Simple workflow to repurpose SARS-CoV-2 swab/serum samples for the isolation of cost-effective antibody/antigens for proteotyping applications and diagnosis.

Supply shortage for the development and production of preventive, therapeutic, and diagnosis tools during the COVID-19 pandemic is an important issue affecting the wealthy and poor nations alike. Antibodies and antigens are especially needed for the production of immunological-based testing tools such as point-of-care tests. Here, we propose a simple and quick magnetic nanoparticle (MNP)-based separation/isolation approach for the repurposing of infected human samples to produce specific antibodies and antigen cocktails. Initially, an antibody cocktail was purified from serums via precipitation and immunoaffinity chromatography. Purified antibodies were conjugated onto MNPs and used as an affinity matrix to separate antigens. The characterization process was performed by ELISA, SDS-PAGE, electrochemistry, isothermal titration calorimetry, and LC-Q-TOF-MS/MS analyses. The MNP-separated peptides can be used for mass spectrometry-based as well as paper-based lateral flow assay diagnostic. The exploitation of the current workflow for the development of efficient diagnostic tools, specific treatments, and fundamental research can significantly impact the present or eventual pandemic. This workflow can be considered as a two birds, one stone-like strategy.

A Phase 1, Open-Label Assessment of a Dengue Virus-1 Live Virus Human Challenge Strain.

BACKGROUND: Dengue human infection models (DHIM) have been used as a safe means to test the viability of prophylaxis and therapeutics. METHODS: A phase 1 study of 12 healthy adult volunteers using a challenge virus, DENV-1-LVHC strain 45AZ5, was performed. A dose escalating design was used to determine the safety and performance profile of the challenge virus. Subjects were evaluated extensively until 28 days and then out to 6 months. RESULTS: Twelve subjects received the challenge virus: 6 with 0.5 mL of 6.5 × 103 plaque-forming units (PFU)/mL (low-dose group) and 6 with 0.5 mL of 6.5 × 104 PFU/mL (mid-dose group). All except 1 in the low-dose group developed detectable viremia. For all subjects the mean incubation period was 5.9 days (range 5-9 days) and mean time of viremia was 6.8 days (range 3-9 days). Mean peak for all subjects was 1.6 × 107 genome equivalents (GE)/mL (range 4.6 × 103 to 5 × 107 GE/mL). There were no serious adverse events or long-term safety signals noted. CONCLUSIONS: We conclude that DENV-1-LVHC was well-tolerated, resulted in an uncomplicated dengue illness, and may be a suitable DHIM for therapeutic and prophylactic product testing. CLINICAL TRIALS REGISTRATION: NCT02372175.

Genotype-Informed Versus Empiric Management Of VirEmia (GIVE MOVE): study protocol of an open-label randomised clinical trial in children and adolescents living with HIV in Lesotho and Tanzania.

BACKGROUND: Globally, the majority of people living with HIV have no or only limited access to HIV drug resistance testing to guide the selection of antiretroviral drugs. This is of particular concern for children and adolescents, who experience high rates of treatment failure. The GIVE MOVE trial assesses the clinical impact and cost-effectiveness of routinely providing genotypic resistance testing (GRT) to children and adolescents living with HIV who have an unsuppressed viral load (VL) while taking antiretroviral therapy (ART). METHODS: GIVE MOVE is an open-label randomised clinical trial enrolling children and adolescents (≥6 months to <19 years) living with HIV with a VL ≥400 copies/mL (c/mL) while taking first-line ART. Recruitment takes place at sites in Lesotho and Tanzania. Participants are randomised in a 1:1 allocation to a control arm receiving the standard of care (3 sessions of enhanced adherence counselling, a follow-up VL test, continuation of the same regimen upon viral resuppression or empiric selection of a new regimen upon sustained elevated viremia) and an intervention arm (GRT to inform onward treatment). The composite primary endpoint is the occurrence of any one or more of the following events during the 36 weeks of follow-up period: i) death due to any cause; ii) HIV- or ART-related hospital admission of ≥24 h duration; iii) new clinical World Health Organisation stage 4 event (excluding lymph node tuberculosis, stunting, oral or genital herpes simplex infection and oesophageal candidiasis); and iv) no documented VL <50 c/mL at 36 weeks follow-up. Secondary and exploratory endpoints assess additional health-related outcomes, and a nested study will assess the cost-effectiveness of the intervention. Enrolment of a total of 276 participants is planned, with an interim analysis scheduled after the first 138 participants have completed follow-up. DISCUSSION: This randomised clinical trial will assess if the availability of resistance testing improves clinical outcomes in children and adolescents with elevated viremia while taking ART. TRIAL REGISTRATION: This trial is registered with ClinicalTrials.gov ( NCT04233242 ; registered 18.01.2020). More information: www.givemove.org .

Temporal Changes and Regional Variation in Acceptance of Hepatitis C Virus-Viremic Livers.

The high efficacy of current hepatitis C virus (HCV) therapy and increased numbers of HCV-infected deceased donors have changed the paradigm of HCV in liver transplantation (LT). Modeling studies have been performed to evaluate the optimal timing of HCV treatment (before versus after LT) in HCV-infected patients and to assess the cost-effectiveness of transplanting HCV-infected livers into HCV- patients. However, these models rely on historical data and have not quantified the temporal changes in the median Model for End-Stage Liver Disease (MELD) score at transplant of recipients of an HCV-infected liver across geographic areas. We performed a retrospective cohort study of Organ Procurement and Transplantation Network/United Network for Organ Sharing (UNOS) data of nonstatus 1 deceased donor LT recipients from January 1, 2016, to December 31, 2018, and we calculated the difference in allocation MELD score in recipients of HCV nucleic acid test (NAT)- versus NAT+ livers by year and UNOS region. We used Pearson correlation coefficients to assess the relationship between MELD score difference in recipients of HCV NAT+ versus HCV NAT- livers and the proportion of non-HCV recipients of HCV NAT+ livers. Nationally, the allocation MELD score difference at LT in recipients of HCV NAT+ versus NAT- livers did not change (4-point difference). This stability was seen in regions 3, 5, and 10. In regions 1, 7, 8, 9, and 11, the MELD score difference decreased, which is a diminishing advantage. However, in regions 2 and 4, it increased, which is a rising advantage. In 2018, recipients of HCV NAT+ livers had a lower MELD score in 9/11 regions, and the MELD score advantage of accepting HCV NAT+ livers had a moderate inverse correlation with the regional use in non-HCV patients (r = -0.53). These data should be used to inform clinicians of the pre- and post-LT trade-offs of HCV treatment.

Detection of post-vaccination enhanced dengue virus infection in macaques: An improved model for early assessment of dengue vaccines.

The need for improved dengue vaccines remains since the only licensed vaccine, Dengvaxia, shows variable efficacy depending on the infecting dengue virus (DENV) type, and increases the risk of hospitalization for severe dengue in children not exposed to DENV before vaccination. Here, we developed a tetravalent dengue purified and inactivated vaccine (DPIV) candidate and characterized, in rhesus macaques, its immunogenicity and efficacy to control DENV infection by analyzing, after challenge, both viral replication and changes in biological markers associated with dengue in humans. Although DPIV elicited cross-type and long-lasting DENV-neutralizing antibody responses, it failed to control DENV infection. Increased levels of viremia/RNAemia (correlating with serum capacity at enhancing DENV infection in vitro), AST, IL-10, IL-18 and IFN-γ, and decreased levels of IL-12 were detected in some vaccinated compared to non-vaccinated monkeys, indicating the vaccination may have triggered antibody-dependent enhancement of DENV infection. The dengue macaque model has been considered imperfect due to the lack of DENV-associated clinical signs. However, here we show that post-vaccination enhanced DENV infection can be detected in this model when integrating several parameters, including characterization of DENV-enhancing antibodies, viremia/RNAemia, and biomarkers relevant to dengue in humans. This improved dengue macaque model may be crucial for early assessment of efficacy and safety of future dengue vaccines.

Toward Systematic Screening for Persistent Hepatitis E Virus Infections in Transplant Patients.

BACKGROUND: Persistent hepatitis E virus genotype 3 (HEV G3) infections affect solid organ transplant (SOT) recipients and hematopoietic stem cell transplant (HSCT) recipients, but the burden in these cohorts in the United Kingdom is unknown. We established an audit to determine the point prevalence of HEV viremia in SOT and HSCT patients in the United Kingdom and compare different testing approaches to inform screening strategies. METHODS: Between January 5, 2016, and September 21, 2016, 3044 patients undergoing therapeutic drug monitoring at a single transplant center were screened for HEV ribonucleic acid (RNA) in minipools. A total of 2822 patients who could be characterized included 2419 SOT patients, 144 HSCT patients and 259 patients with no available transplant history. HEV RNA-positive samples were characterized by serology and genomic phylogeny. HEV antigen (HEV-Ag) testing was performed on RNA-positive samples, 420 RNA-negative samples and 176 RNA-negative blood donor samples. RESULTS: Nineteen of 2822 patients were viremic with G3 HEV giving a prevalence of 0.67%. The median alanine aminotransferase was significantly higher in the HEV viremic patients (P < 0.0001); however, 2 viremic patients had an alanine aminotransferase value within the normal range at the time of screening. The HEV-Ag assay identified 18/19 viremic patients and all those patients with proven viremia longer than 4 weeks. CONCLUSIONS: Transplant recipients in the United Kingdom are at a low but significant risk of HEV infection. HEV-Ag detection could be an alternative to RNA detection where the goal is to identify established persistent HEV infection, particularly where expertise, facilities, or cost prohibit RNA testing.

Prospective Assessment of Adenovirus Infection in Pediatric Kidney Transplant Recipients.

BACKGROUND: Adenovirus infection is associated with graft dysfunction and graft loss in pediatric cardiac, lung, and liver transplants in prior retrospective studies, but data in pediatric kidney transplant recipients is limited. METHODS: We conducted a prospective single-center cohort study of 75 consecutive pediatric kidney transplant recipients who underwent monthly screening for adenovirus viremia and symptom assessment for 2 years posttransplant. RESULTS: Adenovirus viremia was detected in 11 (14.7%) patients at a median onset of 173 days (interquartile range, 109-310 days) posttransplant, 6 (8%) had asymptomatic viremia, and 5 (6.7%) had symptomatic disease (2 with hematuria and 3 with an acute febrile respiratory illness). Viremic patients did not differ from nonviremic patients in age, immunosuppression management, or cytomegalovirus or Epstein-Barr virus serostatus, but were more likely to develop cytomegalovirus viremia during the first 2 years posttransplant. No patient had an increase in creatinine from baseline during the time of adenovirus viremia. In a Cox proportional hazards regression, subclinical adenovirus viremia was not associated with a faster time to a 30% decline in estimated glomerular filtration rate. CONCLUSIONS: Adenovirus infection is common among pediatric kidney transplant recipients and frequently causes symptomatic disease; however, symptoms are often mild and are not associated with a decline in graft function. Routine monitoring for adenovirus viremia in pediatric kidney transplant recipients may not be warranted.

Replication and Excretion of the Live Attenuated Tetravalent Dengue Vaccine CYD-TDV in a Flavivirus-Naive Adult Population: Assessment of Vaccine Viremia and Virus Shedding.

Background: We assessed replication and excretion of the live attenuated tetravalent dengue vaccine (CYD-TDV) into biological fluids following vaccination in dengue-naive adults in Australia. Methods: Vaccinal viremia/shedding was assessed in a subset of participants enrolled in a lot-to-lot consistency study; 95 participants received 3 subcutaneous doses of CYD-TDV from phase 2/3 lots of the vaccine, and 8 received placebo; doses were administered 6 months apart. Quantitative reverse-transcription polymerase chain reaction (qR-PCR) analysis was used to initially detect the yellow fever virus (YFV) core protein gene in the backbone of CYD-TDV in serum, saliva and urine, followed by serotype-specific qRT-PCR analysis of samples positive for YFV by qRT-PCR (lower limit of detection, 5.16 GEq/mL). Results: YFV viremia was detected by qRT-PCR in 69.5% of participants (66 of 95) who received CYD-TDV, mainly 6-14 days after injection 1. The serotypes detected were serotype 4 (in 68.2% of participants [45 of 95]), serotype 3 (in 19.7% [13 of 95]), and serotype 1 (in 12.1% [8 of 95]); serotype 2 was not detected. None of the placebo recipients had vaccinal viremia/shedding. No participants had detectable viral shedding into saliva at levels above the lower limit of quantitation. Two participants had low-level viral shedding (serotype 3) in urine (5.47 and 5.77 GEq/mL). None of the participants with viremia or shedding experienced concomitant fever. Conclusions: Low-level vaccinal viremia may occur following vaccination with CYD-TDV, but this is not associated with any symptom or adverse event. Clinical Trials Registration: NCT01134263.

The present and future disease burden of hepatitis C virus infections with today's treatment paradigm - volume 3.

The total number, morbidity and mortality attributed to viraemic hepatitis C virus (HCV) infections change over time making it difficult to compare reported estimates from different years. Models were developed for 15 countries to quantify and characterize the viraemic population and forecast the changes in the infected population and the corresponding disease burden from 2014 to 2030. With the exception of Iceland, Iran, Latvia and Pakistan, the total number of viraemic HCV infections is expected to decline from 2014 to 2030, but the associated morbidity and mortality are expected to increase in all countries except for Japan and South Korea. In the latter two countries, mortality due to an ageing population will drive down prevalence, morbidity and mortality. On the other hand, both countries have already experienced a rapid increase in HCV-related mortality and morbidity. HCV-related morbidity and mortality are projected to increase between 2014 and 2030 in all other countries as result of an ageing HCV-infected population. Thus, although the total number of HCV countries is expected to decline in most countries studied, the associated disease burden is expected to increase. The current treatment paradigm is inadequate if large reductions in HCV-related morbidity and mortality are to be achieved.

Epstein-Barr virus DNAemia in Iranian liver transplant recipients and assessment of its variation in posttransplant lymphproliferative disorder patients by quantitative polymerase chain reaction assay.

OBJECTIVES: Epstein-Barr virus primary infection and/or reactivation may play a major role in the incidence of posttransplant lymphoproliferative disorder in organ recipients. We assessed Epstein-Barr virus viral load in liver transplant patients suspected of having Epstein-Barr virus/ posttransplant lymphoproliferative disorder at specified times after transplant and evaluated the clinical findings and posttransplant complications. MATERIALS AND METHODS: In the 696 patients who underwent liver transplant in this retrospective study, Epstein-Barr virus viral load was examined intermittently in 127 liver transplant recipients who were suspected to have Epstein-Barr virus infection/disease. Sampling was performed during 4 years from July 2009 to May 2013 using real-time polymerase chain reaction assay. Clinical and pathologic data were gathered by reviewing medical records. RESULTS: There were 78 of the 127 suspected patients (61%) who exhibited Epstein-Barr virus DNAemia and 19 patients had posttransplant lymphoproliferative disorder. The median EBV viral load of posttransplant lymphoproliferative disorder patients was significantly higher than unaffected patients. Posttransplant lymphoproliferative disorder was diagnosed clinically in 34 subjects (4.9%). Estimated mortality rate of posttransplant lymphoproliferative disorder patients was 35% during 1.5-year follow-up after transplant. CONCLUSIONS: Monitoring Epstein-Barr virus load may enable detection of Epstein-Barr virus infection/disease in liver transplant patients suspected of having the virus, even several weeks before the onset of any clinical manifestations, especially in pediatric patients who have high incidence and mortality from posttransplant lymphoproliferative disorder.

Defining acceptable epidemiology ranges in donor populations based on the contamination risk of finished plasma-derived products.

BACKGROUND: For a given plasma-derived product, the risk of final product contamination by hepatitis B virus, hepatitis C virus and human immunodeficiency virus depends upon the epidemiology in the donor population, the virus load in a donation, the product yield and the effective virus reduction capacity in manufacturing. STUDY DESIGN AND METHODS: A Monte Carlo simulation model was developed to estimate the risk of virus contamination of a final product resulting from virus contamination of plasma pools for fractionation. The model was run for both source and recovered plasma at various incidence rates for the three viruses to determine virus loads in minipools and fractionation pools resulting from donations with virus levels below test sensitivities. Together with the virus reduction capacity and yield of a theoretical worst case plasma-derived product, the contamination risk in a final vial was calculated. RESULTS: Acceptable upper-bound centre-level incidence rates in the donor population (per donor centre) result in final products with very high margins of virus safety; the largest determinant of these 'Process Limits' is the virus reduction capacity of the manufacturing process. Short donation intervals and long inventory hold periods for source plasma compensates the lower incidence rates typically observed in recovered plasma donors. CONCLUSIONS: The model calculates process limits for epidemiological data at collection centres based on an appropriate margin of virus safety for final products. The model also takes into consideration the impact of different donor/donation management systems for source and recovered plasma on the number of low viraemic donations entering the plasma pool for fractionation.

Spatial modeling of HIV cryptic viremia and 2-LTR formation during raltegravir intensification.

Combination Antiretroviral Therapy (cART) can suppress plasma HIV below the limit of detection in normal assays. Recently reported results suggest that viral replication may continue in some patients, despite undetectable levels in the blood. It has been suggested that the appearance of the circularized episomal HIV DNA artifact 2-LTR following treatment intensification with the integrase inhibitor raltegravir is a marker of ongoing viral replication. Other work has suggested that lymphoid organs may be a site of reduced antiviral penetration and increased viral production. In this study we model the hypothesis that this ongoing replication occurs in lymphoid follicle sanctuary sites and investigate the patterns of 2-LTR formation expected after raltegravir application. Experimental data is used to estimate the reaction and diffusion parameters in the model, and Monte-Carlo simulations are used to explore model behavior subject to variation in these rates. The results suggest that conditions for the formation of an observed transient peak in 2-LTR formation following raltegravir intensification include a sanctuary site diameter larger than 0.2mm, a viral basic reproductive ratio within the site larger than 1, and a total volume of active sanctuary sites above 20mL. Significant levels of uncontrolled replication can occur in the sanctuary sites without measurable changes in the plasma viral load. By contrast, subcritical replication (where the basic reproductive ratio of the virus is less than 1 in all sites) always results in monotonic increases of measured 2-LTR following raltegravir intensification, occurring at levels below the limit of detection.

Population-based assessment of kaposi sarcoma-associated herpesvirus DNA in plasma among Ugandans.

Risk of Kaposi sarcoma (KS) is linked to detection of Kaposi sarcoma-associated herpesvirus (KSHV) DNA in plasma, but little is known about the prevalence and risk factors for plasma KSHV DNA detection among the general population where KS is endemic. Correlates of KSHV plasma detection were investigated in a population-based sample of adult Ugandans (15-59 years) who participated in an HIV/AIDS serobehavioral survey in 2004/2005. KSHV DNA was measured in plasma of 1,080 KSHV seropositive and 356 KSHV seronegative persons using polymerase chain reaction (PCR). KSHV DNA in plasma was detected in 157 (8.7%) persons; of these 149 (95%) were KSHV seropositive and 8 (5%) were seronegative. Detection of KSHV DNA in plasma was significantly associated with male sex (P < 0.001), older age (P = 0.003), residence in a rural versus urban area (P = 0.002), geographic region (P = 0.02), and being KSHV seropositive (13.8% seropositive vs. 2.3% seronegative, P < 0.001). In a multivariable model, KSHV DNA plasma quantity was significantly higher in men (P = 0.002), inversely associated with age (P = 0.05), and residing in an urban area (P = 0.01). In Uganda, KSHV is detected more frequently in the plasma of adult males and residents of rural regions, potentially explaining the increased risk of KS in these subsets of the Ugandan population.

Assessment of immunovirological features in HIV related non-Hodgkin lymphoma patients and their impact on outcome.

BACKGROUND: Despite the era of highly active antiretroviral therapy, non-Hodgkin lymphoma (NHL) remains one of the main causes of death in HIV-infected patients, with a wide variation on the outcome. OBJECTIVES: We investigated immunological status and EBV, HHV8, HIV viral load in a group of HIV-infected patients at diagnosis of NHL to evaluate their prognostic significance. STUDY DESIGN: Eighty-one consecutive HIV+ NHL patients were studied. CD4 and CD8 cell counts, HHV8 DNA, EBV DNA, HIV RNA and HIV DNA were assessed at diagnosis and at 3 months after chemotherapy initiation. Hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) of disease free survival (DFS) and overall survival (OS) were computed according to CD4 and CD8 cell counts, EBV DNA, HIV RNA and HIV DNA. HRs were, thereafter, computed also for continuous variation of CD4, CD8 cell counts and EBV DNA. RESULTS: In the multivariate analysis, CD4<160 and CD8<590 cell/µl and EBV DNA≥300 c/ml were independently associated to DFS (HR=2.98; 95%CI: 1.26-7.03; HR=2.65, 95%CI: 1.13-6.19; HR=4.01; 95%CI: 1.81-8.91) and OS (HR=3.32; 95%CI: 1.41-7.83; HR=4.62, 95%CI: 1.91-11.19; HR=3.11, 95%CI: 1.42-6.80). HRs for DFS and OS decreased continuously with increasing CD4 and CD8 cell counts, while they increased continuously with increasing EBV DNA levels. CONCLUSIONS: The association with survival of low CD4 and CD8 cell counts and detectable EBV viremia, measured at lymphoma's diagnosis, identified three independent prognostic biomarkers that might help in the management of NHL HIV+ patients, offering complementary information in the ascertainment of their outcome.

Mass scale screening of common arboviral infections by an affordable, cost effective RT-PCR method.

OBJECTIVE: To develop a rapid, cost effective RT-PCR method for the mass scale diagnosis of such diseases at the viremia stage to find out the actual disease burden in that area. METHODS: For this purpose, cases with the history of only short febrile illness were considered. Thus 157 samples with the history of dengue/chikungunya like illness and only 58 samples with a history of acute encephalitis syndrome (AES) were selected. RESULTS: Out of 157 samples, 42 and 74 were detected as dengue and chikungunya, respectively and out of 58 AES cases only 23 could be detected as Japanese encephalitis by this RT-PCR method. CONCLUSIONS: This cost effective RT-PCR method can detect the total positive cases that remain undetected by ELISA method. Moreover, this method is capable to detect the viral RNA from patients' sera even after the appearance of IgM antibody at one fifth costs as compared with the other commercially available kits.

The costs of full suppression of plasma HIV RNA in highly antiretroviral-experienced patients.

The aim of antiretroviral treatment is long-term suppression of plasma HIV RNA<50 copies/ml. The DUET, BENCHMRK, and MOTIVATE trials evaluated the efficacy of etravirine, raltegravir, and maraviroc, respectively, versus placebo, each given with an optimized background regimen of nucleoside reverse transcriptase inhibitors, protease inhibitors, and/or enfuvirtide. These trials were conducted in treatment-experienced patients, where complex and expensive drug combinations are typically required. Rates of plasma HIV RNA suppression<50 copies in different treatment groups by week 48 were combined with drug costs to calculate the costs per patient with undetectable viremia. These results were compared with two recent pilot studies of novel triple combination treatment. The average annual per patient cost of antiretrovirals for the active plus optimized background regimen arm versus placebo plus optimized background regimen was US$ 47,324 vs. 38,267 in the DUET Trials, US$ 45,484 vs. 34,585 in BENCHMRK, and US$ 46,633 vs. 36,404 in MOTIVATE. In the three trials, the highest treatment costs were from nucleoside analogs (29-30% of total costs) and enfuvirtide (22-25% of total costs). In the two pilot studies, the total cost of raltegravir/etravirine/darunavir/ritonavir was US$ 32,208, while use of raltegravir/etravirine/maraviroc cost US$ 30,952 per patient-year. The mean cost per patient with HIV RNA<50 copies/ml at week 48 ranged from US$ 62,268 in the etravirine plus optimized background regimen arm of DUET, to US$ 214,141 in the placebo arm of MOTIVATE. In the pilot studies, the cost per patient with HIV RNA<50 copies/ml was US$ 33,204 for raltegravir/etravirine/darunavir/ritonavir and US$ 33,603 for raltegravir/etravirine/maraviroc. In summary, when treating highly treatment-experienced patients, cost-savings could be made by using combinations of newer antiretrovirals in preference to recycled nucleoside analogs and enfuvirtide.

Assessment of bluetongue viraemia in sheep by real-time PCR and correlation with viral infectivity.

Inoculation of embryonated chicken eggs is the standard method for the titration of infectious Bluetongue virus (BTV). Here, six RNA extraction methods coupled with optimised dsRNA denaturation and real-time RT-PCR were evaluated for the quantitation of BTV in blood samples from experimentally infected sheep and results were correlated to infectious virus titres. An exogenous dsRNA internal control (IC) from the closely related Epizootic hemorrhagic disease virus (EHDV) was used to assess the efficiency of BTV genome extraction, dsRNA denaturation, RT, and PCR amplification. Recovery rates of IC and BTV dsRNA copies from extracted blood samples were highly correlated. Adjustment of BTV concentrations according to the IC recovery reduced variation in sample analyses among the different extraction methods and improved the accuracy of BTV quantitation. The EID(50)/ml titre, determined in blood samples from sheep infected experimentally with BTV-1 or BTV-9, correlated highly with the assessed concentration of BTV dsRNA copies. However, this correlation was consistent only during the first 28 days post-infection. The optimised extraction methods and quantitative RT-PCR could be useful for experimental studies of BTV transmission, pathogenesis and vaccine efficacy, or adapted further for the detection and quantitation of EHDV, African horse sickness virus and other dsRNA viruses.

The interplay of sociodemographic factors on virologic suppression among a U.S. outpatient HIV clinic population.

Understanding challenges to virologic suppression is essential to optimizing health outcomes among individuals with HIV. This cross-sectional behavioral assessment was conducted among 514 individuals presenting at an urban U.S. HIV clinic between June and September 2007. The majority of the sample was African American and male, with a mean age of 42 years. Most of the sample was receiving highly active antiretroviral therapy (HAART), and the majority of those had suppressed viral loads (HIV viral loads less than 400 copies per milliliter). By logistic regression analyses, African American/other minorities had 2.9 increased odds, those less than high school degree had 2.3 increased odds, those who were receiving ritonavir-boosted protease inhibitor therapy had 1.4 increased odds, and those who had expressed symptoms indicative of depressive disorders had 2.5 increased odds of having unsuppressed viremia as compared to Caucasians, those with more education, receiving non-nucleoside reverse transcriptase inhibitor-based therapy, and who had minimal depressive symptoms, respectively. These findings signify the importance of individualized interventions to enhance virologic suppression, both based on medication choices and individual characteristics.

Assessment of viremia associated with experimental primary feline herpesvirus infection or presumed herpetic recrudescence in cats.

OBJECTIVE: To detect feline herpesvirus type 1 (FHV-1) in blood of cats undergoing experimental primary herpetic disease or with spontaneous disease presumed to be caused by FHV-1 reactivation. ANIMALS: 6 young specific-pathogen-free (SPF) cats and 34 adult cats from a shelter. PROCEDURES: Conjunctiva and nares of SPF cats were inoculated with FHV-1, and cats were monitored for 21 days. Periodically, blood was collected for CBC, serum biochemical analyses, and detection of FHV-1 DNA via PCR assay. For shelter cats, a conjunctival swab specimen was collected for FHV-1 PCR assay, and blood mononuclear cells were tested via virus isolation (with or without hydrocortisone) and FHV-1 PCR assay. RESULTS: All SPF cats developed clinical and clinicopathologic evidence of upper respiratory tract and ocular disease only. Via PCR assay, FHV-1 DNA was detected in blood of all SPF cats at least once between 2 and 15 days after inoculation. Feline herpesvirus type 1 DNA was detected in conjunctival swabs of 27 shelter cats; 25 had clinical signs of herpetic infection. However, virus was not isolated from mononuclear cell samples of any shelter cat regardless of passage number or whether hydrocortisone was present in the culture medium; FHV-1 DNA was not detected in any mononuclear cell sample collected from shelter cats. CONCLUSIONS AND CLINICAL RELEVANCE: A brief period of viremia occurred in cats undergoing primary herpetic disease but not in cats undergoing presumed recrudescent herpetic disease. Viremia may be important in the pathogenesis of primary herpetic disease but seems unlikely to be associated with recrudescent disease.

Assessment of adenovirus infection in adult lung transplant recipients using molecular surveillance.

BACKGROUND: Little is known about adenovirus infections in adult lung transplant recipients. Because the virus can establish latency, re-activation may be relatively common after transplantation. METHODS: We assessed adenovirus infection in 80 adult lung transplant recipients. Adenovirus polymerase chain reaction (real-time PCR assay; limit of detection approximately 25 copies/ml plasma) was done on plasma samples collected at regular intervals until 1 year post-transplant. RESULTS: Adenovirus DNA was detected in 18 of 80 patients (22.5%) and in 19 of 595 (3.4%) plasma samples up to 12 months post-transplant. Median time to detection of viremia was 134 days post-transplant (range 1 to 370 days). Median viral load was 180 copies/ml plasma (range 50 to 360 copies/ml). Symptoms were evaluated at the time of adenovirus detection: 14 of 18 (78%) patients were asymptomatic; 4 of 18 (22%) patients had otherwise unexplained febrile/flu-like illness that resolved spontaneously. Adenovirus was not found to be a trigger for acute rejection. No detrimental effect on pulmonary function was seen immediately after adenovirus infection. CONCLUSIONS: Adenovirus viremia is common in adult lung transplant recipients. In contrast to findings on adenoviral pneumonitis in lung transplant recipients, isolated episodes of low-level viremia are self-limited and do not trigger acute rejection or a decline in pulmonary function.