1990-8644 1990-8644 S1990-86442021000600462 Ecuador 00 12 2021 00 12 2021 17 83 462 468

2009 47 3 3 2019 47 3 3 217-22 2018 3 2 2 2019 26 2018 17 55 55 1418-26 2013 24 1 1 73-83 2020 32 344-6 2020 23 3 3 327-31 2014 25 3 3 318-32 2018 2018 21-48 2016 1 1 1 32-7 World Health Organization 1994 2020