1 Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Bloomsbury, London, UK.
2 Faculty of Health Sciences, Universidad Anáhuac México, Huixquilucan, Mexico State, Mexico.
3 Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Bloomsbury, London, UK, Global Health Chapter, Mexican Society of Public Health, Miguel Hidalgo, Mexico City, Mexico.