Oral Fluid Results Research Articles

Window of detection of cocaine related alkaloids in oral fluid collected with the FloqSwab™ after coca tea consumption.

Coca tea is a popular drink in some countries of South America where it is presented as a safe energy preparation, based on a limited total content of cocaine of about 3 to 5 mg. Tea bags can be bought with no legal considerations in these countries both by locals and tourists but its consumption can have consequences when consumed overseas. Driving under the influence of cocaine is banned in most places in the world and can be documented by oral fluid testing. A study was implemented with coca tea bags (Coca & Muna) purchased in Peru, after a French attorney at law contacted the laboratory to assess the involvement of coca tea in the positive oral fluid results of a driver. Ten healthy volunteers consumed 250 mL of coca tea containing 4.5 mg of cocaine. No volunteer reported any change in behavioral effects after consumption of the coca tea. Oral fluid was collected with a swab (FloqSwab™, Copan) over 8 hours to follow the elimination of cocaine and its major metabolites (benzoylecgonine and ecgonine methylester). This is the procedure used by the French police. All samples were analyzed by UHPLC-MS-MS after Quantisal™ buffer desorption. As the device does not allow measurement of the amount of collected fluid, the results are qualitative. This is in accordance with the French law that requires a yes or no response about the presence of cocaine, with a minimum required performance level of 10 ng/ml of cocaine or benzoylecgonine. Parent cocaine was identified for 30 to 120 min. Benzoylecgonine and ecgonine methylester were identified between 1 and 8 hours, with a large inter-individual variation. Although it is generally accepted that a 4 to 5 mg cocaine dose has no significant pharmacological effect, the consumption of coca tea can lead to the suspension of a person's driving license due to a positive oral fluid test.

Application of oral fluid in SARS-CoV-2 nucleic acid and antibody detection

This study aimed to explore the application value of new biological specimen oral fluid in SARS-CoV-2 nucleic acid and antibody detection. Oral fluid and paired respiratory and blood specimens from 7 confirmed cases of two COVID-19 cluster epidemic were collected in Beijing from October to November 2021. SARS-CoV-2 virus and IgG antibody were detected by real time PCR kits and serum antibody detection reagents, and SARS-CoV-2 IgG antibody in oral fluids was detected by a new established method of magnetic particle chemiluminescence. The results showed that the nucleic acid amplification test of SARS-CoV-2 on nasopharyngeal swabs, throat swabs and oral fluid specimens from 3 confirmed cases of COVID-19 was positive, among which the Ct value for ORF1a/b and N gene of oral fluid samples in 2 cases was close to that of throat swab, and the Ct value of oral fluid sample for 1 case was higher than that of throat swab. The complete genome sequence of one oral fluid specimen was obtained, which belonged to the VOC/Delta variant strain. The SARS-CoV-2 IgG antibodies of the paired oral fluid and serum were all positive, and the S/CO values of oral fluid were all lower than those of serum. The series of oral fluid results showed that SARS-CoV-2 IgG antibody level increased from 11 to 32 days after the onset of the disease.

Bioaerosol and surface sampling for the surveillance of influenza A virus in swine

Influenza A virus in swine is of significant importance to human and veterinary public health. Environmental sampling techniques that prove practical would enhance surveillance for influenza viruses in swine. The primary objective of this study was to demonstrate the feasibility of bioaerosol and surface sampling for the detection of influenza virus in swine barns with a secondary objective of piloting a mobile application for data collection. Sampling was conducted at a large swine operation between July 2016 and August 2017. Swine oral fluids and surface swabs were collected from multiple rooms. Room-level air samples were collected using four bioaerosol samplers: a low volume polytetrafluoroethylene (PTFE) filter sampler, the National Institute for Occupational Safety and Health's low volume cyclone sampler, a 2-stage Andersen impactor and/or one high volume cyclonic sampler. Samples were analysed using quantitative RT-PCR. Data and results were reported using a mobile data application. Eighty-nine composite oral fluid samples, 70 surface swabs and 122 bioaerosol samples were analysed. Detection rates for influenza virus RNA in swine barn samples were 71.1% for oral fluids, 70.8% for surface swabs and 71.1% for the PTFE sampler. Analysis revealed a statistically significant relationship between the results of the PTFE sampler and the surface swabs with oral fluid results (p<0.001 and p<0.01 respectively). In addition, both the PTFE sampler (p<0.01) and surface swabs (p=0.03) significantly correlated with, and predicted oral fluid results. Bioaerosol sampling using PTFE samplers is an effective hands-off approach for detecting influenza virus activity among swine. Further study is required for the implementation of this approach for surveillance and risk assessment of circulating influenza viruses of swine origin. In addition, mobile data collection stands to be an invaluable tool in the field by allowing secure, real-time reporting of sample collection and results.

Detection of Hydrocodone and Morphine as Metabolites in Oral Fluid by LC-MS/MS in Patients Prescribed Codeine.

A retrospective analysis of oral fluid drug testing results using LC-MS/MS was performed to determine the prevalence rates in oral fluid for codeine (COD) and 3 COD metabolites-morphine (MOR), norhydrocodone (NHC), and hydrocodone (HCOD). Oral fluid samples were collected using Quantisal oral fluid collection device (Immunalysis Inc.) and submitted to Millennium Health, LLC for the routine drug analysis by LC-MS/MS. Consistent with previously published literature, COD was the primary analyte detected in oral fluid after the use of COD. In COD-positive samples, HCOD, MOR, and NHC were detected at rates of 68.4%, 18.4%, and 6.3%, respectively. Concentration ranges of these analytes were 1.0 to >2000 ng/mL for COD, 1.0-20.2 ng/mL for MOR, 1.0-740.0 ng/mL for HCOD, and 2.1-47.5 ng/mL for NHC. In contrast to urine, where HCOD is typically detected as a minor metabolite of COD, HCOD was the most commonly detected metabolite in oral fluid in samples testing positive for COD with reported prescriptions for COD. This observation suggests that care should be taken when interpreting HCOD positives in oral fluid results, and that the use of COD should be considered as one possible explanation for HCOD positives.

Comparison of PRRSV Nucleic Acid and Antibody Detection in Pen-Based Oral Fluid and Individual Serum Samples in Three Different Age Categories of Post-Weaning Pigs from Endemically Infected Farms.

BackgroundPorcine reproductive and respiratory syndrome virus (PRRSV) is the causative agent of an economically important disease in swine. Since it has been shown that PRRSV and PRRSV specific antibodies can be detected in oral fluid, many different aspects have been studied to show that oral fluid could be a worthy alternative diagnostic sample to serum for monitoring and surveillance of this disease. Thorough field evaluations are however missing to convincingly show its usefulness under representative field conditions.MethodologyPen-based oral fluid samples and serum samples from all individual pigs in the corresponding pens were collected from post-weaning pigs of three different age categories in eight endemically PRRSV infected farms and one PRRSV free farm in Belgium. All samples were tested by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and ELISA to detect PRRSV RNA and PRRSV specific antibodies, respectively.ResultsWhile the relative specificity of PRRSV detection by qRT-PCR in pen-based oral fluid compared to serum collected from individual pigs was high in all age categories (>90%), the relative sensitivity decreased with the age of the pigs (89, 93 and 10% in 8-12w, 16-20w and 24-28w old pigs, respectively). The latter correlated with a lower percentage of PRRSV positive pigs in serum/pen in the different age categories (55, 29 and 6%, respectively). Irrespective of the age category, pen-based oral fluid samples were always found PCR positive when at least 30% of the individual pigs were positive in serum. PRRSV specific antibody detection in oral fluid by ELISA showed a 100% relative sensitivity to detection in serum since oral fluid samples were always positive as soon as one pig in the pen was positive in serum. On the other hand, two false positive oral fluid samples in 11 pens without serum positive pigs were found, resulting in a relative specificity of 82%. Indications are however present that the oral fluid result indicated the correct infection status but the absence of a golden standard test makes it difficult to define definitive test characteristics.ConclusionsOverall it can be concluded that oral fluid seems to be a useful matrix for diagnosis of PRRSV under field conditions and that differences in kinetics of PRRSV and PRRSV specific antibody detection in oral fluid and serum of individual pigs can also be reflected in pen-based oral fluid results.

Extended Detection of Amphetamine and Methamphetamine in Oral Fluid.

Amphetamine and methamphetamine are popular drugs of abuse worldwide and are important components of drug monitoring programs. Windows of detection for amphetamine and methamphetamine in oral fluid after high doses have not been investigated. Repeated high-dose ingestions are likely to cause positive samples for extended periods. Common routes of administration of amphetamine/methamphetamine in Norway are oral intake or injection. The aim of this study was to investigate windows of detection for amphetamine and methamphetamine in oral fluid from drug addicts under sustained abstinence during detoxification. Twenty-five patients admitted to a closed detoxification unit were included in this study. Oral fluid samples were collected daily in the morning and evening, and urine every morning for 10 days. A blood sample was drawn during the first 5 days after admission if the patient consented. Oral fluid results were compared with urine results to determine whether a new ingestion occurred. Oral fluid was collected with the Intercept oral fluid collection device. In-house cutoff concentrations for amphetamine and methamphetamine were 6.8 and 7.5 mcg/L, respectively, in oral fluid, and 135 and 149 mcg/L, respectively, in urine. Amphetamines were detected in 11 oral fluid, 5 urine, and 2 blood specimens from 25 patients. Patients self-reported amphetamines intake of up to 0.5-2 g daily. Windows of detection for amphetamine and methamphetamine in oral fluid were up to 8 days, longer than in urine at the applied cutoff values. These data confirm that oral fluid is a viable alternative to urine for monitoring amphetamine abuse, and that these substances might be detected in oral fluid for at least 1 week after ingestion of high doses. Such long detection times were, as far as we are aware, never reported previously for oral fluid amphetamines.

Validation of an anti-measles virus-specific IgG assay with oral fluid samples for immunization surveillance in Bangladesh

Immune marker surveys may be used as substitutes or in conjunction with traditional surveys to monitor immunization program performance. This study assessed the validity and reliability of the Microimmune anti-measles virus-specific IgG ELISA with oral fluid samples (OF-ELISA) among a random sample of children ages 12–16 months in Bangladesh. Up to two oral fluid samples and one serum sample were analyzed for the presence of protective levels of anti-measles IgG antibodies. Results from the OF-ELISA were compared to the Enzygnost anti-measles IgG ELISA with serum and multivariate logistic regression models were developed to identify risk factors for false negative oral fluid results. Anti-measles IgG antibodies were measured in 330 paired oral fluid and serum samples. Immune marker prevalence of measles IgG antibodies was significantly higher in serum (88.1%, 95% CI: [84.1, 91.5]) than oral fluid (56.1% [50.2, 61.5]). Sensitivity (60.2% [54.1, 66.0]) and specificity (75.7% [58.8, 88.2]) of the OF-ELISA were lower than expected, but sensitivity significantly improved for individuals with higher anti-measles IgG in serum. False negative oral fluid results were associated with month of sample collection and variability between data collectors and assay procedures. Due to poor performance, caution should be exercised when using oral fluid samples to assess population immunity to measles virus, especially in highly vaccinated populations.

Will Patients “Opt In” to Perform Their Own Rapid HIV Test in the Emergency Department?

We evaluate the feasibility and accuracy of existing point-of-care HIV tests performed by an untrained patient compared with the routinely used HIV point-of-care test offered to patients in 2 urban emergency departments (EDs). From April 2008 through December 2009, patients who had completed a standard HIV oral fluid test performed by a trained health care professional and who were unaware of their results were recruited to perform a rapid point-of-care HIV test. Patients were given a choice of the oral fluid or the fingerstick blood point-of-care test. Evaluation of acceptability to perform the mechanics of the test was accessed by questionnaire. For the "self-test," the participant obtained his or her own sample and performed the test. The patient's results were compared with standard oral fluid results obtained by the health care professional. Overall, 478 of 564 (85%) patients receiving a standard oral fluid HIV test volunteered, with a mean age of 38 to 39 years. Ninety-one percent of participants chose oral fluid and 9% chose blood (P<.05). Self-test results were 99.6% concordant with health care professionals' test results. For the self-testers, 94% of oral fluid testers and 84.4% of blood testers reported trusting the self-administered test result "very much." Furthermore, 95.6% of the oral fluid group and 93.3% of the blood group would "probably" or "definitely" perform a test at home, if available. This study demonstrated that a significant proportion of patients offered a self-HIV point-of-care test volunteered and preferred using oral fluid. Patients' results agreed with standard HIV point-of-care results. The majority of participants trusted their results and would perform a point-of-care HIV test at home, given the opportunity.

Investigation of False Positive Results with an Oral Fluid Rapid HIV-1/2 Antibody Test

BackgroundIn March 2004, the OraQuick® rapid HIV antibody test became the first rapid HIV test approved by the US Food and Drug Administration for use on oral fluid specimens. Test results are available in 20 minutes, and the oral fluid test is non-invasive. From August 2004–June 2005, we investigated a sudden increase in false-positive results occurring in a performance study of OraQuick® oral-fluid rapid HIV tests in Minnesota.Methodology/Principal FindingsIn a field investigation, we reviewed performance study data on oral-fluid and whole-blood OraQuick® rapid HIV test device lots and expiration dates and assessed test performance and interpretation with oral-fluid and whole-blood specimens by operators who reported false-positive results. We used multivariate logistic regression to evaluate client demographic and risk characteristics associated with false-positive results. Next, we conducted an incidence study of false-positive OraQuick rapid HIV tests in nine US cities and tested both oral-fluid and finger-stick whole-blood specimens from clients; reactive tests were confirmed with Western blot. Sixteen (4.1%) false-positive oral-fluid results occurred in the performance study from April 15, 2004 through August 31, 2004 with unexpired devices from six test lots among 388 HIV-uninfected clients (specificity, 95.9%; 95% CI: 93.4–97.6). Three test operators who had reported false-positive results performed and interpreted the test according to package-insert instructions. In multivariate analysis, only older age was significantly associated with false-positive results (adjusted odds ratio = 4.5, 95% CI: 1.2–25.7). In the incidence study, all valid oral-fluid and whole-blood results from 2,268 clients were concordant and no false-positive results occurred (100% specificity).Conclusions/SignificanceThe field investigation did not identify a cause for the increase in false-positive oral-fluid results, and the incidence study detected no false-positive results. The findings suggest this was an isolated cluster; the test's overall performance was as specified by the manufacturer.

Passive Cannabis Smoke Exposure and Oral Fluid Testing. II. Two Studies of Extreme Cannabis Smoke Exposure in a Motor Vehicle

Two studies were conducted to determine if extreme passive exposure to cannabis smoke in a motor vehicle would produce positive results for delta-tetrahydrocannabinol (THC) in oral fluid. Passive exposure to cannabis smoke in an unventilated room has been shown to produce a transient appearance of THC in oral fluid for up to 30 min. However, it is well known that such factors as room size and extent of smoke exposure can affect results. Questions have also been raised concerning the effects of tobacco when mixed with marijuana and THC content. We conducted two passive cannabis studies under severe passive smoke exposure conditions in an unventilated eight-passenger van. Four passive subjects sat alongside four active cannabis smokers who each smoked a single cannabis cigarette containing either 5.4%, 39.5 mg THC (Study 1) or 10.4%, 83.2 mg THC (Study 2). The cigarettes in Study 1 contained tobacco mixed with cannabis; cigarettes in Study 2 contained only cannabis. Oral fluid specimens were collected from passive and active subjects with the Intercept Oral Specimen Collection Device for 1 h after smoking cessation while inside the van (Study 1) and up to 72 h (passive) or 8 h (active) outside the van. Additionally in Study 1, Intercept collectors were exposed to smoke in the van to assess environmental contamination during collection procedures. For Study 2, all oral fluid collections were outside the van following smoking cessation to minimize environmental contamination. Oral samples were analyzed with the Cannabinoids Intercept MICRO-PLATE EIA and quantitatively by gas chromatography-tandem mass spectrometry (GC-MS-MS). THC concentrations were adjusted for dilution (x 3). The screening and confirmation cutoff concentrations for THC in neat oral fluid were 3 ng/mL and 1.5 ng/mL, respectively. The limits of detection (LOD) and quantitation (LOQ) for THC in the GC-MS-MS assay were 0.3 and 0.75 ng/mL, respectively. Urine specimens were collected, screened (EMIT, 50 ng/mL cutoff), and analyzed by GC-MS-MS for THCCOOH (LOD/LOQ = 1.0 ng/mL). Peak oral fluid THC concentrations in passive subjects recorded at the end of cannabis smoke exposure were up to 7.5 ng/mL (Study 1) and 1.2 ng/mL (Study 2). Thereafter, THC concentrations quickly declined to negative levels within 30-45 min in Study 1. It was found that environmentally exposed Collectors contained 3-14 ng/mL in Study 1. When potential contamination during collection was eliminated in Study 2, all passive subjects were negative at screening/confirmation cutoff concentrations throughout the study. Oral fluid specimens from active smokers had peak concentrations of THC approximately 100-fold greater than passive subjects in both studies. Positive oral fluid results were observed for active smokers 0-8 h. Urine analysis confirmed oral fluid results. These studies clarify earlier findings on the effects of passive cannabis smoke on oral fluid results. Oral fluid specimens collected in the presence of cannabis smoke appear to have been contaminated, thereby falsely elevating THC concentrations in oral fluid. The risk of a positive test for THC was virtually eliminated when specimens were collected in the absence of THC smoke.

Development and evaluation of Varicella zoster virus ELISA for oral fluid suitable for epidemiological studies

An enzyme-linked immunosorbent assay (ELISA) for detection of Varicella zoster virus (VZV) antibodies in oral fluid is described. The assay was optimised and evaluated using paired serum and oral fluid from healthy adult volunteers ( n = 205) and preschool children ( n = 98), oral fluid samples collected for routine measles, mumps and rubella testing ( n = 537) and samples from a study of atopic dermatitis ( n = 252). As chickenpox is predominantly a childhood disease and most adults are immune, it was crucial to have samples from children aged 1–5 years to evaluate the assay. Mixture modelling of the oral fluid results was used to determine the optimum cut-off, sensitivity and specificity of the assay. Compared to paired sera tested by the same ELISA the sensitivity of the oral fluid assay was 93% and specificity 95.7% overall, varying slightly with age group. The assay was shown to have good potential for use in large-scale epidemiological studies.