1. Department of Therapeutic Research and Medicine Evaluation, Istituto Superiore di Sanità, Rome, Italy.
2. General Pediatric and Infectious Disease Unit, Internal Care Department, Bambino Gesù Children's Hospital, Rome, Italy.
3. Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy.
4. San Raffaele Institute Sulmona, L'Aquila, Italy.