Low death rate due CV in mexico might be due the fact that CHLOROQUINE is already available as a basic drug in the mexican health sistem.

http://www.csg.gob.mx/descargas/pdf/priorizacion/cuadro-basico/med/catalogo/2016/EDICION_2016_MEDICAMENTOS.pdf

https://mexiconewsdaily.com/news/coronavirus/mexico-records-its-first-coronavirus-death/