Blood transfusion is a vitally important practice for emergency and sustaining health care administration. However blood donation incurs risk of infectious disease transmission that is not insignificant. Increased risks to hepatitis B, hepatitis C, HIV and other microbial infections is measurable. It is estimated that up to 10% of worldwide HIV infections is due to transfusion of contaminated blood and blood products. Effective screening methods for blood donors is vital is order to avoid transmission of disease. Laboratory methods for screening include enzyme immuno assays, chemiluminescent immuno assays, nucleic acid amplification assays, and particle agglutination assays. Incidents have been reported where donors not identified as HIV positive at time of donation but with high risk activity did indeed transmit HIV to blood product recipients. Hemolytic transfusion reactions are also a source of transfusion fatalities. The microbes Babesia microti and Escherichia coli have been associated with fatal transfusion outcome from recipients receiving red blood cells and pooled platelets, respectively. Other emerging pathogens in blood banks include hepatitis E, erythrovirus B19, and plasmodium. Previous studies have shown that Babesia microti and Escherichia coli accounts for 31%and 20%of transfusion fatalities that are due to microbial infection. Studies have revealed that donors having same sex activity entail additional risks of disease transmission which includes HIV, hepatitis A, hepatitis B, hepatitis C, and other infectious diseases. A small titer of Creutzfeldt-Jakob prion is still able to present a disease risk in blood transfusion. Calls for elevated blood screening methodologies in Caribbean nations to curtail prolific hepatitis C virus transmission by blood donation has been determined to be vital. Other disease conditions occurring by blood transfusion are discussed.