Thursday, August 25, 2016
Hepatitis B Risk From Transfusion
what are the risks of contracting HBV through blood transfusions in under developed countries? I am thinking of SE Asia, Thailand, Vietnam, etc... can I still get HBV from blood if I am vaccinated?
I don’t have any specific knowledge of how other countries screen their blood donors for infectious diseases, but the World Health Organization has reported that many countries do not carry out the recommended basic screening.
The Southeast Asian countries you mention have very high Hepatitis B virus (HBV) carrier rates, between 8 and 20%, so your question is a good one. It’s hard to predict whether or not a vaccinated person would catch HBV from a blood transfusion if the blood donor was a carrier of HBV, because there may be many factors involved. Particularly shortly after being infected, HBV carriers may have an especially high amount of HBV in their blood, so the risk to the transfusion recipient may be higher. Also, what if the immune system of the recipient of the blood transfusion has been weakened by an illness or medication?
In general, if you have previously been vaccinated and have had anti-HBs Ab positive with a level of >10mIU/mL drawn after the last dose of Hepatitis B vaccine, you should be protected. The CDC says that studies indicate that immunologic memory remains intact for at least 23 years and confers protection against clinical illness and chronic HBV infection, even though anti-HBs levels might become low or decline below detectable levels.
Unfortunately, some people are vaccine “nonresponders,” and may not develop protective immunity despite being vaccinated. Before you travel, you could find out if you have antibodies against HBV. You should ask your doctor about how to interpret your test results.
Lisa A Haglund, MD
Associate Professor of Clinical Medicine
College of Medicine
University of Cincinnati