High HIV heterogeneity in immigrants resident in Italy

Project Title:Virological and immunological studies on the dynamics of HIV, HBV and HCV genetic forms circulating in the population of resident immigrants in Italy

Duration of the project: No funds, no duration limits


Main Topic

The study is an extension of previously funded projects.

According to the European Centre for Disease, Prevention and Control (ECDC), migrants in the European Union/European Economic Area (EU/EEA) have a higher risk of HIV infection and related co-infections, such as HBV, HCV and tuberculosis (TB). In Italy, the Italian Institute of Statistics estimates indicate that the number of immigrants resident in Italy has been steadily increasing during the past 8 years and, by the beginning of 2018, more than 5 million foreign individuals were living in Italy. Consequently, the proportion of immigrants with new diagnoses of HIV infection has raised from 11% in 1992 to 34.3% in 2017. Concerning co-infections, the relative proportion of immigrants with chronic HBV infection in Italy has been estimated to be 20%, whereas the relative proportion of HCV infected immigrants is small.

HIV, HBV and HCV viruses are characterized by a broad genetic and antigenic variability. Such a variability is responsible of the extreme diversification of virus strains into genetic forms that can also recombine. This results in the presence of a wide array of genotypes and recombinant forms for all the three viruses. The genetic forms of these viruses have a defined geographic distribution that, however, is dynamically changing due to migrations, business travelling and military missions. These genetic forms can show a different ability to escape the host immune response, determine a different progression rate of the disease, show a different sensitivity to drugs have an impact on diagnosis and monitoring. In addition, each form can generate variants that are able to resist to specific drugs. Hence, the introduction of new genetic forms of these viruses into a population where these forms do not circulate can be a major public health problem.

Since immigrants often come from countries where different genetic forms of HIV, HBV and HCV are present, it is important to periodically carry out surveillance studies targeted on one side at evaluating the presence and the dynamics of the genetic forms of these viruses in the migrant community in Italy and, on the other side, at putting in place policies and interventions aimed at assuring access of immigrants to public health facilities. In fact, immigrants are frequently overrepresented among people living in poverty and are at high risk of social exclusion, which contributes to worsening their general health status and eroding any health advantages. In addition, a reduced access to public health facilities increase the risk of missing diagnoses of HIV, HBV and HCV infections, or, for those already under treatment, to select variants of these viruses that are resistant to treatment due to low patient adherence and scarce monitoring  of the therapy.



The project is therefore aimed at:

  1. Investigating the presence and the frequency of HIV, HBV and HCV genetic forms in the population of resident immigrants in Italy.
  2. Performing information to the immigrants on the transmission mechanisms of HIV, HBV and HCV and on behaviors to avoid transmission of these viruses and informing of their rights to have free access to the Italian public health system


Type of study

Taking advantage of a collaboration with clinical centers of 12 cities uniformly spread on the Italian territory, we collect plasma and cell samples from HIV infected resident immigrants attending these centers. During collection of samples, the immigrant is informed on the mechanisms of transmission of HIV, HBV and HCV, on the behaviors to prevent infection and on the available cures in case of infection.

At the National Center for HIV/AIDS research collected samples will be used for:

  • Testing for the presence of HBV and HCV markers.
  • Evaluating the presence of the HIV genetic forms by phylogenetic analysis of HIV sequences obtained either from plasma or cells
  • Evaluating the presence of the HBV and HCV genetic forms in those individuals who resulted to be HBV- and/or HCV-infected, by phylogenetic analysis of sequences from these viruses obtained from plasma.
  • Investigating for the presence of HIV and/or HBV and/or HCV variants that are resistant to therapy.


Expected results

At the moment, we have collected samples from over 500 HIV-infected immigrants, who have been informed on the risks of transmission of HIV, HBV and HCV and on how to prevent transmission and to cure for the infection. Almost 200 individuals have been characterized for the infecting HIV genetic forms, showing the presence of a high number of HIV clades and recombinant forms that are not common or even not present in the Italian autochthonous population.


Responsible of the project: Stefano Buttò (stefano.butto@iss.it)

Department/Center: Centro Nazionale per la Ricerca su HIV/AIDS