title: Reply to letter to the editor: "JC viremia and multiple sclerosis" by Focosiet al.
authors.affiliation: Department of Biomedical Sciences and Technologies, University of Milan, Milan, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Delbue
authors.affiliation: Laboratory of Molecular Medicine and Biotechnology, Multiple Sclerosis Division, Don C. Gnocchi Foundation, ONLUS, IRCCS, Milan, Italy.
authors.forename: Franca Rosa
authors.initials: FR
authors.lastname: Guerini
authors.affiliation: Laboratory of Molecular Medicine and Biotechnology, Multiple Sclerosis Division, Don C. Gnocchi Foundation, ONLUS, IRCCS, Milan, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Mancuso
authors.affiliation: Neurology Department, Multiple Sclerosis Division, Don C. Gnocchi Foundation, ONLUS, IRCCS, Milan, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Caputo
authors.affiliation: Laboratory of Molecular Medicine and Biotechnology, Multiple Sclerosis Division, Don C. Gnocchi Foundation, ONLUS, IRCCS, Milan, Italy.
authors.forename: Romina
authors.initials: R
authors.lastname: Mazziotti
authors.affiliation: Laboratory of Molecular Medicine and Biotechnology, Multiple Sclerosis Division, Don C. Gnocchi Foundation, ONLUS, IRCCS, Milan, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Saresella
authors.affiliation: Department of Biomedical Sciences and Technologies, University of Milan, Milan, Italy ; Center for Translational Research, Saint Joseph Hospital, Milan, Italy.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Ferrante