Evaluation of HIV transmission clusters among natives and foreigners living in Italy

Fabeni, L.; Santoro, M. M.; Lorenzini, P.; Rusconi, S.; Gianotti, N.; Costantini, A.; Sarmati, L.; Antinori, A.; Ceccherini-Silberstein, F.; d'Arminio Monforte, A.; Saracino, A.; Girardi, E.; Castagna, A.; Castelli, F.; Cauda, R.; Di Perri, G.; Galli, M.; Iardino, R.; Ippolito, G.; Lazzarin, A.; Marchetti, G. C.; Rezza, G.; von Schloesser, F.; Viale, P.; Cozzi-Lepri, A.; Gori, A.; Lo Caputo, S.; Maggiolo, F.; Mussini, C.; Puoti, M.; Perno, C. F.; Bai, F.; Bandera, A.; Bonora, S.; Borderi, M.; Calcagno, A.; Capobianchi, M. R.; Cicalini, S.; Cingolani, A.; Cinque, P.; Di Biagio, A.; Gagliardini, R.; Guaraldi, G.; Lapadula, G.; Lichtner, M.; Lai, A.; Madeddu, G.; Merlini, E.; Nozza, S.; Piconi, S.; Pinnetti, C.; Quiros Roldan, E.; Rossotti, R.; Spagnuolo, V.; Svicher, V.; Taramasso, L.; Fanti, I.; Galli, L.; Rodano, A.; Macchia, M.; Tavelli, A.; Bove, A.; Camposeragna, A.; Errico, M.; Manfredini, M.; Perziano, A.; Calvino, V.; Carrara, S.; Di Caro, A.; Graziano, S.; Petroni, F.; Prota, G.; Truffa, S.; Giacometti, A.; Barocci, V.; Angarano, G.; Monno, L.; Milano, E.; Suardi, C.; Donati, V.; Verucchi, G.; Castelnuovo, F.; Minardi, C.; Menzaghi, B.; Abeli, C.; Chessa, L.; Pes, F.; Cacopardo, B.; Celesia, B.; Vecchiet, J.; Falasca, K.; Pan, A.; Lorenzotti, S.; Sighinolfi, L.; Segala, D.; Blanc, P.; Vichi, F.; Cassola, G.; Bassetti, M.; Alessandrini, A.; Bobbio, N.; Mazzarello, G.; Fondaco, L.; Bonfanti, P.; Molteni, C.; Chiodera, A.; Milini, P.; Nunnari, G.; Pellicano, G.; Rizzardini, G.; Cannizzo, E. S.; Moioli, M. C.; Piolini, R.; Bernacchia, D.; Poli, A.; Tincati, C.; Puzzolante, C.; Migliorino, C.; Sangiovanni, V.; Borgia, G.; Esposito, V.; Di Flumeri, G.; Gentile, I.; Rizzo, V.; Cattelan, A. M.; Marinello, S.; Cascio, A.; Trizzino, M.; Francisci, D.; Schiaroli, E.; Parruti, G.; Sozio, F.; Lazzaretti, C.; Corsini, R.; Cristaudo, A.; Vullo, V.; Acinapura, R.; Lamonica, S.; Capozzi, M.; Mondi, A.; Rivano Capparuccia, M.; Iaiani, G.; Latini, A.; Onnelli, G.; Plazzi, M. M.; de Girolamo, G.; Vergori, A.; Cecchetto, M.; Viviani, F.; de Vito, A.; Rossetti, B.; Montagnani, F.; Franco, A.; Fontana Del Vecchio, R.; Di Giuli, C.; Caramello, P.; Orofino, G. C.; Sciandra, M.; Londero, A.; Manfrin, V.; Battagin, G.; Starnini, G.; Ialungo, A.

doi:10.3390/v12080791

We aimed at evaluating the characteristics of HIV-1 molecular transmission clusters (MTCs) among natives and migrants living in Italy, diagnosed between 1998 and 2018. Phylogenetic analyses were performed on HIV-1 polymerase (pol) sequences to characterise subtypes and identify MTCs, divided into small (SMTCs, 2-3 sequences), medium (MMTCs, 4-9 sequences) and large (LMTCs, ≥10 sequences). Among 3499 drug-naïve individuals enrolled in the Italian Cohort Naive Antiretroviral (ICONA) cohort (2804 natives; 695 migrants), 726 (20.8%; 644 natives, 82 migrants) were involved in 228 MTCs (6 LMTCs, 36 MMTCs, 186 SMTCs). Migrants contributed 14.4% to SMTCs, 7.6% to MMTCs and 7.1% to LMTCs, respectively. HIV-1 non-B subtypes were found in 51 MTCs; noteworthy was that non-B infections involved in MTCs were more commonly found in natives (n = 47) than in migrants (n = 4). Factors such as Italian origin, being men who have sex with men (MSM), younger age, more recent diagnosis and a higher CD4 count were significantly associated with MTCs. Our findings show that HIV-1 clustering transmission among newly diagnosed individuals living in Italy is prevalently driven by natives, mainly MSM, with a more recent diagnosis and frequently infected with HIV-1 non-B subtypes. These results can contribute to monitoring of the HIV epidemic and guiding the public health response to prevent new HIV infections.