Hepatitis C Virus infections trends in Italy, 1996-2006.

BACKGROUND

The World Health Organization (WHO) estimates that about 180 million people, 3% of the world population, are infected with the hepatitis C virus (HCV). In Italy, the prevalence in the general population is reported to be greater than 5% and 9% among households of HCV-positive patients.

OBJECTIVES

The aim of this study was to estimate the trends of HCV infection in Italy in the period 1996-2006.

MATERIALS AND METHODS

The formula ln (rate) = b × years was applied for logarithmic transformation of the incidence rates to obtain time trends of HCV infection, using the join-point regression program software version 3.3.1. Linear graphs representing trends and the annual percentage change (APC) were considered for each joinpoint. Time changes are expressed as expected annual percentage change (EAPC) with the respective 95% confidence intervals (CIs); significance levels of time trends are also reported. The null hypothesis was tested using a maximum of 3 changes in slope with an overall significance level of 0.05 divided by the number of joinpoints in the final model.

RESULTS

Considering all age groups, the incidence rate decreased from 2.02 to 0.55 per 100,000. The join-point analysis showed a statistically significant decrease in the incidence rates of HCV infection. No join-points were found in any age groups. Our data show that the incidence rates of HCV infections have considerably decreased in each age group throughout the studied period (1996-2006).

CONCLUSIONS

This decreasing trend in HCV infections is, in part, attributable to behavioral and social changes. Improved hygiene, use of precautions in medical settings, blood screening, and sexual educational campaigns seem to have contributed to reduce the transmission of infection during the last 10 years.