Transfusion-Transmitted Bacterial, Viral and Protozoal Infections

Blood transmitted infection is the commonest cause of death after blood transfusion. All patients on regular packed cell volume (PCV) or any blood component are at increased risk of transfusion transmitted infections. The etiological agents can be virus, bacteria or protozoa. These organisms can cause clinical sickness in recipient, can persist in him as carrier state or can cause asymptomatic infection in him. Every blood bank follows screening procedures to prevent such infections but the infective agents escape detection due to window period – a period where in the infective agent’s presence cannot be detected, though it is present in donor’s blood. Blood banks in developed countries are doing Nucleic Acid Amplification Testing (NAT) since 1999 to screen donated blood. The window period for testing for HIV, Hepatitis B and Hepatitis C has been significantly reduced with NAT. NAT can detect low levels of viral genetic material in blood.