1. Division of Pathology, Department of Stomatology, School of Dentistry, University of Sao Paulo, Sao Paulo, Brazil
2. Division of Dentistry, Instituto do Cancer do Estado de Sao Paulo Octavio Frias de Oliveira, Sao Paulo, Brazil
3. Laboratory of Virology, Institute of Tropical Medicine of Sao Paulo, University of Sao Paulo, Sao Paulo, Brazil