Testing for Tuberculosis - Michigan · • Describe TB pathogenesis from Mycobacterium tuberculosis...
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Testing for Tuberculosis: Tuberculin Skin Test & IGRA Blood Test Updated 2/20 This continuing nursing education activity was awarded a maximum of 4.00 nursing contact hours. This continuing nursing education activity was approved by the Ohio Nurses Association, an accredited approver by the American Nurses Credentialing Center’s Commission on Accreditation. (OBN‐001‐91) 2/20 1
Transcript of Testing for Tuberculosis - Michigan · • Describe TB pathogenesis from Mycobacterium tuberculosis...
Testing for Tuberculosis:Tuberculin Skin Test &
IGRA Blood Test
Updated 2/20
This continuing nursing education activity was awarded a maximum of 4.00 nursing contact hours. This continuing nursing education activity was approved by
the Ohio Nurses Association, an accredited approver by the American Nurses Credentialing Center’s Commission on Accreditation. (OBN‐001‐91)
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Criteria for Completion: To obtain continuing education hours and TST certification the participant must:
• Be in attendance for the entire workshop
• Sign your name on the sign‐in sheet clearly showing credentials and email address
• Complete the post‐test with a passing score of 80% or greater
• Complete the practicum with a passing score of 87.5% or greater and show correct intradermal injection
Disclosure: There is no conflict of interest for anyone with the ability to control content for this activity.
Disclosures
This continuing nursing education activity was approved by the Ohio Nurses Association, an accredited approver by the American Nurses Credentialing Center’s Commission on Accreditation. (OBN‐001‐91) Activity #21884
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Learning Objectives
• Describe global, national, and state epidemiologic trends for tuberculosis (TB).
• Identify factors that contribute to Mycobacterium tuberculosis transmission.
• Describe TB pathogenesis from Mycobacterium tuberculosis infection to TB disease.
• Explain the difference between latent TB infection (LTBI) and TB disease.
• Identify methods used for evaluating LTBI and TB disease.
• List high‐risk target groups for TB testing.
• Demonstrate how to place, read, and interpret the Tuberculin Skin Test (TST).
• Describe how to interpret Interferon‐Gamma Release Assay (IGRA) test results.
• Understand the role of local health in TB control.
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Components of the Workshop
• Pre‐Test
• PowerPoint Presentation
I. History and Epidemiology of TB
II. Mycobacterium tuberculosis Transmission & Pathogenesis
III. Testing and Evaluating for TB
IV. TB Case Management
• Video: Testing for TB Infection
• Post‐Test
• Practicum: Administer and Read the TB Skin Test
• Evaluation
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I. History and Epidemiology of Tuberculosis
• Global history of TB
• Coverage of the BCG vaccine
• Epidemiology of TB: Global, United States, and Michigan
• Quiz question
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Global History of Tuberculosis
Ancient Times
//1900 1950 20001875 19751850 2025
18511 in 4 people killed by TB in Europe and US Charles Mantoux
introduces TST
19071944
Streptomycin, first anti‐TB med, discovered
Modern Age
TB of the spine found in Egyptian mummy
1000 BC 1921
First BCG vaccine administered
1925
1970
First outbreak of drug‐resistant TB in the US
FDA approves the first anti‐TB drug in more than 40 years
2012
1882
Robert Koch discovers M. tuberculosis
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Slide 6: Global History of Tuberculosis
• TB is a very old disease, dating back several thousand years. For example, Egyptian mummies from approximately 1000 BC were discovered to have M. tuberculosis in their spine.
• The “modern” era of TB control began in the mid‐1800s with the opening of sanatoriums, or dedicated TB hospitals, used to isolate TB patients from the rest of society. Sanatoriums remained a core part of the TB control strategy for the next 90 years. During this time, it is estimated that TB claimed the lives of 25% of people in Europe and US.
• Almost 30 years later, scientist Robert Koch discovered that TB disease is caused by bacteria, and he named the new species Mycobacterium tuberculosis.
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• In 1907, Charles Mantoux introduced the tuberculin skin test, a method we still use 110 years later, to test for TB infection.
• BCG, the first and only TB vaccine, was first administered in 1921. Although efficacy of the vaccine wanes over time, BCG is helpful in preventing life‐threatening TB disease in infants and children.
• Streptomycin was discovered in 1944, and by 1945 it was the first antibiotic used to treat TB. In 1952, isoniazid became the inexpensive, safe, and well‐tolerated anti‐tuberculosis medication. In the 1970’s rifampin enabled the course of treatment to be reduced to nine months, and the later incorporation of pyrazinamide and ethambutol further reduced treatment duration to six months.
• 1970 saw the first US outbreak of drug resistant TB in New York City. The index patient died. 23 of 28 close contacts had evidence of new infection, and active drug‐resistant TB disease developed in 6 of the 23 infected contacts.
• Federal funding for TB control decreased continuously from the late 1960s through the mid‐1980s, and most sanatoriums closed during this period. From the mid‐1980s through the early 1990s, there was an unexpected nation‐wide increase in people with active TB.
• In 1995, the World Health Organization published its DOT strategy to help curb the TB epidemic. The WHO director later called the strategy the “…most important public health breakthrough of the decade in terms of lives…saved.”
• In the early to mid‐1990s, federal funding for TB control increased dramatically in response to these large outbreaks. Federal, State, and Local TB programs were rebuilt and strengthened, and TB rates have decreased since then.
• More recently, in 2012 the FDA approved Bedaquiline for treating MRD‐TB. This was the first TB medication that was been approved for treating TB in more than forty years.
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Globally, in 2018…
• 10 million people fell ill from TB
• 1.2 million people died from TB
• 1 in 3 people needing treatment for drug resistant TB received treatment
• 1.7 billion people are estimated to have latent TB infection (LTBI)
that’s over 27,300 people every day
that’s over 4,300 people every day
Drug resistant TB treatment success rate was 56%
"The End TB Strategy milestones…can only be achieved if TB diagnosis, treatment and prevention services are provided within the context of progress towards universal health coverage, and if there is
…action to address…determinants that influence TB epidemics and their socioeconomic impact."
that’s 23% of the world’s population
Global TB Epidemiology
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Slide 7: Global TB Epidemiology, 2018
• [Note: This slide has four animations to add emphasis. Purple text will appear under each bullet point after you advance the slide (click) once.]
• In 2019 the WHO (World Health Organization) released their annual Global Tuberculosis Report, which is complied with information collected in 2018.
• [Read through the slide]
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• 30 high TB‐burden countries accounted for 87% of new TB cases
1. India2. China3. Indonesia4. Philippines5. Pakistan6. Nigeria7. Bangladesh8. South Africa
Estimated TB incidence rates, 2018• 8 of the 30 high TB‐burden countries accounted for 67% of new TB cases
Global TB Epidemiology, 2018
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Slide 8: Global TB Epidemiology, 2018
• In the 2019 report, the WHO named 30 high TB‐burden countries, which accounted for 87% of all new TB cases worldwide.
• Eight of the 30 high TB‐burden countries accounted for two thirds of the total number of new TB cases globally in 2018. These countries are India (27%), China (9%), Indonesia (8%), Philippines (6%), Pakistan (6%), Nigeria (4%), Bangladesh (4%), and South Africa (3%).
• This map shows the estimated new TB case rates, per 100,000 population, for 2018. The darker green countries had a higher rate of new TB cases in 2018.
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www.bcgatlas.org
• Prevents disseminated disease in infants and young children
• Protection lasts for 10‐15 years; response has been shown to wane with time if not exposed to TB
• Among the 30 high TB burden countries, BCG vaccination coverage ranged from 52% (Papua New Guinea) to 99% (Bangladesh, China, Thailand and the United Republic of Tanzania)
Estimated BCG vaccine coverage, 2018
BCG (Bacillus Calmette–Guérin) Vaccine
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Slide 9: BCG (Bacillus Calmette–Guérin) Vaccine
• First used in 1921, BCG is the only vaccine for TB, and is currently only used in high TB prevalence countries.
• BCG protection can last for 10 to 15 years and is effective in preventing disseminated disease, such as TB meningitis and miliary TB, in infants and young children. The efficacy of BCG is believed to wane with time, especially if the person is not exposed to TB.
• According to the WHO, 153 countries recommended BCG vaccination in 2018, and 113 countries reported coverage of at 90%.
• Among the 30 high TB burden countries, coverage ranged from 52% in Papua New Guinea to 99% in Bangladesh, China, Thailand and the United Republic of Tanzania.
• This map shows the estimated percentage of BCG vaccine coverage in 2018.
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The darker green countries have a higher percentage of BCG vaccination.
• [Use the BCG World Atlas (www.bcgatlas.org) to find out current and past BCG vaccination policies and practices for over 180 countries.]
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United States TB EpidemiologyReported People with TB, 1988–2018
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Slide 10: United States TB Epidemiology: Reported People with TB, 1988‐2018
• The blue bars show the number of people with TB reported in the U.S. in the past 30 years.
• The dotted green line shows the rate, or the number of people with TB reported per 100,000 people.
• The number of people with TB and rate increased during the late 1980s and early 1990s, followed by decreased numbers of people with TB since 1992.
• [Question for Audience] What caused the increase in the number of people with TB starting in mid‐1980?
• [Answer] This resurgence of TB was driven by weakened capacity for TB control due to decades of funding cuts, and the emergence of HIV in the U.S.
• The colored percentages above the space between each bar show the annual
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percent change in rate. Red numbers indicate increasing or no change in rate, while green numbers indicate a reduction in rate from the previous year.
• [Question for Audience] Why do you think the change in rate has slowed in the past 6 years? What does this mean for TB elimination in the U.S.?
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United States TB EpidemiologyU.S.‐Born vs. Foreign‐Born People with TB, 1993–2018
(# / 100,000 population)
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Slide 11: United States TB Epidemiology: U.S.‐born vs. Foreign‐born People with TB, 1993‐2018
• This graph compares the number and rate of U.S.‐born and foreign‐born people with TB, reported in the U.S. in the past 25 years (1993‐2018).
• 2001 was the first year that people with TB born outside of the U.S. out‐numbered their U.S.‐born counterparts. Since then, there has been a steady decrease in the number of U.S.‐born people with TB, while the number of foreign‐born people with TB has remained relatively even.
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Nationally, in 2018…
• 9,025 people fell ill from TB
• The rate was 2.8 people with TB per 100,000 population
• 605 people had INH resistant TB
• 26% of people with TB were > 65 years old
that’s over 24 people diagnosed each day
that’s only a 0.75% decrease from 2017
98 people had multi‐drug resistant (MDR) TB
in other words, for every 100,000 people aged > 65, 4.5 had active TB
United States TB Epidemiology
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Slide 12: United States TB Epidemiology
• [Note: This slide has four animations to add emphasis. Blue text will appear under each bullet point after you advance the slide (click) once.]
• The United States reported 9,025 people with TB in 2018, that's over 24 people every day.
• The rate of TB in the U. S was 2.8. This represents only a 0.75% decrease from 2017.
• 605 people had TB that was resistant to isoniazid, one of the four first‐line drugs required for TB treatment. An additional 98 people had multi‐drug resistant TB, or MDR‐TB. This means they were resistant to at least isoniazid and rifampin.
• 26% of people with TB were 65 years or older, which is a case rate of 4.5
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United States – 30%
Mexico – 13%
Philippines – 9%
India – 7%
Vietnam – 6%
China – 4%
Guatemala – 2%
Ethiopia – 2%
Honduras – 2%
Others (22) – 26%
Percent of people with TB in the U.S., by country of birth, 2018
TB Rates by State, 2018
United States TB Epidemiology
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Slide 13: United States TB Epidemiology
• On the left, the map shows the TB case rates reported by each state in the U.S. in 2018. The darker the color, the higher the TB case rate is for the respective state.
• The table on the right shows the percent of people with TB in the U.S. in 2018, by country of birth. Those born in the United States represent the largest portion of reported people with TB, at 29.5%, followed by those born in Mexico (13.3%), Philippines (8.6%), India (6.9%), Vietnam (5.6%), China (4.2%), Guatemala (2.3%), Ethiopia (1.7%) and Honduras (1.6%). The remaining 22 countries represent 30% of reported people with TB in the U.S. in 2018.
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Michigan TB EpidemiologyNumber of Persons with TB, 1988–2019
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Slide 14: Michigan TB Epidemiology: Reported People with TB, 1988‐2019
• This graph shows the number of reported people with TB and the rate in Michigan in the past 31 years.
• In Michigan, the number of reported people with TB was on a steady declining through 2014. However, this number has recently plateaued and remained relatively steady for the past 6 years.
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In Michigan in 2019…
• 132 people fell ill from TB
• The rate was 1.3 people with TB per 100,000 population
• 59% had pulmonary TB and 30% had extrapulmonary TB
• 6 people had INH resistant TB
that’s a 22% increase from 2018
that’s a 18% increase from 2018
11% had both pulmonary and extrapulmonary TB
1 person had multi‐drug resistant (MDR) TB
Michigan TB Epidemiology
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Slide 15: Michigan TB Epidemiology
• [Note: This slide has four animations to add emphasis. Green text will appear under the first bullet point after you advance the slide (click) once.]
• Michigan reported 132 people with TB in 2019, which is a 22% increase from 2018.
• The rate was 1.3 people with TB per 100,000 people
• 59% of people with TB had pulmonary TB, where the disease was only found in their lungs. 30% of people with TB had extra‐pulmonary TB, where the disease was found in some other part or parts of the body, other than the lungs. 11% of people with TB had TB in both their lungs and at least one other part of their body.
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• 6 people had TB that was resistant to isoniazid, one of the four first‐line drugs required for TB treatment. An additional 1 person had multi‐drug resistant TB, or MDR‐TB. This means they were resistant to at least isoniazid and rifampin.
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United States – 44%
India – 11%
Bangladesh – 4%
China – 4%
Yemen – 4%
Myanmar – 3%
Philippines – 3%
Others – 27%
Percent of people with TB in Michigan, by country of birth, 2019
TB Counts and Rates by County, 2019
Michigan TB Epidemiology
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Slide 16: Michigan TB Epidemiology
• This map shows TB counts and rates for each county in Michigan in 2019.
• The grey dots represent one person, although the location is not related.
• The darker shaded colors represent counties with higher TB case rates.
• Case rates are calculated based on the total number of people in each county.
• For example, Ostego County and Kalamazoo County each reported 1 person with TB in 2019. However, because Ostego County has a relatively small population size, compared to Kalamazoo County, Ostego County’s rate of TB is much higher, and the color on the map is much darker.
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• This pie graph shows the percent of people with TB in Michigan in 2019, by country of birth. 56% of persons with TB were born outside of the U.S. The most common countries of birth, other than the U.S., were India (11%), Bangladesh (4%), China and Yemen (both 4%).
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Other* ‐ 44%
None ‐ 35%
Diabetes ‐ 14%
Excess alcohol use ‐ 13%
Drug use ‐ 13%
Known contact ‐ 11%
Viral hepatitis ‐ 7%
Homelessness ‐ 6%
HIV+ ‐ 5%
COPD ‐ 4%
Smoking ‐ 2%
Percent of people with TB in Michigan, by comorbidity and risk factor, 2019
Michigan TB EpidemiologyComorbidities & Risk Factors, 2019
*Other: Resident of long‐term care facility, previous diagnosis of TB disease, incomplete LTBI treatment, other immunosuppression17
Slide 17: Michigan TB Epidemiology, Comorbidities & Risk Factors, 2019
• 56% of people with TB in Michigan reported having at least one comorbidity or risk factor.
• Diabetes mellitus is a significant risk factor for progressing from TB infection to TB disease and remains the most common comorbidity for TB disease in Michigan.
• Incomplete LTBI treatment and social risk factors such as substance abuse, contact to a person with infectious TB disease and homelessness, can all contribute to TB infection and progression to TB disease. These may also affect case management and treatment completion.
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Epidemiology Question
Over 130 cases of TB were reported in Michigan in 2019.
TRUE FALSE
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II. Mycobacterium tuberculosis Transmission & Pathogenesis
• Mycobacterium tuberculosis transmission
• Transmission & pathogenesis timeline
• TB infection TB disease
• Latent TB infection (LTBI) treatment regimens
• LTBI vs. TB Disease
• Quiz question
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Airborne droplets
1. Route
2. CyclePerson to person
3. Reservoir
Human body
M. tuberculosis Transmission
Route
Airborne Droplets
Cycle
Person to Person
Reservoir
Human Body
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Slide 20: Mycobacterium tuberculosis Transmission
• Tuberculosis disease is caused by a bacterium called Mycobacterium tuberculosis (or, TB bacteria).
• There are there main parts for successful transmission of TB bacteria:
o Reservoir – TB bacteria can “hide” in the human body for decades as latent TB infection, or LTBI.
o Route – When LTBI activates or progresses to TB disease, TB bacteria can be transmitted through the air via tiny droplets of moisture when a person coughs, sneezes, shouts, or sings. TB is only spread through the air, and not by touching objects or clothing, sharing food or beverages, or kissing.
o Cycle – The transmission cycle continues when the bacteria move from person to person. Only those with active TB disease of the lungs can transmit Mycobacterium tuberculosis.
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Infectiousness
ExposureEnvironment
M. tuberculosis Transmission Factors
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Slide 21: TB Bacteria Transmission Factors
• Three factors determine the likelihood of Mycobacterium tuberculosistransmission:
1. Infectiousness: How infectious was the person?o Site of disease (must be lungs, airway, or larynx)o Was the person coughing?o Was their sputum positive for acid‐fast bacilli?
2. Environment: Where was the infectious person?o Was there ventilation, or open windows/doors?o Was there positive or negative air pressure, or recirculation of air
containing bacteria?o Was the infectious person inside a small, enclosed space?
3. Exposure: How long were you in the same area with the infectious person?
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o Timeo Distanceo Number of visits
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Slide 22: Exposure
• On the transmission side: On day zero, the infectious person (man) is singing or laughing near a susceptible host (woman). She inhales airborne droplets of moisture containing TB bacteria.
• On the pathogenesis side: TB bacteria are inhaled into the lungs and travel to the host’s alveoli.
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Slide 23: Initial Infection
• Approximately 1‐22 days after exposure, the host’s primary immune response begins to detect the TB bacteria.
• On the transmission side:o Culture and sputum smears/AFB are negative and the host is not infectious.o Because the host does not know that they were exposed to an infectious
person with TB, they do not think to get treatment.
• On the pathogenesis side:o Macrophages ingest and contain some TB bacteria, but the immune system is
not recognizing TB bacteria specifically, so a TST or IGRA will be negative.o In 5‐10% of people exposed, the primary immune response (macrophages)
will eliminate the infection and they will never have a positive TB test.o In most people (about 80‐90%), a few TB bacteria will survive attack by the
macrophages and travel through the bloodstream or lymph to other organs in the body. This process of dissemination prepares the immune system for a secondary immune response, which involves memory cells.
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Slide 24: Active TB Disease
• Approximately 23‐56 days post‐exposure, those with suppressed immune systems (about 5‐10%) will develop active TB disease.
• On the transmission side:o At this point, the host could be infectious and sputum smears/AFB could be
positive if the bacteria remained in their lungs. o Cultures should be positive, and multi‐drug treatment is required to stop the
spread of TB.
• On the pathogenesis side:o TB disease is most commonly found in the lungs, called pulmonary TB.
However, TB disease can also be found outside of the lungs, such as the brain, spine, bone, or kidney; this is called extrapulmonary TB. The severity and type of symptoms depends on the site and extent of TB disease.
o Because the secondary immune response has been primed against the TB bacteria, TB tests are likely to be positive.
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Slide 25: LTBI
• Most people exposed to Mycobacterium tuberculosis (about 90‐95%) will develop latent TB infection, or LTBI.
• On the transmission side:o Those with LTBI will have negative cultures and sputum smears/AFB and are
not infectious. However, treatment for LTBI is highly recommended.
• On the pathogenesis side:o LTBI occurs when the macrophages from the original response form a barrier
around the TB bacteria, attempting to contain the infection. These barriers are called granulomas.
o Because the secondary immune response has also been primed against the TB bacteria, TB tests will most likely be positive in those with LTBI.
o Because the granulomas are keeping the infection under control, the person will not be experiencing any symptoms.
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Slide 26: TB Activation
• Five percent of people with LTBI will develop active TB disease within two years of exposure. An additional 5% will develop active TB disease within their lifetime.
• It is crucial that those with LTBI are treated, to prevent them from developing active TB disease and continuing the TB transmission cycle.
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Slide 27 Latent Tuberculosis Infection (LTBI)
• LTBI is defined as the state of persistent immune response to Mycobacterium tuberculosis without evidence of clinical TB disease.
• Unfortunately, there is no direct measurement tool for LTBI. Those with positive TB tests (TST or IGRA) need further evaluation to first rule out active TB disease before they are diagnosed with LTBI.
• Up to 13 million people in the US have LTBI, and more than 80% of the people with active TB disease in 2017 were the result of untreated LTBI.
• Identifying persons with LTBI is important for TB elimination because TB disease can be prevented by treating LTBI.
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Slide 28: TB Infection to TB Disease
• TB activation occurs in approximately 5‐10% of those with untreated LTBI.
• Risk of TB activation is much higher in some, especially those who are immunosuppressed. Risk factors for TB activation include:
o HIV‐infectiono Age (elderly, infants, children)o Dialysiso TNFα (tumor necrosis factor alpha) medications (Humira, Embrel, Remicade)o Smokingo Silicosiso Diabetes mellituso Severe kidney diseaseo Organ transplanto Persons who abuse drugs and/or alcohol
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Drug(s) Duration Frequency Total Doses
INH and RPT (3HP) 3 months Once‐weekly 12
RIF 4 months Daily 120
INH
9 monthsDaily 270
Twice‐weekly* 76
6 monthsDaily 180
Twice‐weekly* 52
INH = isoniazid, RPT = rifapentine, RIF = rifampin*Directly‐observed therapy (DOT) should be used for intermittent dosing
Treatment Regimens for Latent TB Infection
CDC Recommends Use of 3HP: By DOT or self‐administered
therapy in persons >2 years
In children and adolescents, 2‐11 years old
In persons with LTBI who are living with HIV/AIDS and taking antiretroviral medications with acceptable drug interactions with RPT
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Slide 29: Treatment Regimens for Latent TB Infection
• There are three LTBI treatment regimens recommended by the CDC.
• Providers should choose the appropriate regimen based on coexisting medical conditions, drug‐drug interactions, and the likelihood the person will consistently take their doses on time.
• The CDC now recommends use of 3HP: 1) by directly observed therapy or self‐administered therapy in persons older than two years; 2) in children 2‐11 years old; 3) in persons with LTBI and HIV taking antiretroviral meds with acceptable RPT drug interactions.
• For persons who are at especially high risk for progressing to TB disease or are unlikely to take their doses on time consistently, directly observed therapy (DOT) should be considered. DOT is also strongly recommended for intermittent dosing of INH.
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Person with Latent TB Infection Person with TB Disease
Has a small amount of contained TB bacteria in their
body
Has a large amount of active TB bacteria in their body,
not contained
Cannot spread TB bacteria to others
(Not Infectious)
May spread TB bacteria to others
(Infectious)
Does not require respiratory isolation May require respiratory isolation
Does not feel sickMay feel sick and have symptoms
(cough, hemoptysis, fever, weight loss, etc.)
Chest x‐ray is typically normal Chest x‐ray may be abnormal
Sputum smears and cultures are negative Sputum smears and cultures may be positive
Recommend treatment for LTBI:
One or two medications
Required treatment for TB Disease:
Four medications
Usually has a positive TST or IGRA
Not a TB case (but could become one) A TB case
LTBI vs. TB Disease
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Slide 30: LTBI vs. TB Disease
A person with latent TB infection: • Has a small amount of TB bacteria in their body contained within
granulomas.• Is not infectious and cannot spread TB bacteria to other people.• Does not require respiratory isolation, nor do they feel sick.• Chest x‐ray is typically normal, and sputum smears and cultures are
negative.• Should take treatment for TB infection to prevent themselves from
developing TB disease later. Treatment for LTBI is one to two medications at most and can be completed in as little at 12 weeks.
• Usually have a positive TB test (TST or IGRA).• Is not a case of TB disease but could become one.
A person with active TB disease:• Has a much larger amount of TB bacteria in their body, and the bacteria
are not contained.
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• May spread TB bacteria to others, depending on the site of disease (pulmonary vs. extrapulmonary) and their infectiousness.
• May require respiratory isolation, depending on the site of disease (pulmonary vs. extrapulmonary).
• May feel sick, with symptoms like cough, hemoptysis, fever, and weight loss, among others.
• Their chest x‐ray may be abnormal, depending on if they have pulmonary disease and the severity of their disease.
• Sputum smears and cultures may be positive. • Require treatment with multiple antibiotics for 6‐12 months.• Usually have a positive TB test (TST or IGRA).• People with suspected or confirmed TB disease should be reported to the
local health department.
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Transmission & Pathogenesis Question
Which of the following patient characteristics indicate LTBI, TB disease, or both? Choose one of the following:
LTBITB Disease
Both LTBI and TB Disease
Patient Characteristics Type of TB
Has a positive TST or IGRA
May spread TB bacteria to others
Has TB bacteria in his/her body
Is NOT a case of TB…yet
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III. Testing and Evaluating for TB
• TB evaluation process
• Testing for TB: TST & IGRA
• Screening for TB in healthcare workers
• Quiz question
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Medical History & Physical Exam
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TB Evaluation ProcessMedical History & Physical Exam
Signs & SymptomsProductive, prolonged cough
Chest painHemoptysisFever/ChillsAppetite loss
Unexplained weight lossNight sweats
Fatigue
Medical HistorySocial & travel history
Potential exposure or family history of TBPast TB treatment
Demographic risk factorsOccupational information about the patient
Medical conditions that increase the risk of TB
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Slide 33: TB Evaluation Process: Medical History & Physical Exam
• Most screening tools and tests cannot individually confirm or deny M. tuberculosisinfection or TB disease; however, a complete evaluation using all available methods can give a good indication.
• Each TB evaluation is different, and physicians may choose to use different methods, or a different order of steps, for diagnosing LTBI and active TB disease. The TB evaluation process typically begins with a complete medical history and physical exam.
• Medical History:o Discuss social, travel, or other opportunities for previous exposure to TB,
reminding the patient about signs and symptoms that other people around them may have shown.
o Obtain information on previous diagnosis of LTBI or TB disease and contact the local health department for information or confirmation of LTBI or TB disease diagnosis and treatment.
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o Account for any demographic or occupational risk factors that may increase the likelihood that the patient has been exposed to TB, such as country of origin, age, racial group, or work in settings of high‐risk for TB exposure.
o Several medical conditions can increase the risk of progressing from LTBI to TB disease, including HIV, diabetes, those taking immune‐suppressive therapies, drugs or alcohol abuse, and certain types of cancers.
• Signs and Symptoms:o Ask the patient if they have any symptoms of TB disease, and if so, how long
they have been experiencing said symptoms. o Symptoms of pulmonary TB disease can include productive, prolonged
cough, chest pain, hemoptysis, fever/chills, appetite loss, unexplained weight loss, night sweats, and fatigue.
o Symptoms of extra‐pulmonary TB disease vary according to disease site. For example, TB in the kidney may cause blood in urine, TB meningitis may cause headache or confusion, TB of the spine may cause back pain, TB of the larynx can cause hoarseness.
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Medical History & Physical Exam
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TST or IGRA
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TB Evaluation ProcessTesting
Interferon‐Gamma Release Assay (IGRA)• Blood test measures immune response
to specific TB proteins• More specific than TST, can cost more
Tuberculin Skin Test (TST)PPD injected intradermally; reaction is
measured 48‐72 hours later
34
Slide 34: TB Evaluation Process: Testing
• The second step in the TB evaluation process is testing for TB. Currently available TB tests cannot distinguish between LTBI, active TB disease, or previously treated TB.
• As discussed in the pathogenesis section, it takes 2 to 8 weeks after exposure to the TB bacteria for the secondary immune response to recognize and react to a TB protein. Therefore, TB tests may not be positive for up to eight weeks after exposure.
• For the tuberculin skin test, or TST, purified protein derivative is injected intradermally, and the immune response, or reaction to the PPD, is read 48‐72 hours after administration.
• The Interferon‐Gamma Release Assay, or IGRA, is a blood test, which measures the immune response to more specific TB proteins. We will talk more about the TST and IGRA throughout the workshop.
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Medical History & Physical Exam
X‐Ray
2 3
TST or IGRA
1
TB Evaluation ProcessChest X‐Ray
Chest Radiography• Abnormalities often seen in apical or posterior segments of upper lobe or superior segments of lower lobe
• Lesions can appear anywhere in the lungs and may differ in size, shape, density and cavitation, especially immunosuppressed persons
35
Slide 35: TB Evaluation Process: Chest Radiography
• The third step in the TB evaluation process is the chest x‐ray, which is useful for diagnosing pulmonary TB disease.
• In some instances, a computerized tomography, or CT scan, may provide more detailed images of different parts of the body that cannot easily be seen on a standard chest radiograph.
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Medical History & Physical Exam
X‐Ray
2 3 4
Specimen Collection
TST or IGRA
1
TB Evaluation ProcessSpecimen Collection
Pulmonary TBSputum: 3 specimens, 8‐24 hours apart, at least 1 in the early morning:
Coughing Sputum induction Gastric washing/aspiration Bronchoscopy
Extra‐pulmonary TBUrine, cerebrospinal fluid,
pleural fluid, pus, or biopsies
36
Slide 36: TB Evaluation Process: Specimen Collection
• The fourth step in the TB evaluation process is specimen collection. These methods depend on where the disease is thought to be in the body.
• Sputum specimen collection methods for pulmonary TB disease include:o Coughing: The most common method used for sputum collection. Patients
should be instructed to bring the sputum material up from the lungs and that mucus from the nose or throat and saliva are not good specimens.
o Sputum induction: Used for patients unable to cough‐up sputum. Patients inhale a warm, sterile saline solution, which induces the coughing reflex.
o Gastric washing/aspiration: This is another method for patients unable to cough‐up sputum, or children. A tube is inserted through the mouth or nose and into the stomach to recover sputum that was coughed into the throat and then swallowed.
o Bronchoscopy: A bronchoscopy allows visualization of the inside of a person’s airways and might be needed for specimen collection, especially if previous results have been non‐diagnostic and doubt exists as to the
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diagnosis.
• For extra‐pulmonary TB disease, common specimens include urine, cerebrospinal fluid, pleural fluid, pus, or biopsies.
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Medical History & Physical Exam
X‐Ray
2
Drug Susceptibility Testing (DST)Helps clinicians to choose
appropriate regimen
3 4
Specimen Collection
NAAT
CultureAFB Smear
DSTTST or IGRA
1 8
Acid Fast Bacilli (AFB) SmearRapid test, but less accurate than culture
5 6
Nucleic Acid Amplification Test (NAAT)•More accurate than AFB smear, faster than culture• Requires technical training, may be cost‐prohibitive
Culture•Gold standard
• Takes up to 8 weeks
7
TB Evaluation ProcessLaboratory
37
Slide 37: TB Evaluation Process: Laboratory Procedures
• The last four steps in the TB evaluation process take place in a mycobacteriology lab using the previously mentioned specimens. These methods can be very accurate for diagnosing TB disease; however, they’re also more time consuming and expensive.
• The Acid‐Fast Bacilli (AFB) Smear is the most rapid of the laboratory tests; however, it is less accurate than culture.
o Specimens are smeared onto a glass slide and stained. The stained slide is examined for AFB under a light microscope.
o AFB smear cannot confirm diagnosis of TB disease because non‐tuberculous mycobacteria will also be detected using the AFB smear. In addition, a negative smear does not exclude TB disease because it is not the most accurate test.
• The Nucleic Acid Amplification Test (NAAT) is a rapid test for detecting Mycobacterium tuberculosis genetic material.
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o NAAT is more accurate than the AFB smear and faster than culture; however, it requires training that is more technical and may be cost‐prohibitive.
• Culture‐based identification is the gold standard for diagnosing tuberculosis disease. The time it takes a culture to turn positive for TB depends largely on the number of bacteria that are initially added, but since Mycobacterium species grow very slowly, it usually takes 2‐8 weeks to get a culture result.
• Drug Susceptibility Testing (DST) is done when a culture first turns positive.o DST helps clinicians make sure they are prescribing an appropriate drug
regimen for their patient and helps prevent drug resistance and treatment failure.
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Different Types of Mycobacteria
Mycobacterium tuberculosis Complex (MTC)• 10 genetically related mycobacteria species that can cause TB disease
• Examples: M. tuberculosis, M. bovis, M. africanum, M. canetti
Mycobacterium marinum infection on the arm of a fish‐tank worker
Non‐Tuberculous Mycobacteria (NTM)• All other mycobacterial species that do not belong to MTC
• Examples: M. avium complex (MAC), M. kasassii, M. marinum
• Also known as environmental mycobacteria, atypical mycobacteria, or MOTT (Mycobacteria Other Than Tuberculosis)
38
Slide 38: Different Types of Mycobacteria
• Mycobacterium tuberculosis complex consists of 10 genetically related mycobacteria that can cause TB disease.
• The 10 are: M. tuberculosis,M. africanum,M. bovis,M. microti,M. canettii,M. caprae,M. pinnipedii,M. suricattae,M. mungi,M. dassie, andM. oryx.
• NTMs, or non‐tuberculous mycobacteria, are mycobacteria that do not cause tuberculosis or leprosy. NTMs (also known as MOTT, environmental mycobacteria, or atypical mycobacteria) are often found in water and soil.
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Testing for TBMantoux Tuberculin Skin Test (TST)
PPD (purified protein derivative)• Proteins from dead Mycobacterium bovis• Not a vaccine• Store at 2‐8°C, protected from light• Discard 28 days after opening• Mark/label vial after opening
Process• Inject 0.1 mL PPD intradermally• Immune system produces a delayed reaction to the PPD Read test 48‐72 hours after administration Measure induration transversely, across the arm
BCG and most NTMs (non‐tuberculosis mycobacteria) can cause a false‐positive TST result 39
Slide 39: Testing for TB: Mantoux Tuberculin Skin Test (TST)
• There are two methods available for testing for M. tuberculosis infection in the United States. The first, the TST, or tuberculin skin test, is the most commonly used test.
• The TST consists of injecting PPD, or purified protein derivative, intradermally. PPD is the product of heat‐killed Mycobacterium bovis and is not a vaccine.
• When the PPD is injected intradermally in a person infected with mycobacteria, it produces a delayed type of hypersensitivity reaction. This reaction begins about 5‐6 hours after injection and peaks 2‐3 days later.
• BCG and NTMs (non‐tuberculosis mycobacteria) can cause a false‐positive result.
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TST Interpretations & Risk Factors
≥ 5 mm is positive in ≥ 10 mm is positive in ≥ 15 mm is positive in
• HIV positive persons
• Recent contacts to persons with infectious TB
• Persons with fibrotic changes on a chest radiograph
• Organ transplant recipients and other immunosuppressed persons (including patients taking a prolonged course of oral or intravenous corticosteroids or TNF‐a antagonists)
• Recent arrivals (within the past 5 years) from high incidence countries
• Injection drug users
• Residents and employees of high‐risk congregate settings (hospitals, long‐term care facilities, residential facilities for patients with immune‐compromising conditions, correctional facilities, homeless shelters)
• Mycobacteriology laboratory personnel
• People with certain medical conditions that place them at high risk for TB (silicosis, diabetes mellitus, severe kidney disease, certain types of cancer, and certain intestinal conditions)
• Children younger than 5 years of age
• Infants, children, and adolescents exposed to adults at high risk for developing TB disease
• People with no known risk factors for TB disease
• HCWs who are otherwise at low risk for TB disease and who received baseline testing at the beginning of employment as part of their TB screening program
40
Slide 40: TST Interpretations & Risk Factors
• TST interpretation depends on the measurement (in millimeters) of induration and the person’s risk of acquiring TB infection or their risk of progression to TB disease, if infected.
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Testing for TBInterferon‐Gamma Release Assay (IGRA)
• Blood test measures immune response to highly specific TB proteins
• Two FDA‐approved IGRA tests:1. QuantiFERON®‐TB Gold Plus (QFT®‐Plus)2. T‐Spot®.TB Test (T‐Spot)
• IGRA test result interpretation is discussed in detail in the Testing for TB Infection Video
Some NTMs can cause a false‐positive IGRA result, but not as many as TST.
41
Slide 41: Testing for TB: Interferon‐Gamma Release Assay (IGRA)
• The Interferon‐Gamma Release Assay, or IGRA, is a blood test, which measures a person’s immune response to specific TB proteins.
• Unlike the TST, IGRA reactions occur outside of the body, in a controlled lab, and do not cross‐react with as many mycobacteria species.
• There are two types of IGRAs on the market: The first is the QuantiFERON‐TB‐Gold Plus, or “QFT‐Plus”. Second is the T‐Spot.TB Test, or T‐Spot.
• Some NTMs can cause a false‐positive IGRA result, including M. kansasii, M. szulgai, M. marinum, and M. leprae.
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CDC RecommendationsWho to Test & Which Test to Use
Risk of TB infection…
• Household contact or recent
exposure to an active case
• Mycobacteriology lab personnel
• Immigrants from high‐burden
counties
• Residents/employees high‐risk
congregate settings
Risk of developing TB if infected…
• Age (< 5 years)
• HIV+
• On immune‐suppressive therapy
• Abnormal CXR or prior TB
• Silicosis
• Diabetes
• Chronic renal failure
• Intravenous drug use
• Prevalence of BCG vaccination• Expertise of staff and/or laboratory• Test availability• Patient perceptions• Programmatic concerns
Considerations when choosing a TST or IGRA
Low Risk
High Risk
42
Slide 42: CDC Recommendation: Test High Risk
• The CDC recommends testing those at high risk for TB infection, and those at high risk for advancing from TB infection to TB disease.
• This graphic shows the different populations at risk of TB infection (left), and the different risk factors that promote reactivation of LTBI to TB disease (right). The risk levels decrease going down.
• Both TST and IGRA have their merits and drawbacks. Considerations when choosing a TB test should be based on the reason and context for testing, test availability, population being tested, and overall cost effectiveness of testing.
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Population TST IGRA
InfantsSame dosage as adults;
may receive false‐negativesNot Recommended
Children < 2 years Recommended Not Recommended
Occupational screening Either test
Unlikely to return for TST reading Not Recommended Recommended
Recent contacts to persons with TB disease who need follow‐up testing
Not Recommended Recommended
History of BCG (vaccine or cancer therapy) Not Recommended Recommended
TNF‐α meds (Humira/Enbrel/Remicade) Wait one month after prolonged steroid use
HIV/AIDs Be aware of false‐negativesDraw 2X rec. volume of
blood
Pregnant or breastfeeding women Both are safe to use
History of positive TB test Do not administer either test; ensure disease was ruled‐out
Live‐virus vaccinesUse same day as live‐virus vaccine or 4‐6 weeks after; wait at
least one month after smallpox vaccine
CDC RecommendationsTesting Certain Populations
43
Slide 43: CDC Recommendations: Testing Certain Populations
• Depending on the population being tested, one test may be recommended over the other. This table reviews which test is recommended by the CDC in certain populations.
• When administering a TST, infants and children can take the same strength and dosage of PDD as adults; however, keep in mind that infants are more likely to give a false‐negative reaction. IGRAs are currently not recommended by the CDC for use in infants and children five years old or younger.
• IGRAs are recommended for those unlikely to return for their TST reading, recent contacts to persons with TB disease, and those with a history of BCG use, either as a vaccine or for cancer therapy. IGRAs will not give a false‐positive result due to BCG vaccination. Because it is unclear how long BCG protection can last for, a positive TST result in a patient with history of BCG vaccination should be interpreted as truly positive and that patient should be evaluated for TB infection.
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• Both the TST and IGRA can be used in patients who are on TNF‐α (tumor necrosis factor alpha) medications, such as Humira, Enbrel, and Remicade. Wait one month after stopping TNF‐α medications before testing for TB.
• If you are using the TST to test immunocompromised persons, such as those with HIV infection, be aware of false negatives. If you are using an IGRA in immunocompromised persons, draw twice the recommended volume of blood. This is because both the TST and IGRA rely on the response of a healthy immune system.
• Both TST and IGRA are safe to use in pregnant and breastfeeding women.
• Those with a documented history of a positive TB test should not receive another TB test (TST nor IGRA). You should ensure that TB disease was ruled‐out and/or they have been treated.
• TB tests can be administered the same day as a live‐virus vaccine, or within 4‐6 weeks after administration of a live‐virus vaccine. Wait at least one month after smallpox vaccination before giving a TB test.
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TST IGRA
Technical error: incorrect application, reading, or interpretation
Technical error: incorrect specimen handling and/or processing
Age: less than 6 months or elderly Age: < 2 years or elderly
Those recently infected with M. tuberculosis (within the last 8 weeks)
Absence of normal immune response. May be due to: TNF‐α medications, HIV/AIDS, recent live‐virus vaccination, bacterial, viral, and fungal illnesses, or severe TB disease
Chronic renal failure
Diseases affecting lymphoid organs, such as Hodgkin’s disease, lymphoma, chronic leukemia, sarcoidosis
Stress (surgery, burns, mental illness, graft‐versus‐host reactions)
False‐Negative TB Tests
When a TB test is interpreted as “negative” when there actually is TB infection/disease present.
False‐Negative TB tests can be due to…
44
Slide 44: False‐Negative TB Tests
• False‐negative TB tests are when a TB test is interpreted as “negative,” when there is TB infection or disease present.
• This table shows examples of how false‐negative test can occur in both TST and IGRA tests.
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When a TB test is interpreted as “positive” when there actually is no TB infection/disease present.
False‐Positive TB tests can be due to…
TST IGRA
Technical error: incorrect application,reading, or interpretation
Technical error: incorrect specimen handling and/or processing
Infection with NTMsInfection with M. kansasii, M. szulgai,
M. marinum, and M. leprae
History of BCG vaccine/use
Administration of incorrect solution
False‐Positive TB Tests
45
Slide 45: False‐Positive TB Tests
• False‐positive TB tests are when a TB test is interpreted as “positive,” when there is no TB infection or disease present.
• This table shows examples of how false‐positive test can occur in both TST and IGRA tests.
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1. Person infected with Mycobacterium tuberculosis
2. First TST: Negative Reaction
3. Second TST:Positive Reaction
Considered a “boosted reaction”You can assume TB infection occurred a long time ago.
Immune memory is now triggered for next response
Booster Phenomenon
Occurs in previously infected, older adults whose ability to react to tuberculin has waned over time
Over time, person’s ability to react to tuberculin lessens
Assume no exposure to M. tuberculosis during this time
Many years later
Up to 1 year later
46
Slide 46: Booster Phenomenon
• The booster phenomenon occurs mainly in adults who were infected with TB many years ago, yet their ability to react to tuberculin has waned over time. When receiving a TST, these people will have an initial negative reaction.
• If they are tested again within a year of the first test, they may have a positive reaction. This is considered a “boosted” reaction because the first TST “triggered the memory” of the immune system, boosting its ability to react to the second TST.
• These people should be considered for LTBI treatment if they fit into a high‐risk category for progression to TB disease.
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Baseline TST
Negative
Retest with TST 1‐3 weeks after first TST
result is read
NegativePerson probably does not
have LTBI
Serial TB testing is not recommended
PositiveReaction is boosted
PositivePerson probably has LTBI
Evaluate and rule‐out TB disease; treat for LTBI as necessary
Two‐Step TST
47
Slide 47: Two‐Step TST
• The two‐step TST is a testing strategy used to reduce the likelihood that a boosted reaction will be misinterpreted as a recent infection. Two‐step testing should be used for those who will be retested periodically, such as health care workers.
• If the reaction to the first test is negative, a second test should be repeated 1 to 3 weeks later. A positive reaction to the second test probably represents a boosted reaction, and the person should be classified as previously infected. This would not be considered a skin test conversion or a new TB infection; however, the patient would be a candidate for LTBI treatment.
• If the second test result is also negative, the person should be classified as having a negative baseline TST.
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Updated RecommendationsTB Screening in Health Care Personnel (HCP)
48
Screening Stage Updated 2019 CDC Recommendations Resources
Baseline screening and testing
• Test those without documented prior TB disease or LTBI• Screen all HCP with a symptom evaluation and adult TB risk assessment
2019 CDC Recommendations
TB Screening• TB sign and symptom review• Adult TB risk assessment
Possible Exposure• Work with your health department for suspected TB exposures and contact investigations
Annual Education• MDHHS TST Workshop• CDC online trainings
LTBI Diagnosis & Treatment• Recommended LTBI treatment regimens
• CDC's online LTBI resources hub
Post‐exposure screening and testing
• Symptom evaluation for all HCP• For HCP with a baseline negative TB test and no prior TB disease or LTBI, perform a test when exposure is identified; if that test is negative, repeat test 8–10 weeks after last exposure
Serial screening and testing for HCP
• Serial TB testing not routinely recommendedo Can consider for selected HCP groups
• Annual:o Screening for TB using an adult TB risk assessmento TB education for all HCP; include information about TB
exposure risk, signs and symptoms and LTBI treatment
Evaluation and treatment of positive test results
• Evaluate all positive tests for active TB disease• LTBI treatment is encouraged for all HCP with untreated LTBI• Emphasize shorter‐course regimens
Slide 48: Updated Recommendations: TB Screening in Health Care Personnel (HCP)
• In May 2019, the CDC and National TB Controllers Association updated the TB screening recommendations for health care personnel. The updated recommendations replace all TB screening recommendations from the 2005 MMWR "Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Healthcare Settings".
• This table shows the newly added recommendations from the 2019 document.
• The final column shows resources that can be used for each stage in the screening process.
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TB Screening in Heath Care Personnel
TB Test History Upon Hire Established Employee
Documented history of negative TB testwithin the past 12 months
One TST (to complete two‐step) or one IGRA
• Serial TB screening with adult risk assessment, sign and symptom review and TB education
• Serial TB testing notrecommended
No documented history of TB test
Two‐step TST or one IGRADocumented history of negative TB testolder than 12 months
Documented history of positive TB test or treatment for LTBI or active TB disease
Chest x‐ray(rule‐out active TB disease)
Baseline testing: Provides a basis for comparison if exposed to Mycobacterium tuberculosis, and Helps to detect and treat TB before employment begins.
49
Slide 49: TB Screening in Health Care Personnel
• It is important to establish a baseline TB test result for all health care personnel in order to facilitate possible workplace exposures in the future.
• The CDC recommends the two‐step TST or one IGRA before health care personnel begin their jobs.
• If you have an employee with a documented past positive, first give a chest x‐ray, then you will always screen thereafter with a sign and symptom review questionnaire. Do not use chest x‐rays or repeat TB tests on a previous positive to conduct serial screening.
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Slide 51: Review: TST vs. IGRA
• TSTo The TST consists of injecting PPD intradermally, which produces a delayed
reaction against the PPD proteins.o The test requires two or more patient visits, and results are available within
48‐72 hours after administration.o The TST can cause the booster phenomenon and reading of the induration is
subjective and can be affected by perception or bias.o The BCG vaccine and some NTMs can cause false‐positive test results;
however, the TST is not contraindicated for persons who have been vaccinated with BCG.
o Cold storage is required for the PPD; however, lab equipment and phlebotomy are not required for the TST.
o The TST can result in scarring or bad reactions, yet the price per test is low compared to the IGRA.
• IGRAo IGRAs are blood tests that measure the immune response to TB proteins in
whole blood.o IGRAs require only one patient visit, and results can be available within 24
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hours, depending on the processing lab.o IGRA tests will not boost each other (more than one IGRA test drawn close
together will not boost); however, TSTs have been shown to boost IGRAs. o Interpretation of the IGRA test is not subjective nor affected by perception or
bias.o The BCG vaccine and most NTMs do not cause false‐positive results. Cold
storage is not required for IGRA test kits nor shipping of specimens; however, phlebotomy and lab equipment are required.
o Because the IGRA reaction happens outside of the body, it cannot result in scarring or other adverse events, yet the price per test is high compared to the TST.
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Testing and Evaluating for TB Question
Characteristic Type of TB Test
Test used to detect TB infection
PPD is injected intradermally for this test
This test requires two or more patient visits
BCG vaccination may cause a false‐positive in this test
Immune status should be considered for this test
Match the characteristic with the type of TB test. Use the following type of TB test:
TSTIGRA
Both TST and IGRA
51
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IV. TB Case Management
• TB disease treatment
• Drug resistant TB
• Roles of the Local Health Department
52
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TB Disease Treatment
• First‐line anti‐TB drugs: • Isoniazid (INH)• Rifampin (RIF)• Ethambutol (EMB)• Pyrazinamide (PZA)
• Treatment can range from 6‐24 months, with doses ranging from 2‐7 days per week
• LHDs ensure therapy adherence through: Patient education Reinforcement Directly Observed Therapy (DOT)
53
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Drug Resistant TB
Drug‐resistant TB develops when the antibiotics used to treat TB are misused or mismanaged.
four
MDR TB
people
in 2018
in MI
had
DID YOU KNOW…DRUG‐RESISTANT TBResistant to 1 of 4 first‐line antibiotics used to treat TB. The most common is INH‐resistant TB.
MDR TBResistant to 2 of 4 first‐line antibiotics, isoniazid and rifampin.
XDR TB
MDR TB that is also resistant to at least 1 of the 3 second‐line antibiotics, including fluoroquinolones.
First‐line antibiotic Second‐line antibiotic54
Slide 54: Drug Resistant TB
• [Note: This slide has one animation to add emphasis. An infographic about Michigan will appear after you advance the slide (click) once.]
• Drug resistant TB is caused by M. tuberculosis organisms that are resistant to the drugs normally used to treat the disease. It develops when the antibiotics used to treat TB are misused or mismanaged. There are three main types of drug resistant TB [read through the types].
• In 2017 there were 847 cases of MDR TB in the US, and in 2018 Michigan had four people with MDR TB.
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Roles of the Local Health Department
55
Surveillance• Mandatory reporting TB disease to LHD• Monitoring drug susceptibility
Case management• Ensure health care accessibility and cost• Ensure completion of appropriate treatment
Contact Investigations• Start with closest contacts, give priority to children and immunosuppressed• Expand with infectivity (concentric circle model)
State and local health departments have the primary responsibility for preventing and controlling TB. However, TB is a complex disease and requires the collaborative
efforts of people and organizations throughout the public health sector.
Slide 55: Roles of the Local Health Department
• Your local health department is primarily responsible for TB case management and community surveillance of TB, including contact investigations.
• It is mandatory that you report all suspected and confirmed people with active TB disease to your local health department.
• State and local health departments have the primary responsibility for preventing and controlling TB. However, TB is a complex disease and requires the collaborative efforts of people and organizations throughout the public health sector.
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Questions
Helen [email protected]
517‐284‐4957
TB testingTST Workshop content
Kathryn WiltonMDHHS‐[email protected]
517‐285‐9625
Online Portal: registration, event creation, etc. Continuing education
Waivers, instructor and MRT applicationsRuler requests
56
Slide 56: Questions
• [Encourage questions from the audience]
• If you have other questions about the TB testing workshop, please contact the appropriate person at MDHHS.
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Evaluation
https://www.surveymonkey.com/r/TSTworkshop
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Slide 57: Evaluation
• Please type the following link into your browser or scan the QR code to take the workshop evaluation.
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