Those who relapse an extended period of time after achieving a cure for hepatitis C virus (HCV) may not have been reinfected with a different strain of virus, but may be experiencing a resurfacing of the original infection, Healio reports. Publishing their findings in The Journal of Infectious Diseases, researchers analyzed RNA sequences of hep C in both serum and liver tissue that were taken from 103 study participants who achieved a sustained virologic response (SVR, considered a cure) after receiving interferon-based therapy between 1985 and 2005.

Three people in the study group relapsed late, yielding a positive hep C RNA test a respective 8, 75 and 78 months post SVR. Then there were four participants who relapsed early; they served as the study’s control group.

Investigators sequenced serum samples from both before the participants began hep C treatment and after they relapsed. They found that there was a 99.4 percent sequence match between the two serum samples among the early relapse participants and a 99.8 percent match between the samples among the late relapsers. The strains of virus also had the same genotype between the sample pairs in all cases. The implication is that no new viral strain was introduced in the late relapsers.

The researchers state that the liver in particular can harbor hep C after an SVR. Further research is needed to determine how such low levels of viral RNA can persist for extended periods after a cure.

To read the Healio story, click here.

To read the study abstract, click here.