12 doctors weighed in:
How does donated blood that has some kind of infection sometimes pass through all the screening tests?
12 doctors weighed in

Dr. Devon Webster
Internal Medicine - Oncology
7 doctors agree
In brief: Timing
If the blood donor was recently infected with HIV or another virus like hepatitis, it may not show up in the blood test.
That's why there are so many questions a blood donor must answer before donating, to hopefully rule out any chance for a recent infection.

In brief: Timing
If the blood donor was recently infected with HIV or another virus like hepatitis, it may not show up in the blood test.
That's why there are so many questions a blood donor must answer before donating, to hopefully rule out any chance for a recent infection.
Dr. Devon Webster
Dr. Devon Webster
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2 comments
Dr. Michael Thompson
I agree with Dr. Webster. That is one reason that blood is a donation, not paid for. I would also note that the blood system isn't perfect, but has improved and gotten safer. With increased regulatory and financial constraints on the use of erythropoietin (Epo), we may be using more blood (RBCs) than in the past.
Dr. Barry Rosen
Thankfully, the screening methods are ver effective: the risk of HIV or Hepatitis C from a blood transfusion is about 1 in 2 million; the risk of Hepatitis B is about 1 in 200,0000.
Dr. Kenneth Cheng
Family Medicine
5 doctors agree
In brief: Depends on test
Donated blood goes through fairly extensive testing, but is not tested for every possible infection known to man.
Tests that are currently done include hiv, hepatitis a, hepatitis b, hepatitis c and liver function. Remember also that no test is ever 100% accurate 100% of the time; false negatives do occur.

In brief: Depends on test
Donated blood goes through fairly extensive testing, but is not tested for every possible infection known to man.
Tests that are currently done include hiv, hepatitis a, hepatitis b, hepatitis c and liver function. Remember also that no test is ever 100% accurate 100% of the time; false negatives do occur.
Dr. Kenneth Cheng
Dr. Kenneth Cheng
Thank
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