UC Merced Undergraduate Research Journal

Tuberculosis (TB) remains a persistent communicable disease and an ongoing public health concern in California despite being preventable and treatable. Certain populations continue to experience a disproportionate burden of disease due to structural and social determinants of health, including poverty, housing instability, limited healthcare access, and barriers related to language and immigration status. This report examines TB trends and disparities across Santa Clara, Alameda, and Merced Counties using secondary epidemiological data and a key informant interview with a public health professional involved in TB prevention and control. The counties were selected to highlight differences between highly urbanized Bay Area regions and a Central Valley county with higher poverty levels and a mixed rural-urban population.

Comparative analysis of TB incidence rates shows that Alameda County (7.8 per 100,000) and Santa Clara County (7.4 per 100,000) reported higher TB rates in 2024 than Merced County (3.8 per 100,000), though Merced experiences structural barriers that may influence disease risk and access to care. Demographic and socioeconomic differences, including educational attainment, income levels, and healthcare access, provide important context for understanding these patterns. Findings from the key informant interview further highlight challenges related to continuity of care, treatment adherence, and barriers faced by uninsured populations and migrant agricultural workers. Overall, the analysis demonstrates that TB patterns vary across counties and underscores the importance of tailored, community-based strategies that address social determinants of health and improve early detection, linkage to care, and treatment completion.