1. Advanced Public Health Laboratory, Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Salvador, Bahia 40295-001, Brazil; Bahia School of Medicine and Public Health/Foundation for Development of Science, Salvador, Bahia 40290-000, Brazil and Federal University of Rio de Janeiro, Rio de Janeiro 27941-590, Brazil
2. Advanced Public Health Laboratory, Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Salvador, Bahia 40295-001, Brazil and Bahia School of Medicine and Public Health/Foundation for Development of Science, Salvador, Bahia 40290-000, Brazil
3. Rega Institute, Catholic University of Leuven, B-3000 Leuven, Belgium
4. Blood Center of Ribeirão Preto, São Paulo 14051-140, Brazil
5. IOC, Oswaldo Cruz Foundation/Rio de Janeiro 21045-400, Brazil
6. CN-DST/AIDS, Brazilian Ministry of Health, Brasilia 70750-543, Brazil