A prospective study of renal transplant recipients reveals an absence of primary JC polyomavirus infections.

BACKGROUND: Both JC polyomavirus (JCPyV) and BK polyomavirus (BKPyV) are acquired at an early age. JCPyV causes progressive multifocal leukoencephalopathy and has been described in association with nephropathy. OBJECTIVES: Urine and plasma samples from renal transplant recipients (RTRs) were examined for JCPyV to determine its involvement in causing infection and disease. STUDY DESIGN: JCPyV testing was performed on 112 RTRs included in a randomised controlled study of steroid-sparing immunosuppressive regimens [1]. Urine and EDTA blood samples were collected pre- and post-transplantation and analysed for JCPyV using real-time PCR and sequencing to determine genotype and viral variation. Donor and recipient IgG antibody status to JCPyV was also determined. RESULTS: Overall, 13.3% of RTRs were positive for JCPyV of which one patient developed viraemia without viruria. JCPyV DNA was detected early following transplantation (defined as five days post transplantation) from recipients with donors that were positive for JCPyV IgG antibodies. No dual cases of JCPyV and BKPyV were observed. One patient sample had sequence duplication in the non-coding control region. CONCLUSIONS: Like BKPyV, JCPyV tends to occur early post transplantation but did not result in sustained viraemia. There was no deterioration of renal function in patients positive for JCPyV. As with other viruses, JCPyV donor serostatus was a risk factor for detection of JCPyV DNA. JCPyV appears to protect individuals from BKPyV infection, as recipients were twice as likely to develop BKPyV with a negative JCPyV donor.

Two cases of possible transmitted drug-resistant HIV: likely HIV superinfection and unmasking of pre-existing resistance.

In the UK, patients undergo HIV viral load and genotype testing before they are prescribed antiretroviral therapy. The genotype test guides clinicians in prescribing antiretroviral therapy with maximum efficacy against the patient's specific viral strain. HIV viral load escape under antiretroviral drug therapy, to which the virus was thought to be genotypically susceptible, is commonly observed in patients with poor adherence. We observed early viral escapes in two-newly diagnosed patients, during antiretroviral treatment, with different sequences compared to their original viral resistance test and who reported excellent adherence to and tolerance of their therapy. HIV superinfection with a new viral strain was identified in a patient with multiple risk factors and co-infections with sexually transmitted infections. The second patient was a case of the emergence of primary resistant virus under drug pressure. Both suppressed their virus promptly after treatment switch.

Early BK polyomavirus (BKV) reactivation in donor kidney is a risk factor for development of BKV-associated nephropathy.

The pathogenesis of BK polyomavirus (BKV) infection and associated nephropathy in renal transplant recipients is not clearly understood. To gain insight, urine and plasma samples were collected from 112 renal transplant recipients before and after transplantation and tested for the presence of BKV by polymerase chain reaction. Detection of BKV infection very early (ie, 5 days) after transplantation was identified as a risk factor for subsequent BKV viremia and BKV-associated nephropathy. Phylogenetic analysis of VP1 sequences with corresponding ethnicity data suggests that reactivation was of donor origin. Thus, early testing of urine samples from renal transplant recipients may identify those at risk for BKV-associated nephropathy.

Different patterns of BK and JC polyomavirus reactivation following renal transplantation.

AIM: Reactivation of latent BK polyomavirus (BKV) infection is relatively common following renal transplantation and BKV-associated nephropathy has emerged as a significant complication. JC polyomavirus (JCV) reactivation is less well studied. The aim of the study was to determine reactivation patterns for these polyomaviruses in renal transplant recipients using an in-house quantitative real-time multiplex PCR assay and IgG serological assays using recombinant BK and JC virus-like particles. METHODS: Retrospective analysis of urine and plasma samples collected from 30 renal transplant patients from February 2004 to May 2005 at Leeds Teaching Hospitals NHS Trust. Samples were collected at 5 days and thereafter at 1, 3, 6 and 12 months post-transplantation. RESULTS: Eight patients (26.7%) were positive for BK viruria; three of these patients submitted plasma samples and two had BK viraemia. Five patients (16.7%) were positive for JC viruria. A corresponding rise in BKV and JCV antibody titres was seen in association with high levels of viruria. CONCLUSIONS: Different patterns of reactivation were observed: BK viruria was detected after 3-6 months, and JC viruria was observed as early as 5 days post-transplantation. One patient had biopsy-proven BKV nephropathy. No dual infections were seen. In order to ensure better graft survival, early diagnosis of these polyomaviruses is desirable.

Diagnostic accuracy and analytical sensitivity of IDEIA Norovirus assay for routine screening of human norovirus.

Noroviruses (NoVs) are recognized as the leading cause of epidemic and sporadic acute gastroenteritis. Early detection of NoV is crucial to control the spread of the disease. In this study, we evaluated the diagnostic accuracy, analytical sensitivity, and analytical reactivity of the IDEIA Norovirus assay (an enzyme immunoassay [EIA]) in a prospective and retrospective study design. A total of 557 prospectively collected fecal samples and a panel of 97 archived fecal samples, including 21 different GI and GII genotypes, were tested by conventional reverse transcription-PCR (RT-PCR)/bidirectional sequencing, real-time RT-PCR, and electron microscopy. The sensitivity and specificity of the EIA were 57.6% and 91.9%, respectively. The sensitivity for detecting NoV in fecal samples from outbreaks improved from 44.1% when three samples were tested to 76.9% when five samples per outbreak were tested. The EIA was able to detect strains from 7 GI and 11 GII genotypes. The analytical sensitivity of the EIA was 3.1 x 10(6) and 1.6 x 10(7) virus particles g(-1) of fecal sample for NoV GI and GII strains, respectively. Most GII samples positive by EIA had a threshold cycle (C(T)) of <26.5, and 50% of the GII samples negative by EIA had a C(T) of >25.6, suggesting that, although strains from genotypes GI.8, GII.10, and GII.16 were not detected, the low sensitivity of the EIA is primarily caused by low virus concentration. In conclusion, the current EIA may be of use as a rapid screening test during a norovirus outbreak investigation when multiple fecal samples are available; however, sporadic samples should be tested by molecular methods.

Planning for the healthcare burden of hepatitis C infection: Hepatitis C genotypes identified in England, 2002-2007.

BACKGROUND: Identification of HCV genotype is a prerequisite for anti-viral treatment in England. Treatment length and sustained virological response rates vary by genotype. Therefore knowledge of circulating HCV genotypes is important for health-care providers. OBJECTIVES: To describe the HCV genotypes identified in English laboratories and to investigate changes over time; sub-analysis of young adults (15-24 years) to provide information on recently circulating genotypes. STUDY DESIGN: Data from the national reference laboratory and 19 English laboratories participating in the sentinel surveillance of hepatitis testing study were analysed. Multinomial regression was used to investigate trends in genotypes identified between 2002 and 2007. RESULTS: HCV genotypes were available for 18,031 individuals. The majority (89%) of people were genotypes 1 and 3; 3a was the single largest subtype. Half of people born between 1960 and 1989 were genotype 3a and the majority of South Asian people were genotype 3a. People born pre-1940 were nine times more likely to have genotype 1b than 3a. The proportion of 1b infections, relative to 3a, declined over time, but, after adjusting for birth cohort, this effect disappeared. There was no evidence of a relative change in 1a infections. CONCLUSIONS: This is the largest study of genotypes identified in England to date. Changes in genotypes over time were due to decreased genotyping of older individuals. As the population ages, the proportion of more difficult to treat genotypes may decline, leading to possible cost-savings for health-care providers, with a higher chance of achieving sustained virological response.

Monitoring HIV testing in diverse healthcare settings: results from a sentinel surveillance pilot study.

OBJECTIVES: To assess the feasibility and utility of sentinel laboratory surveillance of HIV testing as a tool for understanding patterns and trends in HIV testing in a range of healthcare services. METHODS: Data on all anti-HIV antibody tests carried out by the Leeds Teaching Hospital Trust laboratory over a 12-month period were collated and analysed by demographic information and place of test. Individuals who tested positive were matched to the national database of HIV diagnoses to identify the proportion newly diagnosed with HIV. RESULTS: 41,013 individuals over 1 year of age were tested at least once for HIV during the study period, of whom 0.8% (n=312) were positive. The majority of individuals (77%) were tested in a genitourinary medicine (GUM) clinic or as part of antenatal care, while routine testing of people undergoing haemodialysis, fertility treatment or occupational health screening accounted for a further 13% of those tested. Few individuals (<4%) were tested in general practice. Of the 312 people testing positive, 286 could be matched to the HIV national database and 173/286 (60%) were identified as newly diagnosed. CONCLUSIONS: Little HIV testing is currently performed outside GUM and antenatal settings. Monitoring of HIV testing is essential given new guidelines recommending the expansion of testing in a wide range of settings. Sentinel laboratory surveillance can provide useful demographic data on people tested for HIV and can assess trends in testing over time. Data on HIV testing could be incorporated into existing hepatitis sentinel surveillance, allowing rapid scale-up of this surveillance scheme with minimal effort.

Diversity of noroviruses cocirculating in the north of England from 1998 to 2001.

A study was undertaken to investigate the diversity of noroviruses (NVs) in fecal samples from patients from 529 outbreaks and 141 sporadic cases of gastroenteritis in the North of England from September 1998 to August 2001. NV strains were detected by electron microscopy and characterized by a combination of the Grimsby virus antigen enzyme-linked immunosorbent assay, reverse transcriptase PCR, the heteroduplex mobility assay, and DNA sequencing. Twenty-one distinct NV strains, including several novel or variant strains not seen previously, were found circulating in the population studied. Genogroup II NVs were responsible for 83% of the outbreaks. Several strains cocirculated at any one time. The Bristol (Grimsby/Lordsdale) and Hawaii (Girlington) genotypes were the most prevalent among the NVs identified, detected in 49 and 20% of the outbreaks, respectively. A limited number of other genogroup II and I strains were cocirculating. The virus populations detected in hospitals and nursing homes were distinct from those found in community-based outbreaks. Outbreaks in hospitals and nursing homes were more likely to be caused by genogroup II strain Grimsby or Girlington (P < 0.0001) than by other genogroup II or I strains.

Expression and antigenic characterization of the major capsid proteins of human polyomaviruses BK and JC in Saccharomyces cerevisiae.

BK and JC viruses are ubiquitous human polyomaviruses that are associated with post-transplant interstitial nephritis (BK virus) and progressive multifocal leucoencephalopathy (JC virus). The use of a yeast system to express the major capsid protein (VP1) of two antigenic variants of BKV (strains SB and AS) and JCV is described. VP1s of AS and JCV expressed in Saccharomyces cerevisiae produced proteins of expected molecular weight as determined by gel electrophoresis whereas that of SB appeared to be lower than anticipated. However, all VP1s self-assembled into virus-like particles (VLP) retaining sialic acid-binding and antigenic properties of native virions. This method is highly efficient for producing recombinant proteins and therefore provides an alternative to the baculovirus system.