1. Discipline of Medical Informatics, School of Medicine, The University of São Paulo, and LIM 01/HCFMUSP, Av.Dr.Arnaldo 455, São Paulo, 01246-903, S.P., Brazil
2. Discipline of Medical Informatics, School of Medicine, The University of São Paulo, Brazil
3. Discipline of Medical Informatics, School of Medicine, The University of São Paulo and Discipline of Infectious Diseases, Escola Paulista de Medicina, Brazil
4. Institute of Physics, The University of São Paulo, Brazil