Fig. 2

Geographical distribution of the studies included in this review according to the regions of Brazil. Each black line indicates the number of studies with samples from the respective region of the country (they are not distributed on the map according to the state or municipality localization). Red lines indicate the number of studies with samples from South and Southeast regions. The blue lines indicate studies that used populations from more than two regions (South, Southeast and Northeast). *Only two study included samples from all regions of the country