Abbreviations, Acronyms and Definitions
Active Tuberculosis: Tuberculosis is an infection with Mycobacterium tuberculosis. The infection can either be latent, where an individual does not have symptoms and cannot infect others, or progress to active disease, where an individual has symptoms and can spread the bacteria to others (see TB Disease).
AIDS: Acquired immunodeficiency syndrome.
DOT: Directly observed therapy. Healthcare personnel watch patients take their anti-tuberculosis medications to ensure adherence to therapy.
Extrapulmonary TB: A person with Mycobacterium tuberculosis infection outside of the lungs, the pleural space, and the larynx (voice box). A person with extrapulmonary disease can also have pulmonary TB (see below)
HIV: Human immunodeficiency virus, the virus that can lead to AIDS.
IDSS: IDSS stands for Illinois Disease Surveillance System. IDSS is a web-based application that establishes a secure and real-time communication link between hospitals, laboratories and other health care providers with state and local health department staff for the purposes of reporting and managing communicable disease information. All TB cases in suburban Cook County are reported to the Illinois Department of Public Health using IDSS.
INH: Abbreviation for isoniazid, an anti-TB medication.
MDR-TB: Multi drug resistant TB. MDR-TB is defined as TB resistant to isoniazid and rifampin, the two most important first line anti-tuberculosis medications.
National Tuberculosis Indicators Project (NTIP): Monitoring system for tracking the progress of U.S. tuberculosis (TB) control programs toward achieving the national TB program objectives.
Pulmonary TB: A person with Mycobacterium tuberculosis infection of the lungs, pleural space or the larynx (voice box). A person with pulmonary TB can also have extrapulmonary TB.
RIF: Abbreviation for rifampin, an anti-TB medication.
SA: Self-administered therapy. Patients are NOT watched by healthcare personnel while taking their anti-tuberculosis medications.
TB: Tuberculosis.
TB Disease: A person with TB infection who is contagious to others; a person with TB disease can have pulmonary TB, extrapulmonary TB, or both.
XDR-TB: Extensively drug resistant TB. XDR-TB is defined as MDR-TB plus TB that is resistant to any fluoroquinolone plus resistance to one of the three injectable drugs (i.e., amikacin, kanamycin, or capreomycin).
Executive Summary
In suburban Cook County, there were 65 new cases of active TB in 2022. Over the past 23 years, TB rates have fallen 54% from 5.7 per 100,000 in 2000 to 2.6 cases per 100,000 in 2022. However, cases have stabilized since 2020. Nationally, state-wide, and in Chicago, cases have increased since 2020. The municipalities with the highest number of cases were Skokie, Mount Prospect, and Cicero.
The majority of cases (85%) were foreign-born, with 3 countries accounting for 67% of the foreign-born cases: India (27%), Mexico (25%), and The Philippines (15%). Individuals infected with Mycobacterium tuberculosis can incubate the bacteria for a long time, not realizing that they are infected until they start to feel sick years later. Among foreign-born persons diagnosed with TB, 85% arrived in the US 5 or more years prior to receiving a diagnosis of TB disease.
Only 10 US-born TB cases were reported in 2022, but there were notable differences in race/ethnicity depending on whether cases were US- or foreign-born. The majority (60%) of US-born cases identified as Black, not Hispanic. This tracks with national trends, however, only 15.7% of suburban Cook County residents identify as non-Hispanic Black.
More than 7 out of 10 TB diagnoses in 2022 were 45 years or older, with the largest age group being 65 years and older. There were more male (n=36; 55%) cases than female (n=29; 45%).
In 2022, 75% of cases were tested for drug resistance: 5 cases of MDR-TB and no cases of XDR-TB were identified. 100% of patients diagnosed in 2022 were tested for HIV.
Pulmonary disease (either exclusively or in combination with extrapulmonary disease) continued to represent the majority (68%) of cases in suburban Cook. In 2022, 91% of patients with pulmonary TB received DOT, the gold standard for treatment. CCDPH has maintained a high level of DOT enrollment for several years. The NTIP goal is to have 95% of eligible residents complete therapy within the span of 12 months; last year (2021) 92.3% of cases in suburban Cook County completed therapy within this time span and 94.2% completed therapy overall.
TB Trends By Select Jurisdictions
Figure 1. Trends in TB Diagnoses by Select Public Health Jurisdictions, 2000-2022
- The number of TB diagnoses had declined significantly from 2000-2022 in all selected geographies, but has increased since 2020.
- In suburban Cook County, the TB rate dropped 54% from 5.7 in 2000 to 2.6 in 2022.
TB in Suburban Cook County
Map 1. Average (3-Year) TB Rate per 100,000 Population, Suburban Cook County, 2022
Demographics
Figure 2. Percent of TB Cases by Sex, Suburban Cook County, 2022
- There were more males (n=36; 55%) than females (n=29; 45%) diagnosed with TB in 2022.
Figure 3. Percent of TB Cases by Select Age Groups, Suburban Cook County, 2022
- More than 7 out of 10 suburban Cook TB cases in 2022 were 45 years or older.
Figure 4. Percent of TB Cases by Place of Birth and Race/Ethnicity, Suburban Cook County, 2022
- There were notable differences in the race/ethnicity distribution depending on whether cases were US- or foreign-born.
Country of Origin
Figure 5. Percent of TB Cases by Place of Birth, Suburban Cook County, 2022
- The vast majority of TB diagnoses in 2022 (85%) were in those born overseas.
Figure 6. Percent of TB Cases by Select Countries of Origin and Tenure in the US, Suburban Cook County, 2022
- More than 8 in 10 foreign-born cases diagnosed with TB in 2022 have been living in the US for 5 or more years.
Map 2. Countries of Origin for Suburban Cook County Residents Diagnosed with TB, 2022
Foreign-born people diagnosed with TB in 2022 came from 16 different countries.
67% of TB cases diagnosed in 2022 came from India, Mexico, and The Philippines.
Drug Resistance
Figure 7. Drug Resistance in Foreign-born TB Cases in Suburban Cook County, 2022
Figure 8. Drug Resistance in US-born TB Cases in Suburban Cook County, 2022
Pathology
Figure 9. Pulmonary TB Labs, Suburban Cook County, 2022
Includes cases with exclusively pulmonary TB as well as those who have both pulmonary and extrapulmonary TB.
Figure 10. Extrapulmonary TB Labs, Suburban Cook County, 2022
Includes cases with exclusively extrapulmonary TB as well as those who have both pulmonary and extrapulmonary TB.
Figure 11. TB Cases Coinfected with HIV, Suburban Cook County, 2022
Treatment
Figure 12. Trends in Administration of Antituberculosis Therapy in Pulmonary Cases, Suburban Cook County, 2017-2022
*Includes those alive at the time of diagnosis who started therapy and for whom therapy completion within 1 year was indicated.
- For pulmonary cases diagnosed in 2022, 97.3% received some form of directly observed therapy.
Figure 13. Trends in Treatment Completion of Antituberculosis Therapy in Pulmonary Cases, Suburban Cook County, 2017-2022
*Includes those alive at the time of diagnosis who started therapy and for whom therapy completion within 1 year was indicated.
The proportion of eligible 2021 TB cases completing therapy in 12 months or fewer in 2021 was 92.3%. This was slightly less than the National TB Indicator Project goal of 95%.
The proportion of eligible 2021 TB cases ever completing therapy was 94.2%.