Deprivation, immigration and tuberculosis incidence in Naples, 1996-2000

Most of the tuberculosis cases in Campania occur in Naples, the biggest city in the South of Italy with the highest unemployment and immigration rates. However, the occurrence of tuberculosis differs between the different neighbourhoods and it is not known whether these differences are associated with poverty or with immigration. We describe tuberculosis incidence and its association with socio-economic status and immigration in the city of Naples during the period 1996-2000. The basic design was an ecological study, correlating the incidence of tuberculosis which was calculated on the basis of notified tuberculosis cases to census data on immigration and socio-economic deprivation per neighbourhood. Immigrants had a high risk for tuberculosis (RR=34 for Africans) but the incidence of TB varied largely by districts and seemed independent of immigration. All socioeconomic factors increased the incidence of TB significantly. In a multivariate Poisson regression analysis only the rate of unemployment (p=0.02) and the population density (p=0.002) remained independently associated with tuberculosis incidence. In this study we showed that deprivation explained differences in tuberculosis incidence in Naples to a greater extent than immigration.