Anemia and the hemoglobin phenotype have an effect on O2 transport in the blood during malaria infection. Infected red blood cells transport O2 in a fraction of how uninfected cells do (122). Raman spectral changes in Plasmodium vivax-infected blood samples indicate a decrease in oxygen affinity(123). Intracellular hemoglobin's oxygen dissociation curve shifts to the right(123). The Bohr effect is a phenomenon that occurs when the concentration of CO2 in the blood decreases, lowering the intracellular pH and lowering the oxygen affinity of hemoglobin in red blood cells. The experiment found there is no significant difference in the oxygen affinity of erythrocyte hemolysates containing Hb-S and Hb-A following potassium phosphate buffer dialysis(124). The oxygen affinity of homozygous Hb-C and Hb-E carriers appears to be comparable to that of standard blood samples and erythrocyte lysates. When Hb-D with an abnormal chain is compared to a fraction of Hb-A separated, the Bohr effect remains unchanged. Hb-purified using CM-cellulose or DEAE-cellulose chromatography has a significantly higher affinity for molecular oxygen than normal Hb-A. The Bohr effect and the heme-heme interaction are identical. Patients with HbE-thalassemia can adapt to anemia by lowering their red blood cells' oxygen affinity. The presence of a high concentration of 2,3-BPG reduces the oxygen affinity to compensate for the high affinity of HbF. Heterozygosity hemoglobin is partially protective against Plasmodium falciparum. It facilitates the clearance of infected red blood cells by host immune effectors such as macrophages(125). Then, patients are less likely to develop potentially fatal cerebral malaria or severe anemia(125). Of course, other factors such as the initial infection dose, nutrition, co-infection, and genetics can be considered(126). The interaction between erythropoietin and hemoglobin levels does not appear to be directly related to the P50 value in these cases(127). When the SARS-COV-2 virus infects red blood cells or ORF3a invades red blood cells, a similar Bohr effect or anemia occurs as well.