Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started
My Medicine

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

HIV & AIDS Health Center

Font Size

Unclear HIV Test Should Not Necessarily Bar Blood Donors

WebMD Health News

June 14, 2001 (Washington) -- Blood donors who have been banned from donating because of unclear tests for HIV or the hepatitis C virus should be allowed to donate again provided they undergo follow-up tests that confirm they are not infected with either of these viruses, a panel of experts convened by the FDA said on Thursday.

It is believed that these rare types of donors are not actually infected with one of the viruses. This is because even though they have tested positive for the viruses on tests designed to detect antibodies produced by the body in response to the virus, they have tested negative on more specific tests designed to detect the virus itself.

"These people are probably not infected" with the HIV or hepatitis C virus, but for whatever reason the blood tests don't reflect this, the FDA's deputy director of the division of emerging and transfusion transmitted diseases, Paul Mied, PhD, tells WebMD. Sometimes it is because the blood sample has become contaminated and in other cases the tests may simply have given false readings, he says.

The FDA was concerned about how to handle such false positive donors because current guidelines were developed before the more specific tests, which detect the RNA or genetic material of the virus, were available, Mied tells WebMD.

The ultimate decision as to whether to allow falsely positive donors to begin donating again rests with the blood banks, Mied says. But the blood banks must adhere to criteria established by the FDA.

The FDA's blood products advisory committee recommends that in the case of a false positive test for the hepatitis C virus, a second test should be done after six months because it may take this long for the person to develop detectable antibodies to the virus. In the case of HIV, the second test should be done after 56 days. Waiting until the person should have developed antibodies will help to rule out false positives.

The FDA is not bound by the recommendations of its advisory committees, but it usually follows their advice. Both the American Red Cross and the American Association of Blood Banks agreed with the committee's recommendation.

Today on WebMD

How much do you know?
contemplative man
What to do now.
Should you be tested?
HIV under microscope
What does it mean?
HIV AIDS Screening
man opening condom wrapper
HIV AIDS Treatment
Discrimination Stigma
Treatment Side Effects
grilled chicken and vegetables
obese man standing on scale
cold sore