Hep C Window Period

How accurate is an antibody test for Hep C 16 weeks (4 months) post exposure?  Some say 3 months and others say 6.  The 6 month recommendation seems a bit outdated (kinda like how people say you need to test 6 months after an exposure to HIV) but I'm not sure.  Any input?

[Marcia2202]

Hope this explains it! Marcia


Antibody test

The initial screening test for hepatitis C is a blood test which checks for antibodies. The human body produces antibodies in response to the virus.
The antibody test looks for these specific antibodies, not for the virus itself, to work out if you have been exposed to the hepatitis C virus. It may take up to three months for antibodies to appear in your blood following infection (although it is usually positive by 6 weeks). This is known as the ‘window period’. During this time antibody testing may not provide an accurate result.

A negative antibody test result usually means that a person has not been infected with the virus. However, the blood sample may have been taken in the window period before antibodies can be detected.

A positive antibody test result means antibodies were found, which is proof that the virus must have infected you at some point in time. About 25% of people who develop hepatitis C antibodies in response to infection get rid of (or clear) the virus within 6 months. If people are able to clear the virus, the antibodies remain in the blood for some time, possibly the rest of their life. This means a positive antibody test doesn’t necessarily mean someone has the virus.
A different test, the Polymerase Chain Reaction (PCR) test is used to see whether you have the virus in your blood.

One situation when the antibody test is not reliable is in a newborn baby.
Babies born to mothers infected with hepatitis C can have a positive antibody test without actually being infected. This positive ‘maternal antibody’ usually only lasts 12 –18 months, therefore, it is recommended that testing of children should not be done until after this time.

http://www.hepatitisaustralia.com/about_hepatitis/treatment.html