1. Microbiology and Virology Unit, University Hospital Città della Salute e della Scienza di Torino , Turin , 10126 , Italy
2. Microbiology and Virology Unit, Amedeo di Savoia Hospital , Turin , 10149 , Italy
3. Ophthalmology Unit, Humanitas Gradenigo Hospital , Turin , 10153 , Italy
4. Ophthalmic Unit, Hospital San Biagio , Domodossola , 28845 , Italy
5. Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, Via V. De Sanctis, s.n.c. , Campobasso 86100 , Italy