USPSTF High-Risk Countries for TB Screening
The USPSTF recommends screening persons born in or who are former residents of countries with TB incidence ≥20 cases per 100,000 population. 1
Defining High-Risk Countries
The USPSTF uses a quantitative threshold rather than a specific country list:
- Countries with TB incidence ≥20 cases per 100,000 population are considered high-risk for latent TB infection screening purposes 1
- This approach allows for dynamic updating as global TB epidemiology changes, rather than relying on static country lists 1
Most Commonly Affected Countries in U.S. TB Cases
While the USPSTF uses the incidence threshold above, epidemiologic data identifies the 14 countries most frequently listed as origin for foreign-born TB cases in the United States (accounting for 76% of foreign-born TB cases during 1999-2002): 2
- Mexico (33/100,000 incidence)
- Philippines
- Vietnam
- India
- China
- Haiti
- South Korea
- Somalia (406/100,000 incidence - highest among this group)
- Guatemala
- Ecuador
- Ethiopia
- Peru
- El Salvador
- Honduras
The incidence rates in these countries ranged from 33/100,000 (Mexico) to 406/100,000 (Somalia) in 2002 data. 2
Critical Screening Considerations
Time Since Arrival Does Not Eliminate Risk
- Screen foreign-born persons from high-incidence countries regardless of time since U.S. arrival 1
- Foreign-born persons diagnosed ≥10 years after U.S. arrival are more likely to have immunocompromising conditions or reside in long-term care facilities 1
- The risk of TB in early years after arrival approximates that of the country of birth, then gradually declines over time 2
Local Epidemiologic Variation
- Country of origin for foreign-born TB cases varies substantially between states and localities 2
- State and local TB control programs should develop their own risk profiles using WHO incidence data, local surveillance data, and refugee/immigrant movement patterns 2
Common Pitfalls
Avoid limiting screening to only recent arrivals (<5 years) - while immigrants from high-prevalence countries who have resided in the U.S. fewer than 5 years are designated as particularly high-risk 2, screening should continue beyond this timeframe given that increasing numbers of TB cases occur ≥10 years after arrival 1
Do not rely solely on historical country lists - use current WHO TB incidence data (≥20 cases per 100,000) as the operational definition, as global TB epidemiology evolves 1