What countries have high endemic rates of tuberculosis?

High TB Endemic Countries

Sub-Saharan Africa has the highest TB incidence rate globally at 356 new cases per 100,000 population per year, while most countries of the former Soviet Union exceed 100 new cases per 100,000 population per year. 1

Geographic Regions with Highest TB Burden

Sub-Saharan Africa

• Represents the region with the highest TB incidence rate worldwide at 356 cases per 100,000 population annually 1
• The worsening TB epidemic in Africa is driven by the HIV epidemic compounded by insufficient health infrastructure 1
• Specific high-burden countries include Somalia (406/100,000), South Africa, Nigeria, Ethiopia, and the Democratic Republic of the Congo 1, 2, 3

Former Soviet Union and Eastern Europe

• Most countries in this region have estimated incidence rates exceeding 100 new cases per 100,000 population per year 1
• The Baltic states and parts of Russia have particularly concerning rates, with >10% of new TB cases being multidrug-resistant 1
• Economic decline, increased poverty, social disruption, and sub-standard health services drive the epidemic in Eastern Europe 1

Countries Accounting for the Largest Global TB Burden

The "Big Eight" High-Burden Countries

Eight countries collectively account for approximately two-thirds of all global TB cases: 2, 3, 4

1. India (26% of global cases) - the single largest contributor 3, 4
2. Indonesia (8.5%) 3, 4
3. China (8.4%) 3, 4
4. Philippines (6.0%) 3, 4
5. Pakistan (5.7%) 3, 4
6. Nigeria (4.4%) 3, 4
7. Bangladesh (3.6%) 3, 4
8. South Africa (3.6%) 3, 4

Additional High-Burden Countries from U.S. Immigration Data

The 14 countries most frequently listed as origin countries for foreign-born persons with TB in the United States include: 1

• Mexico (33/100,000 - lowest of the group but highest absolute numbers to U.S.) 1
• Philippines, Vietnam, India, China (already listed above) 1
• Haiti, South Korea, Guatemala, Ecuador, Ethiopia, Peru, El Salvador, and Honduras 1
• These 14 countries accounted for 76% of TB cases among foreign-born persons in the United States during 1999-2002 1

Practical Screening Thresholds

WHO and International Guidelines

• Countries with TB incidence >100 cases per 100,000 population are generally considered high-risk populations for screening purposes 5
• The European Centre for Disease Prevention and Control recommends screening for migrants from countries with TB incidence >120 cases/100,000 5

Clinical Application

• State and local TB control programs should develop their own risk profiles based on: 1
  • WHO data on estimated TB incidence in countries of origin
  • Local epidemiologic and surveillance data
  • Qualitative information on refugee and immigrant movement patterns
  • Available resources for targeted control measures

Important Clinical Caveats

Drug Resistance Patterns

• Foreign-born persons from high-burden countries are more likely to harbor drug-resistant strains: 10.6% had primary isoniazid resistance compared to 4.6% in U.S.-born persons 1
• The Baltic states and parts of Russia have particularly high MDR-TB rates exceeding 10% of new cases 1

Temporal Risk Considerations

• Approximately 47% of foreign-born persons with TB receive their diagnosis within 5 years of arrival in destination countries 1
• TB rates are nearly four times higher among persons residing in the United States for fewer than 5 years compared to those with 5+ years of residence 1
• Recent guidelines designate immigrants from high-prevalence countries who have resided in the United States fewer than 5 years as being at highest risk 1

Emerging Trends

• The Philippines shows a concerning upward trend with average annual percentage change of 3.1% from 1990-2021, and is projected to reach 392.9 per 100,000 by 2030 2
• India and Indonesia are projected to achieve less than 20% of WHO targets by 2030 2