[1] Marienkrankenhaus Hamburg, Neurol Klin, D-22087 Hamburg, Germany
[2] Univ Manchester, Div Virol, Manchester, Lancs, England
[3] Univ Gottingen, Neurol Klin, D-3400 Gottingen, Germany
[4] Deutsch Primatenzentrum, Abt Virol & Immunol, Gottingen, Germany
[5] Div Virus Reference, London, England
[6] Univ Milan, Osped San Raffaele, I-20127 Milan, Italy
[7] Acad Hosp Utrecht, Utrecht, Netherlands
[8] Swedish Inst Infect Dis Control, Stockholm, Sweden
[9] Univ Rome La Sapienza, Rome, Italy
[10] Karolinska Inst, Clin Virol, Stockholm, Sweden