1. Department of Internal Medicine, School of Medicine of Ribeirão Preto; University of São Paulo; 14049-900 Ribeirão Preto SP Brazil
2. Program of Graduate Studies of Applied Microbiology and Immunology, School of Medicine of Ribeirão Preto; University of São Paulo; 14049-900 Ribeirão Preto SP Brazil
3. Virology Research Center, School of Medicine of Ribeirão Preto; University of São Paulo; 14049-900 Ribeirão Preto SP Brazil
4. Program of Graduate Studies in Biological Sciences, Biosciences Center; Federal University of Rio Grande do Norte; 59072-970 Natal Brazil