Impact of immigration on burden of tuberculosis in Umbria: a low-incidence Italian region with high immigrants rates.

INTRODUCTION: In Italy, Tubercolosis (TB) has increasingly become a disease for specific population subgroups such as immigrants. The objective of this paper is to describe the trend in TB incidence from 1999 to 2008 in Umbria: a low-incidence Italian region with high immigrants rates.

METHODS: Data were obtained from the Regional Information System for Infectious Diseases. Using a linear regressions model we estimated trends for number of cases and incidence rates; with a logistic regression model we estimated the effect of a set of covariates on the probability of being affected by TB.

RESULT: 590 TB cases were reported of whom 254 (43%) were foreign. In 2008 39.7 new cases per 100.000 were registered among foreign-born subjects. TB incidence among Italians was 3.8/100.000 Italians. But a linear regression analysis showed a statistically significant decreasing trend in the notification rate among foreign-born people (coef: -7.32, r2:0.57, p < 0.05). The probability to be affected by extra-pulmonary is significantly larger in foreign patients (OR = 0.72, CI = 0.48-1.07). Foreign unskilled workers report a higher probability to be affected by TB (OR = 19.05, CI = 6.01-60.4).

DISCUSSION: Increasing immigration rates may affect TB epidemiology. The analysis of incidence trends is an important toolfor monitoring tuberculosis disease control and to identify specific sub-group at risk.