Detection of hepatitis C virus RNA in the cell fraction of saliva before and after oral surgery.

The presence of hepatitis C virus (HCV) RNA in serum, whole saliva, and saliva from the submaxillary glands was investigated before and after oral surgery. The presence of HCV RNA (positive and negative-strand RNA) was determined in serum and saliva by a nested polymerase chain reaction in 26 anti-HCV positive patients, of whom 11 were coinfected with human immunodeficiency virus-1. Oral surgery was carried out on five occasions on four of the patients. HCV RNA was detected in the sera of 23 of 26 (88%) patients, and in the saliva of 4 of the 23 (17%) of the viremic patients. In all four cases, HCV RNA was detected only in the cell fraction derived from centrifugation of whole saliva. Negative-stranded HCV RNA was not detected. At one of five occasions of oral surgery, HCV RNA was detected in saliva sampled immediately after surgery, but not before or 24 hours after surgery. The results suggest that HCV is present in saliva in less than 25% of HCV viremic persons. The presence of the virus in saliva is restricted to the cell fraction. Thus, saliva may serve as a possible, but low, nonparenteral transmission route of HCV. Contamination of saliva by blood during and after oral surgery may result in an increased risk of viral exposure. Except for trauma caused by sharp instruments during surgery, this might contribute to the higher HCV seropositivity found among dentists.