1. Department of Pathology, Institut de Pathologie et de Génétique, 25 Avenue Georges Lemaître, 6041 Gosselies, Belgium
2. Department of Pathology, Institut Jules Bordet and C.H.U. Saint-Pierre, 1 rue Héger-Bordet, 1000 Brussels, Belgium
3. Department of Otorhinolaryngology, C.H.U. Saint-Pierre, 322 rue Haute, 1000 Brussels, Belgium
4. Department of Infectious Diseases, C.H.U. Saint-Pierre, 322 rue Haute, 1000 Brussels, Belgium