Virus RNA In Saliva Research Articles

Detection of hepatitis E virus RNA in saliva for diagnosis of acute infection.

Diagnosis of acute hepatitis E virus (HEV) infection is established by detection of anti-HEV IgM antibodies by ELISA or by amplification of serum viral RNA. Here, we evaluate the diagnostic value of testing HEV RNA in saliva to identify patients with acute HEV infection. Prospective proof-of-concept study including patients with acute hepatitis. Whole blood and neat saliva samples were obtained from all patients. Saliva samples were processed and analysed for HEV RNA by RT-PCR within 2hr after collection. A total of 34 patients with acute hepatitis and 12 healthy donors were included in the study. HEV RNA in serum was confirmed by RT-PCR in eight of these patients (23.5%; 95% CI: 12.2%-40.2%). HEV was isolated in the saliva of eight of 34 patients (23.5%; 95% CI: 12.2%-40.2%). All patients with HEV RNA amplified in saliva had detectable HEV RNA in serum. HEV was isolated neither in the saliva of any of the 26 patients without detectable HEV RNA in serum nor in healthy donors. Our study suggests that acute HEV infection could be diagnosed by assessing viral load in saliva.

Detection of hepatitis C virus RNA in saliva of patients with active infection not associated with periodontal or liver disease severity.

BackgroundHepatitis C virus (HCV) is mainly transmitted by parenteral route, being blood transfusion and intravenous drug use the most frequent risk factors. However, it has been suggested that there are other routes of transmission. There are several studies where HCV RNA has been detected in saliva of patients infected with HCV, and epidemiological studies have proposed the dental treatments as possible risk factors for HCV transmission. The purpose of this study was to detect the presence of HCV RNA in saliva of patients with active infection and associating with periodontal or liver disease.MethodsPatients with quantifiable HCV-RNA in serum were enrolled in the study. Periodontal disease was assessed using the modified gingival index (MGI). Presence of dental plaque was assessed with the use of disclosing tablets. Patients were clinically and laboratory evaluated to identify the stage of liver disease, the HCV RNA was determinate in saliva by nested RT-PCR. To determine associations between different parameters univariate and multivariate analysis were used.ResultsA total of 45 patients were included. Of these patients, 21 (46.6%) had hepatitis, 23 (51.1%) had cirrhosis and one patient (2.4%) presented hepatocellular carcinoma (HCC). Viral loads in serum ranged from 2.31–6.68 log IU/ml with a mean of 5.46 log IU/ml (95% CI 5.23–5.70). HCV RNA was positive in saliva of 29 patients (64.4%) and was not detected in 16 (35.6%). For univariate analysis three independent variables were associated with the detection of HCV-RNA in saliva: gender, viral load and dental plaque and multivariate analysis only one independent variable viral load >5.17 log IU/mL remained significantly associated with the detection of HCV in saliva (p = 0.0002). A statistical difference was observed when viral load was analyzed, log 5.85 IU/mL (95% CI 5.67–6.02) for patients with HCV in saliva vs. log 4.77 IU/mL (95% CI 4.35–5.19) for patients without HCV in saliva (p = 0.0001). The detection of HCV-RNA in saliva was more frequent in patients with relatively high serum viral loads.ConclusionHCV-RNA in saliva was associated with the level of serum viral load but not with periodontal or liver disease severity.

Sensitivity and specificity of immunoglobulin G titer for the diagnosis of mumps virus in infected patients depending on vaccination status

The aim of the study was to evaluate the usefulness of serological detection of mumps IgM and titration of IgG in patients with acute parotitis according to their vaccination status. The detection of mumps virus RNA in saliva by RT-PCR was used as reference. 116 patients (109 of them previously vaccinated) with mumps RT-PCR-negative results and 21 (19 vaccinated) with mumps RT-PCR-positive results were studied. Mumps-specific IgM and IgG were assayed by EIA (Enzygnost, Dade Behring, Germany). IgM results were expressed as positive or negative. For IgG, several cut-offs were calculated using receiver operating characteristic (ROC) curves. Seven RT-PCR-positive and five RT-PCR-negative patients showed IgM-positive results (sensitivity 33.3% and specificity 95.7%). Among vaccinated patients, the sensitivity and specificity of IgM were 26.3% (5/19) and 99.1% (108/109). For IgG, a titer of 5,000 in all the patients showed a sensitivity of 76.2% (16/21) and a specificity of 83.6% (97/116). In vaccinated patients, the corresponding figures for this cut-off were 84.2% (16/19) and 83.5% (91/109), respectively. Although IgM detection against mumps is highly specific, its sensitivity is very low in immunized subjects. In this group, the titration of IgG could serve as an additional diagnostic tool.

Detection of Feline Leukemia Virus RNA in Saliva from Naturally Infected Cats and Correlation of PCR Results with Those of Current Diagnostic Methods

A novel diagnostic test for feline leukemia virus (FeLV) RNA in saliva from naturally infected cats is described in this study. We evaluated different diagnostic tests and compared them with the widely used enzyme-linked immunosorbent assay (ELISA) for the detection of p27 in the diagnosis of FeLV. Blood samples from 445 cats were tested for the presence of provirus by real-time PCR and plasma and saliva specimens from those cats were tested for the presence of viral RNA by real-time reverse transcription (RT)-PCR and for the presence of p27 by ELISA. In comparison to conventional ELISA, the diagnostic sensitivity and specificity of the detection of salivary FeLV RNA by real-time RT-PCR were found to be 98.1 and 99.2%, respectively. Detection of viral RNA in saliva had a positive predictive value of 94.6% and a negative predictive value of 99.7%. The kappa value was 0.96, demonstrating an almost perfect agreement between both tests. Furthermore, we confirmed previous results showing that a number of cats which tested negative for the presence of p27 in plasma were in fact positive for the presence of DNA provirus in blood specimens (5.4%). However, 96.4% of these latently infected cats did not shed viral RNA in saliva; therefore, we assume that these cats are of relatively low clinical importance at the time of testing. This study shows considerable diagnostic value of the detection of saliva FeLV RNA in naturally infected cats. This new diagnostic method has advantages over the conventional ELISA, such as less invasive sample collection and no requirement for trained personnel.

Detection of Hepatitis C Virus-RNA in Saliva from Chronically HCV-Infected Patients

The possibility of the non-parenteral Hepatitis C Virus (HCV) transmission is supported by the demonstration that the actual virus is present in several body fluids, including saliva. From a review of the literature many investigators have found the presence of HCV-RNA in saliva, however, widely contrasting results emerge, with detection rates ranging from 0-100%. To further examine HCV salivary shedding, saliva samples were collected from 46 chronically HCV-infected patients and tested for HCV-RNA and occult blood. Quantification and genotyping of serum HCV-RNA were also carried out for each patient. HCV-RNA was detected in 39.13% of the saliva samples. The viral salivary shedding was significantly related to viraemia levels, serum viral genotype and the presence of salivary occult blood. Our findings indicate that the HCV salivary shedding occurs in about one third of HCV infected patients, but seem to suggest that it is unlikely when the serum viral genotype is 3a. Moreover, blood leakage into the oral cavity is possibly the main source of the salivary HCV-RNA. Although the occurrence of the viral salivary shedding does not necessarily mean that HCV transmission occurs by saliva, our results suggest the need for further investigations into the biological factors possibly involved in HCV mucosal transmission related to both the source and the exposed subjects.

Shedding of feline leukemia virus RNA in saliva is a consistent feature in viremic cats

The purpose of this investigation was to characterize the shedding pattern of feline leukemia virus (FeLV) RNA in saliva, and to correlate it with the proviral load in whole blood, viral load in plasma, levels of p27 in saliva and plasma, the isolation of infectious FeLV from saliva, and the titers of FeLV-specific antibodies of the IgG and IgA isotypes. We evaluated 24 experimentally FeLV-infected cats for these parameters using real-time RT-PCR and PCR, cell culture assay and sandwich ELISA. We observed that shedding of viral RNA in saliva was a consistent feature in viremic cats. Latently FeLV-infected cats, displaying a very low proviral load, did not shed infectious virus in saliva, but occasionally shed viral RNA. Consequently, salivary shedding of FeLV RNA may not necessarily indicate a transmission potential for susceptible cats. This study also confirmed previous results from our laboratory, showing that a negative result for p27 in plasma, or for viral RNA in plasma or saliva does not exclude FeLV infection, considering that blood cells from those cats contained provirus. We also showed that FeLV RNA and DNA were stable for more than 64 days in saliva samples stored at room temperature. We conclude that the detection of FeLV RNA in saliva may be a useful indicator of viremia, and that the detection of salivary viral RNA by RT-PCR could become a reliable tool for the diagnosis of FeLV infection, which is facilitated by the low invasive method of collection of the samples.

Detection of hepatitis C virus RNA in saliva is not related to oral health status or viral load

Hepatitis C is a worldwide public health problem and its transmission is clearly associated with the parenteral route, however, the virus has also been isolated from other body fluids. Hepatitis C virus (HCV) RNA has been detected in saliva, yet the relationship between HCV and oral pathology is not clearly understood. Therefore, an investigation on HCV-RNA in saliva and its correlation with oral pathology was undertaken. Saliva and blood samples were collected from 50 anti-HCV positive patients and from 25 patients with non-HCV chronic liver disease. HCV-RNA was detected in all of the saliva samples from the HCV positive group. None of the saliva or serum samples from the non-HCV group were positive for HCV-RNA. The patients were examined for dental and oral health (dentate, partially dentate, edentulous, evidence of gum disease, or mucosal lesions); however, no correlation was found between HCV-RNA in saliva, oral health, and viral load. These results suggest that HCV-RNA presence in saliva is independent of the viral load and the oral pathology of HCV positive individuals.

Detection of hepatitis A virus RNA in saliva.

Hepatitis A virus (HAV) is shed in feces but also in saliva. HAV RNA was detected in saliva in five out of six acutely infected patients with HAV viremia. Serum and saliva sequences were identical. The simplicity of obtaining material allows the recommendation of the use of saliva for investigation of outbreaks.

Quantitation of hepatitis C virus RNA in saliva and serum of patients coinfected with HCV and human immunodeficiency virus

The presence and the quantity of hepatitis C virus (HCV) RNA were investigated in saliva and serum of patients infected with both HCV and human immunodeficiency virus (HIV). Paired serum and saliva samples were collected from 59 HIV-HCV coinfected patients. HCV RNA was detected by nested-PCR, using primers derived from the 5′ non-coding region of HCV, and positive results were quantified using the b-DNA method. HCV RNA was detected in the saliva of 22/59 (37.3%) patients, with a mean level of 1.15 × 106 genome equivalents/ml; there was no correlation of salivary positivity with immune status (CD4 cell count), age or HIV risk group, but there was with gender (19/38 [50%] positive results in male, compared to 3/21 [14.3%] in female, P = 0.007). HCV RNA was detected in the serum of 45/59 (76.3%) patients at a higher level (mean of 2.52 × 107 genome equivalents/ml) compared to saliva. Positivity was not correlated with age, gender or CD4 + cell count. There was a correlation between qualitative saliva and serum results (P = 0.003), but not between quantifications (P = 0.57). This first study reporting significant amounts of HCV RNA in saliva could have important implications for HCV epidemiology. J. Med. Virol. 63:117–119, 2001. © 2001 Wiley-Liss, Inc.

Quantitation of hepatitis C virus RNA in saliva and serum of patients coinfected with HCV and human immunodeficiency virus

The presence and the quantity of hepatitis C virus (HCV) RNA were investigated in saliva and serum of patients infected with both HCV and human immunodeficiency virus (HIV). Paired serum and saliva samples were collected from 59 HIV-HCV coinfected patients. HCV RNA was detected by nested-PCR, using primers derived from the 5' non-coding region of HCV, and positive results were quantified using the b-DNA method. HCV RNA was detected in the saliva of 22/59 (37.3%) patients, with a mean level of 1.15 x 10(6) genome equivalents/ml; there was no correlation of salivary positivity with immune status (CD4 cell count), age or HIV risk group, but there was with gender (19/38 [50%] positive results in male, compared to 3/21 [14.3%] in female, P = 0.007). HCV RNA was detected in the serum of 45/59 (76.3%) patients at a higher level (mean of 2.52 x 10(7) genome equivalents/ml) compared to saliva. Positivity was not correlated with age, gender or CD4 + cell count. There was a correlation between qualitative saliva and serum results (P = 0.003), but not between quantifications (P = 0.57). This first study reporting significant amounts of HCV RNA in saliva could have important implications for HCV epidemiology.

Detection of HCV-RNA in saliva of patients with chronic hepatitis C.

Previous studies have provided conflicting results on the presence of hepatitis C virus-RNA in saliva. In this study, 23 (62%) of 37 patients tested positive for hepatitis C virus-RNA in saliva, using polymerase chain reaction analysis. A slightly greater proportion had a sporadic rather than a parenteral origin of chronic hepatitis C. These results provide a biological basis for saliva as a possible source of hepatitis C virus (HCV) infection, but do not necessarily imply transmission by this route.

Hepatitis C virus RNA in saliva of patients with posttransfusion hepatitis and low efficiency of transmission among spouses.

In a prospective study of posttransfusion hepatitis, 14 patients who were diagnosed with posttransfusion hepatitis C were enrolled randomly for the study of hepatitis C virus (HCV) RNA in saliva. Saliva and serum samples were collected on the same day. Spouses of 11 married patients were also tested for anti-C100 and HCV RNA. Paired serum and saliva samples were tested for HCV RNA by a nested polymerase chain reaction (PCR). Two primer pairs specific for the non-coding region of HCV were used for the PCR and a oligonucleotide sequence between the primers was used as the probe for Southern hybridization. Six patients were positive for HCV RNA by first round PCR amplification and an additional four patients were detected after second round PCR. All patients were negative for HCV RNA in saliva after first round PCR, while seven were positive after second round PCR amplification. All seven patients were positive for HCV RNA in paired serum samples. HCV RNA was detectable in saliva from 1 week to 38 months after the onset of hepatitis. All spouses were negative for anti-C100 and HCV RNA. We conclude that HCV RNA is present in the saliva of approximately half of patients with acute and chronic hepatitis C, and the presence of HCV RNA correlates with HCV viremia. The efficiency of HCV transmission is low among spouses.