Risk of SARS-CoV-2 transmission upon return to work in RNA-positive healthcare workers.

BACKGROUND: Healthcare workers (HCWs) are at risk for coronavirus disease 2019 (COVID-19), and for spreading severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) amongst colleagues and patients. AIM: To study the presence of SARS-CoV-2 RNA and possible onward transmission by HCWs upon return to work after COVID-19, and association with disease severity and development of antibodies over time. METHODS: Unvaccinated HCWs with positive SARS-CoV-2 reverse transcriptase polymerase chain reaction (RT-PCR) were recruited prospectively. Data on symptoms were collected via telephone questionnaires on days 2, 7, 14 and 21 after a positive test. Upon return to work, repeat SARS-CoV-2 RT-PCR was performed and serum was collected. Repeat serum samples were collected at weeks 4, 8, 12 and 16 to determine antibody dynamics over time. Phylogenetic analysis was conducted to investigate possible transmission events originating from HCWs with a positive repeat RT-PCR. FINDINGS: Sixty-one (84.7%) participants with mild/moderate COVID-19 had a repeat SARS-CoV-2 RT-PCR performed upon return to work (median 13 days after symptom onset), of which 30 (49.1%) were positive with a median cycle threshold (Ct) value of 29.2 (IQR 26.9-29.9). All HCWs developed antibodies against SARS-CoV-2. No significant differences in symptomatology and presence of antibodies were found between repeat RT-PCR-positive and -negative HCWs. Eleven direct colleagues of six participants with a repeat RT-PCR Ct value <30 tested positive after the HCW returned to work. Phylogenetic and epidemiologic analysis did not indicate onward transmission through HCWs who were SARS-CoV-2 RNA positive upon return to work. CONCLUSIONS: HCWs regularly return to work with substantial SARS-CoV-2 RNA loads. However, this study found no evidence for subsequent in-hospital transmission.

Retrieval of chronic hepatitis C patients. A manifesto for action to eliminate hepatitis C in the Netherlands: the CELINE project.

Chronic hepatitis C virus (HCV) infection is a global public health issue, which is associated with high rates of morbidity and mortality. The development of direct acting antivirals (DAAs) has transformed treatment: they offer us highly-effective therapy with superior tolerability compared to interferon-containing regimens. In 2016, the World Health Organization (WHO) therefore adopted several ambitious viral hepatitis elimination targets, aiming for a 90% reduction in new infections and a 65% reduction in mortality by 2030. The ultimate goal is to eliminate HCV completely. It is reasonable that these goals may be achieved in the Netherlands due to the low prevalence of chronic HCV, the availability of DAAs, and excellent healthcare infrastructure. This paper describes a national effort to curtail the HCV epidemic in the Netherlands through an HCV retrieval and linkage to care project (CELINE: Hepatitis C Elimination in the Netherlands).

NK cells in self-limited HCV infection exhibit a more extensively differentiated, but not memory-like, repertoire.

Natural killer (NK) cells have long been thought of as a purely innate immune cell population, but increasing reports have described developmental and functional qualities of NK cells that are commonly associated with cells of the adaptive immune system. Of these features, the ability of NK cells to acquire functional qualities associated with immunological memory and continuous differentiation resulting in the formation of specific NK cell repertoires has recently been highlighted in viral infection settings. By making use of a unique cohort of monitored, at-risk intravenous drug users in this study, we were able to dissect the phenotypic and functional parameters associated with NK cell differentiation and NK cell memory in patients 3 years after acute HCV infection and either the subsequent self-clearance or progression to chronicity. We observed increased expression of cytolytic mediators and markers CD56bright and NKp46+ of NK cells in patients with chronic, but not self-limited HCV infection. Patients with a self-limited infection expressed higher levels of differentiation-associated markers CD57 and KIRs, and lower levels of NKG2A. A more extensively differentiated NK cell phenotype is associated with self-clearance in HCV patients, while the NK cells of chronic patients exhibited more naïve and effector NK cell phenotypic and functional characteristics. The identification of these distinct NK cell repertoires may shed light on the role NK cells play in determining the outcome of acute HCV infections, and the underlying immunological defects that lead to chronicity.

Analysis of resistance-associated substitutions in acute hepatitis C virus infection by deep sequencing across six genotypes and three continents.

Several direct-acting antivirals (DAAs) have been approved for the treatment of chronic hepatitis C virus (HCV) infections, opening the door to highly effective interferon-free treatment regimens. Resistance-associated substitutions (RASs) have been reported both in treatment-naïve patients and following treatment with protease (NS3), phosphoprotein (NS5A) and polymerase (NS5B) inhibitors. The prevalence of naturally occurring RASs in untreated HCV-infected individuals has mostly been analysed in those infected with genotype 1 (GT1), in the late phase of infection, and only within limited regions of the genome. Furthermore, the geographic distribution of RASs remains poorly characterized. In this study, we used next-generation sequencing to analyse full-length HCV genomes for the prevalence of RASs in acute HCV infections identified in nine international prospective cohorts. RASs were analysed in 179 participants infected with all six major HCV genotypes (GT1-GT6), and the geographic distribution of RASs was assessed in 107 GT1a and GT3a samples. While RASs were detected at varied frequencies across the three genomic regions, and between genotypes, RASs relevant to multiple DAAs in the leading IFN-free regimens were rarely detected in combination. Low-frequency RASs (<10% of the viral population) were also shown to have a GT-specific distribution. The main RASs with geographic associations were NS3 Q80K in GT1a samples and NS5B N142T in GT3a. These data provide the backdrop for prospective surveillance of RASs during DAA treatment scale-up.

Phylogenetic analysis of full-length, early infection, hepatitis C virus genomes among people with intravenous drug use: the InC3 Study.

Cross-continental phylogenetic analysis is important to understand subtle molecular differences of currently circulating hepatitis C virus (HCV) subtypes. Existence of such differences can be crucial in pursuing a universal hepatitis C vaccine. We characterized molecular epidemiology of early HCV infections identified across nine cohorts [North America (n=4), Australia (n=4) and Europe (n=1)] in the International Collaborative of Incident HIV and Hepatitis C in Injecting Cohorts (InC3 ). One hundred and ninety-two full-length HCV genomes were amplified from plasma of incident infections and subjected to next generation sequencing to establish the largest cross-continental, full-length acute HCV genomic data set available to date. Genomes from the most common subtypes (1a: n=94, 2b: n=15 and 3a: n=68) were used in phylogenetic analysis. Using full genome trees, 78 sequences (44%) were found to lie within 29 phylogenetic clusters/pairs defined on the basis of molecular similarity of consensus sequences. Of these, 26 each had exclusively Australian or North American sequences indicating a strong geographical bias for molecular similarity. On further analysis of behavioural and demographic associations, binary logistic regression analysis showed that older age and non-Caucasian ethnicity were significantly associated with clustering. HCV probably evolves in micro-epidemics within geographically isolated communities.

A molecular epidemiological perspective of rhinovirus types circulating in Amsterdam from 2007 to 2012.

Rhinoviruses (RVs) are frequently detected respiratory viruses that cause mild common cold symptoms, but may also lead to more severe respiratory tract infections. The large number of RV types, classified into species A, B and C, hampers clear insights into the epidemiology and clinical significance of each RV type. The aim of this study was to map the circulation of RV types in the Amsterdam area. RV-positive nasopharyngeal and oropharyngeal samples, collected from 2007 to 2012 in the Academic Medical Centre (Amsterdam, the Netherlands), were typed based on the sequence of the region coding for capsid proteins VP4 and VP2. RV-A, RV-B and RV-C were found in proportions of of 52.4% (334/637), 11.3% (72/637), and 36.2% (231/637), respectively. We detected 129 of the 167 currently classified types. RVs circulated throughout the entire year with a peak in the autumn and a decline in the summer. Some RV types were observed throughout the entire sampling period and others had a more seasonal pattern. Nine RV-A and four RV-B novel provisionally assigned types were identified. This study provides an insight into the molecular epidemiology of RVs in the Amsterdam area. The RVs circulating are diverse and include several provisionally new types.

Risk Factors for Sexual Transmission of Hepatitis C Virus Among Human Immunodeficiency Virus-Infected Men Who Have Sex With Men: A Case-Control Study.

Background. Since 2000, incidence of sexually acquired hepatitis C virus (HCV)-infection has increased among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM). To date, few case-control and cohort studies evaluating HCV transmission risk factors were conducted in this population, and most of these studies were initially designed to study HIV-related risk behavior and characteristics. Methods. From 2009 onwards, HIV-infected MSM with acute HCV infection and controls (HIV-monoinfected MSM) were prospectively included in the MOSAIC (MSM Observational Study of Acute Infection with hepatitis C) study at 5 large HIV outpatient clinics in the Netherlands. Written questionnaires were administered, covering sociodemographics, bloodborne risk factors for HCV infection, sexual behavior, and drug use. Clinical data were acquired through linkage with databases from the Dutch HIV Monitoring Foundation. For this study, determinants of HCV acquisition collected at the inclusion visit were analyzed using logistic regression. Results. Two hundred thirteen HIV-infected MSM (82 MSM with acute HCV infection and 131 MSM without) were included with a median age of 45.7 years (interquartile range [IQR], 41.0-52.2). Receptive unprotected anal intercourse (adjusted odds ratio [aOR], 5.01; 95% confidence interval [CI], 1.63-15.4), sharing sex toys (aOR, 3.62; 95% CI, 1.04-12.5), unprotected fisting (aOR, 2.57; 95% CI, 1.02-6.44), injecting drugs (aOR, 15.62; 95% CI, 1.27-192.6), sharing straws when snorting drugs (aOR, 3.40; 95% CI, 1.39-8.32), lower CD4 cell count (aOR, 1.75 per cubic root; 95% CI, 1.19-2.58), and recent diagnosis of ulcerative sexually transmitted infection (aOR, 4.82; 95% CI, 1.60-14.53) had significant effects on HCV acquisition. Conclusions. In this study, both sexual behavior and biological factors appear to independently increase the risk of HCV acquisition among HIV-infected MSM.

Favourable SVR12 rates with boceprevir or telaprevir triple therapy in HIV/HCV coinfected patients.

BACKGROUND: Recent publications have reported superior efficacy of telaprevir- or boceprevir-based triple therapy over conventional peginterferon-alfa/ribavirin therapy, albeit with varying rates of adverse events and treatment discontinuations in HIV/HCV coinfected patients. Therefore, the aim of this study is to describe the effectiveness of triple therapy in an HIV/HCV coinfection cohort in the Netherlands. METHODS: HIV-infected patients with chronic HCV genotype 1 starting triple therapy including either boceprevir or telaprevir were enrolled, 26% had F3-F4 fibrosis. Data were assessed at Week 4, 8, 12, 24, 48 and SVR12 (i.e. absence of detectable plasma HCV RNA 12 weeks after completion of treatment). Failure was defined as discontinuation of treatment due to virological failure, adverse events or loss to follow-up. RESULTS: A total of 53 HIV/HCV coinfected patients started peginterferon-alfa/ribavirin therapy with either boceprevir (n = 29) or telaprevir (n = 24). SVR12 was achieved in 19 (66%) of the boceprevir-treated and 15 (63%) of the telaprevir-treated patients. Both prior relapse and achievement of a rapid virological response were associated with a higher SVR12 rate. Non- response, breakthrough and relapse occurred in 4, 1 and 5 patients on boceprevir and 3, 2, 2 on telaprevir, respectively. One patient was lost to follow-up and one patient died due to progression of liver failure. Except for these two patients, no treatment discontinuations were observed due to adverse events. CONCLUSION: In HIV/HCV coinfected patients, boceprevir or telaprevir triple therapy was well tolerated and resulted in favourable SVR12 rates comparable with previous publications concerning HCV mono-infected patients.

Factors associated with hepatitis C virus RNA levels in early chronic infection: the InC3 study.

Improved understanding of natural history of hepatitis C virus (HCV) RNA levels in chronic infection provides enhanced insights into immunopathogenesis of HCV and has implications for the clinical management of chronic HCV infection. This study assessed factors associated with HCV RNA levels during early chronic infection in a population with well-defined early chronic HCV infection. Data were from an international collaboration of nine prospective cohorts studying acute HCV infection (InC(3) study). Individuals with persistent HCV and detectable HCV RNA during early chronic infection (one year [±4 months] postinfection) were included. Distribution of HCV RNA levels during early chronic infection was compared by selected host and virological factors. A total of 308 individuals were included. Median HCV RNA levels were significantly higher among males (vs females; 5.15 vs 4.74 log IU/mL; P < 0.01) and among individuals with HIV co-infection (vs no HIV; 5.89 vs 4.86; P = 0.02). In adjusted logistic regression, male sex (vs female, adjusted odds ratio [AOR]: 1.93; 95%CI: 1.01, 3.69), interferon lambda 4 (IFNL4) rs12979860 CC genotype (vs TT/CT; AOR: 2.48; 95%CI: 1.42, 4.35), HIV co-infection (vs no HIV; AOR: 3.27; 95%CI: 1.35, 7.93) and HCV genotype G2 (vs G3; AOR: 5.40; 95%CI: 1.63, 17.84) were independently associated with high HCV RNA levels (>5.6 log IU/mL = 400 000 IU/mL). In conclusion, this study demonstrated that IFNL4 rs12979860 CC genotype, male sex, HIV co-infection and HCV genotype G2 are associated with high HCV RNA levels in early chronic infection. These factors exert their role as early as one year following infection.

BMI, male sex and IL28B genotype associated with persistently high hepatitis C virus RNA levels among chronically infected drug users up to 23 years following seroconversion.

The natural course of serum HCV RNA levels during chronic infection remains unclear. We investigated HCV RNA levels and factors associated with HCV RNA levels for the entire course from HCV seroconversion. We measured HCV RNA levels of 54 HCV seroconverters from the Amsterdam Cohort Studies among drug users at yearly intervals up to 23 years using bDNA (VERSANT 3.0, lower limit of detection 615 IU/mL). Samples below the cut-off of the assay were tested by TMA (Siemens VERSANT, detection limit 5 IU/mL). We used a latent class linear mixed model to examine the HCV RNA patterns and factors associated with HCV RNA levels. The median follow-up time was 10.8 years (IQR 6.5-14.9). We found two distinct HCV RNA patterns characterized by 45/54 cases and 9/54 cases. In multivariable analyses, HCV RNA levels were 0.41 log(10) IU/mL (95% confidence interval (CI) 0.06-0.75) higher for males as compared to females. Individuals with the IL28B CC genotype had 0.40 log(10) IU/mL (95% 0.08-0.73) higher HCV RNA levels than individuals with IL28B CT/TT genotypes. Body mass index (BMI) was associated with higher HCV RNA levels, 0.055 log(10) IU/mL per BMI point (95% CI 0.027-0.083). In this unique study, which examines the HCV RNA patterns over an extended period and following seroconversion, male sex, IL28B CC genotype and BMI were independently associated with higher average HCV RNA levels. These results contribute to defining the natural history of HCV infection and could play an important part in clinical decision-making.

IP-10 in chronic hepatitis C patients treated with high-dose interferon.

INTRODUCTION: Interferon-g-inducible protein-10 (IP-10) serum levels are associated with IL28B genotype and may predict response to interferon÷ribavirin-based therapy in chronic hepatitis C patients. Our aim was to relate IP-10 levels before and during treatment to treatment outcome, viral HCV-RNA kinetics and IL28B genotype. PATIENTS AND METHODS: A cohort of chronic hepatitis C patients was treated with high-dose interferon for six weeks, followed by standard peginterferon÷ ribavirin for 24 or 48 weeks. IP-10 and HCV-RNA levels were frequently determined before, during and after treatment. RESULTS: IP-10 levels increased from log2.56 pg÷ml at baseline to log3.48 pg÷ml at Day 1 and gradually diminished thereafter. IP-10 levels at any time point were not statistically different between patients with or without sustained viral response (SVR). Patients with IL28B CC genotype had significantly lower baseline IP-10 levels (p = 0.019) and a higher increase of IP-10 levels from baseline to Day 1 than patients with IL28B non-CC genotypes (p = 0.015). Patients with HCV-RNA decline ≥ 2.28log10 at Day 1 had significantly lower baseline IP-10 levels (p = 0.016) and a higher increase of IP-10 levels from baseline to Day1 (p = 0.047) than patients with HCV-RNA decline of < 2.28log10 at Day 1. CONCLUSIONS: In patients treated with high induction dose interferon, IP-10 levels at any time point were not predictive for SVR. Low baseline IP-10 levels and a higher increase of IP-10 levels from baseline to Day 1 were associated with IL28B CC genotype and HCV-RNA decline ≥ 2.28log10 at Day 1. This suggests that, in our cohort, for prediction of SVR the added value of IP-10 to IL28B genotype and early viral kinetics is limited.

Evolutionary dynamics of hepatitis C virus NS3 protease domain during and following treatment with narlaprevir, a potent NS3 protease inhibitor.

Narlaprevir, a hepatitis C virus (HCV) NS3/4A serine protease inhibitor, has demonstrated robust antiviral activity in a placebo-controlled phase 1 study. To study evolutionary dynamics of resistant variants, the NS3 protease sequence was clonally analysed in thirty-two HCV genotype 1-infected patients following treatment with narlaprevir. Narlaprevir monotherapy was administered for one week (period 1) followed by narlaprevir/pegylated interferon-alpha-2b combination therapy with or without ritonavir (period 2) during two weeks, interrupted by a washout period of one month. Thereafter, all patients initiated pegylated interferon-alpha-2b/ribavirin combination therapy. Longitudinal clonal analysis was performed in those patients with NS3 mutations. After narlaprevir re-exposure, resistance-associated mutations at position V36, T54, R155 and A156 were detected in five patients in >95% of the clones. Narlaprevir retreatment resulted in a 2.58 and 5.06 log10 IU/mL viral load decline in patients with and without mutations, respectively (P=<0.01). After treatment, resistant variants were replaced with wild-type virus within 2-24 weeks in three patients. However, the R155K mutation was still observed 3.1 years after narlaprevir dosing in two patients in 5% and 45% of the viral population. Resistant variants could be detected early during treatment with narlaprevir. A slower viral load decline was observed in those patients with resistance-associated mutations detectable by direct population sequencing. These mutations disappeared within six months following treatment with the exception of R155K mutation, which persisted in two patients.

Performance evaluation of the new Roche cobas AmpliPrep/cobas TaqMan HCV test, version 2.0, for detection and quantification of hepatitis C virus RNA.

To evaluate the analytical performance and explore the clinical applicability of the new Roche cobas AmpliPrep/cobas TaqMan HCV test, v2.0 (CAP/CTM v2.0), a platform comparison was performed on panels and diagnostic samples with the Roche cobas AmpliPrep/cobas TaqMan HCV test (CAP/CTM v1.0), the Siemens Versant HCV RNA 3.0 branched DNA (bDNA) test, the Abbott m2000 RealTime HCV assay (Realtime assay), and the Siemens Versant HCV transcription-mediated amplification (TMA) test (TMA assay). The analytical performance of the CAP/CTM v2.0 on WHO and Acrometrix panels and clinical specimens of patients infected with HCV genotype 1, 2, 3, 4, 5, or 6 relative to that of the CAP/CTM v1.0 was significantly improved. In a qualitative comparison of the CAP/CTM v2.0 relative to the TMA assay on genotype 1 to 4 samples, the two tests proved to be almost equally sensitive. Response-guided therapy in one of five HCV genotype 4-infected patients previously tested with the CAP/CTM v1.0 would have significantly changed if tested with the CAP/CTM v2.0. In conclusion, the Roche CAP/CTM v2.0 has significantly better performance characteristics than the former CAP/CTM HCV v1.0 and the bDNA assay and performance characteristics comparable to those of the Realtime assay.

Repeated virus identification in the airways of patients with mild and severe asthma during prospective follow-up.

BACKGROUND: Respiratory viruses may persist in the airways of asthmatics between episodes of clinical worsening. We hypothesized that patients with clinically stable, severe asthma exhibit increased and more prolonged viral presence in the airways as compared to mild asthmatics and healthy controls. METHODS: Thirty-five subjects (no cold symptoms >4 weeks) entered a 12-week prospective study using three groups: clinically stable mild asthma (GINA 2) (n = 12, age 34.1 ± 13.4 year), severe asthma (GINA 4) (n = 12, age 49.3 ± 14.8 year) and healthy controls (n = 11, age 37.9 ± 14.2 year). All subjects underwent spirometry and completed a written questionnaire on asthma symptoms at baseline. Nasal and throat swabs, induced sputum samples, exhaled breath condensate and gelatine-filtered expired air were analysed at 0, 6 and 12 weeks by a multiplex real-time PCR assay for 14 respiratory viruses using adequate positive and negative controls. RESULTS: Thirty-two of 525 patient assessments (6%) showed a virus-positive sample. Among the 14 respiratory viruses examined, HRV, adenovirus, respiratory syncytial virus, parainfluenza 3&4, human bocavirus, influenza B and coronavirus were detected. When combining all sampling methods, on average 18% of controls and 30% of mild and severe asthmatics were virus positive, which was not different between the groups (P = 0.34). The longitudinal data showed a changing rather than persistent viral presence over time. CONCLUSION: Patients with clinically stable asthma and healthy controls have similar detection rates of respiratory viruses in samples from nasopharynx, sputum and exhaled air. This indicates that viral presence in the airways of stable (severe) asthmatics varies over time rather than being persistent.

Susceptibility of hepatitis B virus to lamivudine restored by resistance to adefovir.

Serial monotherapy and add-on regimes for treatment of chronic hepatitis B virus (HBV) infection may induce the accumulation of viral resistance mutations in patients, reducing the options for ongoing viral suppression. The induction of antiviral resistance by serial application of polymerase inhibitors does not necessarily imply that the subsequent combined use of the drugs will fail. Some HIV strains resistant to one polymerase inhibitor show increased susceptibility to another polymerase inhibitor. After failure of sequential lamivudine and adefovir monotherapy, two patients with hepatitis B changed to treatment with lamivudine plus adefovir and had renewed suppression of HBV. To study the mutational history of resistant HBV subpopulations in the two patients, a part of the HBV polymerase gene was amplified, cloned, sequenced, and analyzed for the presence of mutations, in sequential plasma samples. In both patients serial monotherapy caused the replacement in all HBV clones of wild-type virus by classical lamivudine resistant mutants (L180M and M204V/I), which were replaced subsequently by adefovir resistant mutants (A181V and N236T). When finally lamivudine was added to adefovir, the A181V adefovir mutation persisted in all clones and lamivudine-related mutations did not reappear. During 18 months of combination therapy, HBV-DNA levels decreased 10,000, respectively, 1,000-fold, despite the earlier resistance to lamivudine and adefovir. Although clinically insufficient, this effect indicates that HBV polymerase resistance mutations may be antagonistic, which is relevant if chronic HBV infection is to be treated by a combination of polymerase inhibitors.

Human parechovirus infections in Dutch children and the association between serotype and disease severity.

BACKGROUND: Human parechoviruses (HPeVs) are members of the family Picornaviridae and are classified into 3 known serotypes: HPeV1, HPeV2, and the recently identified HPeV3. HPeV1 and HPeV2 infections are most commonly associated with mild respiratory or gastrointestinal symptoms and occasionally with severe disease conditions, such as flaccid paralysis and encephalitis. HPeV3 infection has been associated with transient paralysis and neonatal infection and has until now only been reported in Japan and Canada. METHODS: Culture isolates considered to be enterovirus on the basis of cell culture but that were found to be enterovirus negative by 5' untranslated region reverse-transcriptase polymerase chain reaction (5'UTR RT-PCR) during the period December 2000 through January 2005 were selected. Isolates were tested by HPeV 5'UTR RT-PCR and were genotyped by sequencing the VP1 region. Phylogenetic analysis was performed, and the association with clinical symptoms was established. RESULTS: Thirty-seven (12%) of the 303 isolates that tested positive for enterovirus by cell culture were in fact HPeV. The majority of the HPeV-positive isolates (n = 27) could be identified as HPeV1. The remaining 10 isolates, which were grown from samples obtained in 2001, 2002, and 2004, could be typed as the recently identified HPeV3. HPeV was exclusively detected in children aged < 3 years. Children infected with HPeV3 were significantly younger than children infected with HPeV1, and sepsis-like illness and central nervous system involvement were more frequently reported in children infected with HPeV3. CONCLUSIONS: We report HPeV infections in young children during the period of 2000-2005 and show an association between HPeV3 infection and sepsis-like illness and central nervous system involvement in neonates.

Adenovirus infection in paediatric stem cell transplant recipients: increased risk in young children with a delayed immune recovery.

Adenovirus (HAdV) infections are a frequent cause of morbidity and mortality after allogeneic human stem cell transplantation (HSCT). We report a retrospective single-centre study on 328 consecutive paediatric recipients of an allogeneic HSCT. During the first 6 months after HSCT, HAdV infection occurred in 37 children (cumulative incidence 12%). The highest incidence was found in young children up to 5 years of age, transplanted after 1994, with >2 log T-cell depletion of a graft of another than an HLA-genotypically identical related donor (actuarial frequency at 6 months 84%). Persistence of HAdV and spreading of the virus over multiple sites showed a trend towards the development of HAdV disease or death, but did not reach significance. Recovery of immunity after HSCT, that is, serum concentrations of IgM and peripheral blood counts of T cells and subsets, was delayed in children with an HAdV infection compared with noninfected children. In seven out of seven patients with HAdV DNA in serum and decreasing lymphocyte counts, the infection had a fatal course. Manipulation of cellular immunity either by tapering of immunosuppression, infusion of donor lymphocytes or immunotherapy using HAdV-specific T cells should be considered in graft recipients at risk for a severe HAdV infection.

Monitoring response during a randomised controlled trial of escalating interferon dose for chronic hepatitis C infection: predictive value of quantitative and qualitative HCV RNA assays.

BACKGROUND: In chronic hepatitis C infection, raising the interferon dose in initial non-responders may increase the generally poor sustained response rates. Monitoring virological response is essential in this kind of individual patient based approach. Quantitative HCV RNA assays are increasingly used for this purpose. However, their additional value as compared to strictly qualitative HCV RNA assays should be evaluated before they are implemented as a routine measurement, since these assays are more expensive and time consuming than qualitative assays. OBJECTIVES: Goals of this study were (1) to test the hypothesis that increasing interferon dose in initial non-responders results in permanent viral clearance in more patients and (2) evaluation of the predictive value of quantitative versus qualitative HCV RNA assays before and during treatment. STUDY DESIGN: 63 patients were treated in a randomised controlled trial of escalating interferon dose. In the standard treatment group patients received 6 MU alpha-2a thrice weekly for 3 months followed by 3 MU thrice weekly for 3 months. In the experimental group interferon dose was escalated at 6 weeks to 9 MU if HCV RNA was still detectable at 4 weeks. Predictors of response were analyzed at various time points before and during treatment and the predictive value of quantitative HCV RNA measurements was compared to that of qualitative HCV RNA assays. RESULTS: No significant difference in sustained response rate was found between the treatment groups at the end of follow-up. At baseline, the strongest independent predictor for a sustained response was a viral load level below 10(6) copies/ml and age younger than 40 years. During treatment a negative HCV RNA status at week 4 was the strongest predictor of a sustained response. Viral load levels during treatment did not independently predict a sustained response. CONCLUSIONS: While on treatment, qualitative HCV RNA assays should be used to monitor response.

No evidence for an effect of the CCR5 delta32/+ and CCR2b 64I/+ mutations on human immunodeficiency virus (HIV)-1 disease progression among HIV-1-infected injecting drug users.

The relationship between CCR5 and CCR2b genotypes and human immunodeficiency virus (HIV)-1 disease progression was studied among the 108 seroconverters of the Amsterdam cohort of injecting drug users (IDUs). In contrast to earlier studies among homosexual men, no effect on disease progression of the CCR5 Delta32/+ and the CCR2b 64I/+ genotypes was found, when progression to AIDS, death, or a CD4 cell count <200/microL was compared by a Cox proportional hazards model. Furthermore, CD4 cell decline (by a regression model for repeated measurements) and virus load in the first 3 years after seroconversion did not differ between the CCR5 and CCR2b wild type and heterozygous genotypes. A nested matched case-control study also revealed no significant effect of the CCR5 and CCR2b mutations. Immunologic differences between IDUs and homosexual men may account for the observed lack of effect. Alternatively, difference in transmission route or characteristics of the HIV-1 variants that circulate in IDUs could also explain this phenomenon.