The search for hepatitis C virus (HCV) in body fluids other than blood is important when assessing possible nonparenteral routes of viral transmission. However, the role of oral fluids in HCV transmission remains controversial. Here we quantitatively determined HCV RNA in saliva and gingival crevicular fluid (GCF) of anti-HCV-positive patients. Most patients (14 of 18; 78%) whose saliva specimens were negative had HCV RNA in their GCF. Most patients (20 of 26; 77%) had higher HCV RNA levels in their GCF than in their saliva. Although there was not a statistically significant correlation between the serum viral load and HCV level in saliva or GCF, patients with low serum HCV loads were less likely to have detectable HCV in their saliva. These findings have important implications for medical personnel and suggest that epidemiological studies designed to understand the significance of the oral route of transmission of HCV are warranted.Hepatitis C virus (HCV) infection represents a major public health problem in the world today. The infection primarily causes liver disease; however, HCV infection has also been associated with extrahepatic abnormalities, including mixed cryoglobulinemia, malignant lymphoma, Sjögren's syndrome, and oral lichen planus (2,12,18,19,34,39). Lymphotropism of HCV has been observed, and several laboratories have detected the virus in blood mononuclear cells (BMC) (16,22,26,28,35,38). Common risk factors for HCV infection include blood transfusion from unscreened donors as well as injection drug use. Although sexual and vertical transmissions have also been reported, there remain a large number of HCV carriers in whom no route of infection has been identified.Epidemiological surveys demonstrate that body fluids other than blood, including saliva, might be potential sources of HCV infection. Experimental inoculation of saliva obtained from chronic HCV carrier chimpanzees has been reported to transmit hepatitis to recipient animals (1). Several studies have demonstrated HCV RNA in the saliva of hepatitis C patients by reverse transcription (RT)-nested PCR. However, the detection rates of viral RNA within saliva have varied widely, and some groups have failed to demonstrate HCV RNA within saliva (6-11, 14, 17, 23, 25, 27, 29-33, 36-38). A potential source of HCV RNA within saliva includes gingival crevicular fluid (GCF), which might contain HCV-infected BMC in the setting of periodontal inflammation. To our knowledge, only one study has qualitatively identified HCV in GCF; HCV RNA was detected in 59% of GCF specimens from hepatitis C patients in the study (20). Since the efficiency of HCV transmission is likely related to its viral load, it is important to quantitate viral RNA levels within body fluids in order to properly evaluate possible nonparenteral routes of HCV infection.Thus, we examined the presence of HCV RNA in the saliva and GCF of anti-HCV antibody-positive patients using realtime quantitative RT-PCR.
MATERIALS AND METHODSSample collection. Twenty-six dental patients attending the ...