A total of 3,132 immigrants from low- and middle-income countries were involved in a cross-sectional observational study to screen for infectious diseases among immigrants attending public primary health care (PHC) centers. The study was conducted to clarify the degree of demographic differences and risk predictors of these diseases.


Demographic and clinical variables, screening for infectious diseases [hepatitis B and C, human immunodeficiency virus infection, syphilis, and tuberculosis (TB)], and analytical data (anemia, hematuria, and liver function) were recorded from immigrants attending a public PHC unit in Barcelona.


Global hepatitis B, including chronic and previous, reached 18.1%; Morocco as the country of origin [odds ratio (OR) 2.1, 95% confidence interval (CI) 1.07–4.14] and gastrointestinal symptoms (OR 1.9, CI 1.18–3.02) were risk factors. Hepatitis C prevalence was 3.3% with elevated hepatic transaminase levels as a risk factor (OR 26.1, CI 8.68–78.37). Positive syphilis was 3.1%; latent and active TB rates were 28.1 and 5.8%, respectively. Concerning TB, we found remarkable differences both among WHO regions of origin (the Eastern Mediterranean region showed the highest rate of active TB, 8%) and the three categories of years of residence in Spain (6.5% for <1 year, 12.8% for 1–5 years, and 10% for >5 years).


The data allowed recommendation of a minimal screening of TB in immigrants from low-income countries regardless of the years of residence in Spain, hepatitis C in patients with altered transaminase levels, and hepatitis B in patients with gastrointestinal symptoms and/or from Morocco.