Two biallelic markers; rs17860508 (designated as IL12Bpro): a complex promoter insertion/deletion polymorphism -/G/GC/TTAGA/TTAGAG situated at −2703 bp upstream of the transcription initiation site and rs3212227 (designated as IL12B+1188): an A to C substitution in the 3′UTR region at +1188 position of IL12B gene were selected to examine their probable association with the blood infection intensity in two hundred and ninety three patients exhibiting Plasmodium falciparum mild malaria from Eastern India. Here, IL12B is linked to infection.