1. Laboratory of Molecular BiologyBlood Center of Ribeirão Preto, Faculty of Medicine of Ribeirão Preto University of São Paulo, Ribeirão Preto São Paulo Brazil
2. Department of Internal Medicine, Faculty of Medicine of Ribeirão PretoUniversity of São PauloRibeirão Preto São Paulo Brazil
3. Department of Social Medicine, Faculty of Medicine of Ribeirão PretoUniversity of São PauloRibeirão Preto São Paulo Brazil
4. Butantan InstituteSão Paulo Brazil
5. Institute of VirologyUniversity of Bonn Medical CentreBonn Germany