##antigenic drift of ''Plasmodium''
#Relapse
*Duffy antigen on human RBC
**''P. vivax'' recognizes and utilizes as ligand Duffy antigen on human RBC surface
***Duffy-binding protein (DBP) in ''P. vivax''
**Genetically sub-Saharan people highly lack Duffy antigen, which consists the reason why ''P. vivax'' is not endemic in sub-Sahara
==疫学==