Received: 5 December 2019
Accepted: 13 May 2020
First Online: 29 May 2020
Ethics approval and consent to participate
: The research ethics committees of all six centers approved this study (Federal University of Minas Gerais - UFMG: 186/06; São Paulo University - USP: 669/06; Federal University of Rio Grande do Sul - UFRGS: 194/061; Federal University of Espírito Santo - UFES: 041/06; Federal University of Bahia - UFBA: 027/06; Oswaldo Cruz Foundation - FIOCRUZ: 343/06), and all participants freely signed a declaration of informed consent.
: Not applicable.
: The authors declare that they have no competing interests