Does the Hep C virus replicate in stored blood?

October 31, 2006 11:58 AM

Can the Hep C virus replicate in vials of stored blood?

The scenario: Say 15 years ago a healthcareworker gets accidently pricked by a needle from a Hep C positive patient. Blood is drawn, tested for Hep C, and properly stored away. I realize that s/he would not test positive for Hep C for weeks- months-years later. But does the Hep C virus replicate in that original sample that was taken? If one were to go back and re-test that original blood sample(taken 15 yrs ago), would it be positive?

I know that if this were to happen present day, the worker would be tested at baseline and then followed for a period of time. Was this not the case back then?

Thanks

posted by engling to Science & Nature (4 answers total)

The sample would probably not be positive because it was frozen. Viral and cellular metabolism doesn't occur in frozen samples and some protein degradation may have occurred, further inhibiting detection. However, detection methods are probably more sensitive today so its possible if the blood contained Hep C it would show up positive today when it previously had not (assuming the worker was actually infected.)
posted by dendrite at 12:06 PM on October 31, 2006

The answer's no, for a couple of reasons.

First recall that viruses can't do anything by themselves. They require cells, and the cellular machinery, to replicate. They're obligate parasites - they require the "factories" of the cell to create more copies of themselves.

Blood contains cells, but most red cells don't have any of the organelles (nucleus, endoplasmic reticulum, Golgi, etc) that the virus needs to be able to replicate. That leaves white blood cells.

A quick look at PubMed didn't reveal whether or not the Hep C virus replicates in leukocytes. We know it replicates in liver cells. If it could replicate in leukocytes (which I doubt), maybe it could produce a few more viruses. But there are so few leukocytes in a blood sample - just a few thousand per microliter, I think - that it's not going to amount to a hill of beans.

Second, blood is stored at cold conditions - usually frozen, if for 15 years - at which all life processes cease. No cellular activity takes place in freezing conditions. No viruses would replicate under those conditions.
posted by ikkyu2 at 12:10 PM on October 31, 2006

Googling a bit on "hepatitis c virus" culture reveals that just this year was the first time that researchers reported successfully culturing infectious hepatitis C virus outside a living organism when they were trying to do exactly that. That's in any type of cell at all, and they had to use liver cells. And even then they had to use a modified form of HCV not found in nature--it has genes taken from two different naturally occuring HCV strains. That should give you an idea of how hard it is to get HCV to replicate outside a live animal. If it simply replicated in stored blood, I doubt it would have taken scientists that long to figure it out.
posted by DevilsAdvocate at 2:37 PM on October 31, 2006

Durn viruses! Pesky; elusive.

Hep C used to be called "non-A, non-B hepatitis." I recall that its isolation/discovery was felt to be quite a feat.
posted by ikkyu2 at 3:02 PM on October 31, 2006