title: Reply to Perez and Patel.
authors.affiliation: Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Switzerland.
authors.forename: Nadja
authors.initials: N
authors.lastname: Leimer
authors.affiliation: Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Switzerland.
authors.forename: Annelies S
authors.initials: AS
authors.lastname: Zinkernagel
mesh_terms: D006863:Hydrogen-Ion Concentration; D008247:Lysosomes