TNF and Plasmodium vivax malaria: Six TNF alleles polymorphism (TNF P-A, TNF P-B, TNF P-C, TNF P-D, TNF P-E, TNF P-F) based on five SNPs of biallelic polymorphism sites (-238, -308, -857, -863, -1031) in patients with severe (SM), uncomplicated falciparum (UM) and vivax malaria (VM) cases when data were combined for the three ethnic groups