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What is Screening for following viral infections in blood donor is compulsory: and explain in detail?
Screening of all blood donations should be mandatory for the following infections and using the following markers:

HIV-1 and HIV-2: Screening for either a combination of HIV antigen-antibody or HIV antibodies.
Hepatitis B: Screening for hepatitis B surface antigen (HBsAg).
Hepatitis C: Screening for either a combination of HCV antigen-antibody or HCV antibodies.
Syphilis (Treponema pallidum): Screening for specific treponemal antibodies.