
Infectiousness-Not
infectious
Not a case of TB
Chest x-ray- Usually
abnormal
Sputum smears and
cultures- positive
Symptoms- cough, fever,
weight loss, etc.
Infectiousness- Infectious
A case of TB
Tulane University-Office of Environmental Health & Safety
Personal Protective Equipment
(PPE) for Preventing TB
A respirator must be worn at all times by all
employees entering a TB patient’s room or other
area with high TB exposure potential in order to
prevent contact with airborne droplet nuclei
containing the TB organism. The N95 respirator
(mask) is the PPE used by employees to protect
themselves from getting TB.
Tulane University-Office of Environmental Health & Safety
Personal Protective Equipment
(PPE) for Preventing TB (cont.)
The N95 respirator is intended
to be worn by employees, not by
patients with active TB!!!
Tulane University-Office of Environmental Health & Safety
Personal Protective Equipment
(PPE) for Preventing TB (cont.)
The N95 respirator is not a standard paper
mask like those worn by surgeons in the OR.
Although paper masks and some other masks may
provide a certain level of protection, these masks
do not provide a tight enough fit to bar the
inhalation of TB droplet nuclei.
Tulane University-Office of Environmental Health & Safety
Personal Protective Equipment
(PPE) for Preventing TB (cont.)
Not only do the N95 respirators provide a
tighter fit around the mouth and nose, they are
made of a thicker material that is designed to
prevent the passage of TB droplet nuclei. Because
this type of respirator is more durable than regular
surgical masks, they may be used more than once
by an employee, provided they are kept clean and
dry, and no harm has come to the filter material.
Tulane University-Office of Environmental Health & Safety
Personal Protective Equipment
(PPE) for Preventing TB (cont.)
When not in use, the N95 respirator should be
kept in a plastic bag, and stored in a locker or coat
pocket.
Tulane University-Office of Environmental Health & Safety
Obtaining an N95 Respirator
The location of respirators will vary
depending on your position at the University. In
clinics and at the hospital, respirators will be a
stock item. At other sites, the respirators must be
ordered. Ordering information may be obtained
through the Office of Environmental Health &
Safety (504) 988-5486.
Tulane University-Office of Environmental Health & Safety
Steps to Obtaining and Using an
N95 TB Respirator
• Employees must receive a medical evaluation
• Employees must be trained and fit tested in order
to properly don the N95 (Contact Kim Chapital:
(504)988-2870)
• Employees must follow Tulane’s Respiratory
Protection Policy
Tulane University-Office of Environmental Health & Safety
Respirator Fit-Testing
To obtain a schedule of respirator fit testing,
please contact the office of Environmental Health
and Safety at (504)988-5486.
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (TST)
To definitively determine exposure to TB, a
tuberculin skin test, or Purified Protein Derivative
(PPD), is performed. The test involves injecting a
small amount of killed, purified proteins under the
skin.
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
72 hours after the injection, an exposed
individual will demonstrate a raised bump at the
site of injection. This raised area must be
measured by the nurse or physician that
administered the test. It is the size of the reaction
that will determine whether the reaction is positive
or negative.
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
It is important to note that a positive skin test
is a marker of infection with TB, but does not
necessarily imply active TB disease!!!
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
Who Needs PPD Testing?
 Health care workers in contact with patients
 Medical students
 Social workers
 Receptionists in clinics
 Respiratory therapists
 Etc.
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
How Often Must Tuberculin Skin Testing
Be Done?
 Annually for those in contact with patients
 At least annually for those whose jobs place them
at increased risk for TB, such as those working
with TB patients or in a laboratory that handles
TB.
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
What Does a Positive TST Mean?
A positive Tuberculin Skin Test (TST) means
that you have been exposed to the organism
responsible for causing TB, but does not
necessarily mean that you will develop active TB.
Most healthy people will never develop the
symptoms of active TB.
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
In fact, persons with a positive TST are not
even contagious unless they have the signs or
symptoms of active TB, so a positive TST test will
not interfere with your ability to work.
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
Does a Positive TST Require Medical
Treatment?
An employee with a positive TST may be
monitored on an annual basis for the development
of signs or symptoms of active TB. Not everyone
with a positive TST will require treatment.
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
The decision to medicate a person with a
positive TST that lacks signs or symptoms of TB
depends on such findings as:
 Radiologic findings on chest films
 Age of the individual
 Risk factors underlying the development of active
TB
Tulane University-Office of Environmental Health & Safety
Tuberculin Skin Testing (cont.)
Where Can I Get a Tuberculin Skin Test?
Contact your department head. Each department is
responsible for accepting charges associated with the
Tuberculin Skin Testing for high-risk employees for that
work area. The employee may get the skin test from any
healthcare provider with the charges being sent to the
employee’s department or the employee may file for
reimbursement.
Students may report to the Student Health Center for
their TST.
Tulane University-Office of Environmental Health & Safety
Tulane Medical Surveillance
Program
In the event of an exposure incident at Tulane, he
employee must notify the supervisor and the Employee
Report of Occupational Injury or Disease must be
completed. The employee must take the completed form
to a medical provider so the individual will receive medical
management and follow-up treatment, and will be
counseled on the benefits and risks of TB prophylaxis.
OEHS will follow-up with the employee as necessary.
Students should similarly complete the Student First
Report of Injury form and report to the Student Health
Center for medical evaluation.
Tulane University-Office of Environmental Health & Safety
Course Credit
You have completed the slide presentation.
Please click the link below to enter into the
test area to receive credit for course
completion.
https://audubon.tulane.edu/ehs/enterssn.cfm?testnum=133
Proceed to Quiz
Tulane University-Office of Environmental Health & Safety