# Trends in Tuberculosis Incidence and Mortality in South Africa and Bulgaria (2000–2023): The Impact of Income, Poverty, Unemployment, and Universal Health Coverage

## TL;DR

This paper compares TB trends in South Africa and Bulgaria from 2000 to 2023, showing how socioeconomic factors like unemployment and GDP influence TB incidence differently in each country.

## Contribution

The study provides a comparative analysis of TB trends in two distinct countries, linking them to socioeconomic and health coverage factors in a novel cross-national context.

## Key findings

- TB incidence declined by 44% in South Africa and 69% in Bulgaria from 2000 to 2023.
- Unemployment strongly correlated with TB incidence in both countries (r = 0.805 in South Africa and r = 0.723 in Bulgaria).
- In Bulgaria, TB incidence was strongly negatively associated with GDP per capita (r = −0.910), unlike in South Africa.

## Abstract

Background: Tuberculosis (TB) remains a major global public health challenge, with substantial variation across countries. South Africa has one of the highest TB incidence and mortality rates globally, while Bulgaria, a low-incidence country, faces a persistent TB burden among vulnerable populations. Objectives: To compare national trends in TB incidence and mortality in South Africa and Bulgaria from 2000 to 2023 and explore associations with selected socioeconomic indicators and health system coverage. Methods: An ecological, descriptive, analytical study used national-level data from the WHO, World Bank, and official statistics. TB trends were analyzed alongside income, poverty, unemployment, and Universal Health Coverage indicators. Time series measures and Pearson correlation were used descriptively to summarize co-variation over time. Results: Between 2000 and 2023, TB incidence declined by approximately 44% in the Republic of South Africa and 69% in Bulgaria. In both countries, TB incidence co-varied strongly with unemployment (RSA: r = 0.805; BG: r = 0.723). In Bulgaria, TB incidence was also strongly negatively associated with GDP per capita (r = −0.910), whereas no significant association with GDP was observed in South Africa. These findings indicate that TB trends co-varied more closely with labour market conditions in both contexts, while broader economic growth co-occurred with declining TB incidence only in Bulgaria. Conclusions: TB trends co-occurred with changes in socioeconomic conditions and health system coverage, with differing patterns across contexts. Findings highlight the relevance of equity-oriented, context-specific TB control strategies integrated with social and economic policies.