Last Update: April 4, 2004 Division of Tuberculosis Control Virginia Department of Health Richmond, Virginia Tuberculosis Infection & Disease: Fundamentals for Legislators
Mar 27, 2015
Last Update: April 4, 2004
Division of Tuberculosis Control
Virginia Department of Health
Richmond, Virginia
Tuberculosis Infection & Disease: Fundamentals for Legislators
Last Update: May 28, 2004
Tuberculosis (TB): A Disease ofPublic Health Significance
Potentially fatal disease transmitted by close contactLong, multidrug treatment regimens increase potential risk of nonadherenceSerious impact on community if TB treatment is improper and/or inadequateDisproportionate impact on persons with inadequate access to health care
Last Update: May 28, 2004
Current TB Challenges in Virginia
Increasing proportion of TB patients born outside the US 48 different countries of origin in 2003 At least 20 primary languages, other than English,
spoken in 2003
High incidence of drug-resistant TB cases
21 deaths from TB in 2003 TB is a curable disease
Last Update: May 28, 2004
The Public Health Department’s Role
Recognized expert in TB control for the local communityResource for the latest on testing and treatment standardsHas access to medical experts at CDC for consultation on complicated TB casesProvides follow-up care to persons diagnosed with TBHas ultimate responsibility for TB control in VirginiaHas authority to legally enforce the VA Health Code Requires compliance to TB treatment,
www.vdh.state.va.us/epi/tb/guidebook.htm Assists in interjurisdictional referrals for patients who move residences
Last Update: May 28, 2004
VA Division of TB Control (DTC)Role of the Central Office in Richmond
Mission of the DTC Provide leadership in overcoming barriers
to protect the people of Virginia from tuberculosis
Objectives of the DTC Detect all cases of TB disease Treat all cases of active TB disease Complete treatment of all cases of active
TB disease and their infected contacts
Last Update: May 28, 2004
Virginia TB Control Laws: Key Points
Require reporting of TB disease
Require treatment and adherence to TB treatment
Allow isolation of infectious TB disease patients who refuse treatment and/or put the public at risk for TB infection
Last Update: May 28, 2004
How TB is Transmitted
TB is caused by Mycobacterium tuberculosis (tubercle bacillus)
When a person with active, infectious TB disease coughs, sneezes, laughs, sings, etc., s/he expels the TB bacteria into the air TB spreads when another person breathes in
the air that contains the TB bacteria Prolonged contact with an infectious TB
disease patient is needed for TB transmission to occur
Last Update: May 28, 2004
Factors That Determine theTransmission of TB
Infectiousness of the person with TB disease The more infectious a person, the more likely the
TB will be transmitted to others who are in close contact with this individual
Environment in which exposure to TB occurs Room size and ventilation -- Transmission of TB is
likely to occur in rooms that are small and with poor ventilation
Continues on the next slide…
Last Update: May 28, 2004
Factors That Determine theTransmission of TB (2)
Length of time spent with the infectious TB patient The longer the time spent with an infectious TB
patient, the more likely TB transmission will occur
Virulence (strength) of the TB bacteria The stronger the TB bacteria, the more likely the
transmission of TB infection will occur
Last Update: May 28, 2004
Pathogenesis of TB
TB occurs most commonly in lungs (85% of the time), but can occur in other parts of the body TB in the lungs = pulmonary TB TB outside the lungs = extrapulmonary TB
A person with TB infection and a normal immune system has a 10% chance of developing active TB disease in his/her lifetime This risk is greatest within the first 2 years after
acquiring TB infection
Last Update: May 28, 2004
TB Infection - Latent TB Infection (LTBI)
Occurs when TB bacteria are in the body, but are inactive
Does not result in any clinical symptoms of active TB disease
Is not infectious to others
Produces a “positive” reaction to the TB Skin test
Presents a normal chest X-ray
Last Update: May 28, 2004
Active TB Disease
Occurs when the inactive TB bacteria in the body (LTBI) become active
May be infectious
Has clinical symptoms (see next slide)
Last Update: May 28, 2004
Symptoms of Active TB Disease
Prolonged cough(may produce sputum)*Chest pain*Hemoptysis*FeverChills
*Symptoms commonly seen in cases of pulmonary (lung) TB
Night sweatsFatigueLoss of appetiteWeight loss orfailure to gain weight
Last Update: May 28, 2004
Persons at Higher Risk forBecoming Infected with TB
Close contacts of persons known or suspected to have active, infectious TB disease
Foreign-born persons from areas in the world where TB is common
Residents and employees of high-risk congregate settings
Health care workers (HCWs) who serve high-risk clients
Medically underserved, low-income populations
High-risk racial or ethnic minority populations
Children exposed to adults in high-risk categories
Persons who inject illicit drugs
Last Update: May 28, 2004
If Infected with TB, Factors That Could Increase the Risk for Developing TB Disease
These high-risk persons should be tested for TB infection, and if positive, treated.
HIV infection
Substance abuse
Recent TB infection
Low body weight (10% or more below the ideal)
Diabetes mellitus
Silicosis
Prolonged corticosteroid therapy
Other immunosuppressive therapy
End-stage renal disease
Cancer of the head or neck
Last Update: May 28, 2004
TB and HIV Coinfection: A Concern
For persons infected with TB, HIV positive status is the strongest risk factor for developing active TB disease
In persons who are HIV positive and have TB infection, the chances of developing TB disease increases from 10% in a lifetime to 7% to 10% each year!
Last Update: May 28, 2004
Role of Epidemiology in TB Control
Epidemiology is the study of the distribution and determinants of disease in human populations
Epidemiological data tell us: who in the population is most at risk for
developing TB disease what risk factors these individuals possess where TB disease is most prevalent how to best protect the public from the spread
of TB disease
Last Update: May 28, 2004
TB Cases Reported in Virginia, 1992-2003
See Notes pages for an explanation of this graph. [In the menu bar, click “View,” then “Notes Pages.”]
332 in 2003
Last Update: May 28, 2004
Percent of TB Cases by Age and SexVirginia, 2003 Click on “View” and “Notes Pages” to read the
explanation of the graph.
0
10
20
30
40
50
60
70
Num
ber
of C
ases
0-14 15-24 25-44 45-64 65+
Age Group in Years
Male
Female
Last Update: May 28, 2004
Percent of TB Cases in Virginia, by Region2002 and 2003
Southwest8%
Northwest5%
Central14%
Eastern17%
Northern56%
Central20%
Eastern18%
Northern46%
Northwest9%
Southwest7%
2002 2003
Last Update: May 28, 2004
Goal of Screening for LTBI
Find persons with LTBI who would benefit from treatment to prevent the development of TB disease
Find persons with TB disease who would benefit from treatment
[Persons at no risk for TB infection should not be tested for TB]
Last Update: May 28, 2004
Mantoux Tuberculin Skin Test (TST)
A test for TB infection only Preferred test for TB infection
Clinician performs procedure An injection
TB skin test result (positive, negative) based on: Size of the induration (swelling) and, Person’s risk factors for TB
Last Update: May 28, 2004
Basic Principles of TB Treatment
Goals of treatment for TB disease are: Provide the safest, most effective therapy
in the shortest possible time Give multiple drugs to which the TB
bacteria are susceptible Ensure patient adherence to therapy
Last Update: May 28, 2004
Treatment of LTBI
Treating LTBI prevents the development of TB disease, especially for persons at high risk for developing TB disease if infected with TB
Usual medication regimen for treating TB infection Isoniazid (INH) for 9 months is optimal
6 months of INH is acceptable Rifampin for 4 months is alternative in certain
circumstances
Last Update: May 28, 2004
Treatment of TB Disease
Usual medication regimen Minimum of 6 months of therapy, sometimes
longer Initial 4 drug therapy standard, and they are:
Isoniazid (INH) Rifampin Pyrazinamide (PZA) Ethambutol
Medications may need to be changed if the TB is drug resistant to any medication listed above
Last Update: May 28, 2004
Causes of Drug Resistance
Physician prescribes an inappropriate drug regimen
Patients do not take their TB medications exactly as instructed
If you become infected with TB that is already drug-resistant
Last Update: May 28, 2004
Directly Observed Therapy (DOT)
What is DOT? DOT is when a health care worker watches
a TB patient swallow each dose of the prescribed drugs
DOT is recommended for all persons who have TB disease Health care worker will conduct DOT at a
time and place convenient for the patient
Last Update: May 28, 2004
Benefits of DOT
DOT prevents drug resistance by eliminating opportunities for non-adherence to TB therapy among patients with TB disease
DOT allows for the rapid identification of problems patients may experience with their TB medications Allows early interventions to assure accurate and
correct TB therapy and patient adherence to TB therapy
Last Update: May 28, 2004
For More Information…
Division of TB ControlVirginia Department of HealthMadison Building, First Floor109 Governor StreetRichmond, VA 23219804-864-7906 (Telephone)804-371-0248 (Fax)http://www.vdh.virginia.gov/epi/tb
Centers for Disease Control and Prevention Division of TB Eliminationhttp://www.cdc.gov/nchstp/tb/default.htm