Human polyomavirus 9 (HPyV9) was discovered recently in immunocompromised patients and shown to be genetically closely related to B-lymphotropic polyomavirus (LPyV). No serological data are available for HPyV9, but human antibodies against LPyV have been reported previously. To investigate the seroepidemiology of HPyV9 and the sero-cross-reactivity between HPyV9 and LPyV, a capsomer-based IgG ELISA was established using the major capsid protein VP1 of HPyV9 and LPyV. VP1 of an avian polyomavirus was used as control. For HPyV9, a seroprevalence of 47 % was determined in healthy adults and adolescents (n5328) and 20 % in a group of children (n5101). In both groups, the seroreactivities for LPyV were less frequent and the ELISA titres of LPyV were lower. Of the HPyV9-reactive sera, 47 % reacted also with LPyV, and the titres for both PyVs correlated. Sera from African green monkeys, the natural hosts of LPyV, reacted also with both HPyV9 and LPyV, but here the HPyV9 titres were lower. This potential sero-cross-reactivity between HPyV9 and LPyV was confirmed by competition assays, and it was hypothesized that the reactivity of human sera against LPyV may generally be due to cross-reactivity between HPyV9 and LPyV. The HPyV9 seroprevalence of liver transplant recipients and patients with neurological dysfunctions did not differ from that of age-matched controls, but a significantly higher seroprevalence was determined in renal and haematopoietic stem-cell transplant recipients, indicating that certain immunocompromised patient groups may be at a higher risk for primary infection with or for reactivation of HPyV9. INTRODUCTIONHuman polyomavirus 9 (HPyV9) is the most recently identified of the nine human polyomaviruses (PyVs) reported to date, and was first detected in a renal transplant patient (Scuda et al., 2011). Later, the same virus was also found in human skin (Sauvage et al., 2011).PyVs are small, non-enveloped, circular dsDNA viruses. Primary infection with BK virus (BKV) and JC virus (JCV) occurs in childhood and is usually asymptomatic (Moens & Johannessen, 2008). Subsequently, these viruses establish a latent infection. Reactivation can occur in immunocompromised patients and cause serious disease, such as BKVassociated nephropathy or haemorrhagic cystitis (Gardner et al., 1971;Jiang et al., 2009), JCV-associated progressive multifocal leukoencephalopathy (Hou & Major, 2000;Jiang et al., 2009;Padgett et al., 1971) and trichodysplasia spinulosa caused by trichodysplasia spinulosa-associated PyV (Matthews et al., 2011;van der Meijden et al., 2010). PyVs have been shown to transform cells in vitro and to be tumorigenic in small laboratory rodents (Chen et al., 1989;Eddy et al., 1962;Gross, 1953;Stewart, 1953). BKV and JCV have been implicated aetiologically in a number of human cancers, but this issue is still controversial Maginnis & Atwood, 2009;zur Hausen, 2008). Merkel cell PyV (MCPyV) plays a causative role in Merkel cell carcinoma, a rare but aggressive skin cancer Feng et al., 2008).PyV serology has bee...

HBB [2-(α-hydroxybenzyl)-benzimidazole] and guanidine are potent inhibitors of picornavirus replication. Among other evidence, limited cross-resistance and a synergistic effect of both inhibitors suggest similar but not identical mechanisms of antiviral action. Echovirus-9 variants resistant to each of these drugs were characterized and sequenced. Complete resistance to HBB or guanidine was shown to be due to single but different point mutations in the non-structural protein 2C. Protein 2C was expressed as GST fusion and His-tagged proteins for the wild-type and various mutants. Although three mutations were located in or near conserved NTP binding motifs, NTPase activity was not altered in the presence of HBB or guanidine.

The occurrence of 10 pathogens and three fecal indicators was assessed by quantitative PCR in manures of Australian feedlot cattle. Most samples tested positive for one or more pathogens. For the dominant pathogens Campylobacter jejuni, Listeria monocytogenes, Giardia spp., Cryptosporidium spp., and eaeA-positive Escherichia coli, 102 to 107 genome copies g−1 (dry weight) manure were recovered.

Accurate and conservative information about pathogen inactivation rates is needed as the basis for safe manure management on beef cattle feedlots. The survival of indicators and pathogens in faecal pen manure, stockpiled manure and manure compost was measured with autochthonous indicator bacteria (Escherichia coli, Clostridium perfringens, enterococci, total coliforms) and pathogens (Listeria monocytogenes, Campylobacter jejuni) using culture and/or real-time quantitative PCR (qPCR) methods. Additionally, the manures were incubated at 20, 37, 50 and 60 °C in microcosms to quantify the persistence of autochthonous microorganisms and selected process performance surrogates (Clostridium sporogenes, green fluorescent protein-labelled E. coli and L. monocytogenes). Estimated qPCR cell counts indicated that up to four orders of magnitude more target cells were present compared with the culturable counts. Corresponding T(90) estimates were up to sixfold higher. This study demonstrates the benefits of nucleic acid-based quantification of pathogen inactivation in cattle manures and concludes that the concurrent analysis of microorganisms by molecular and culture methods provides complementary value.

Although Chlamydia pneumoniae is an important human pathogen, the antigens eliciting a specific humoral immune response remain elusive. We scrutinized several recombinant chlamydial surface proteins for speciesspecific recognition by a panel of human sera previously tested for the presence of anti-C. pneumoniae and anti-C. trachomatis antibodies by microimmunofluorescence and enzyme-linked immunosorbent assay. The 15-kDa cysteine-rich protein (CrpA), porin-b (PorB), 9-kDa outer membrane protein (OMP3), 60-kDa outer membrane protein (OMP2), and four fragments of the major outer membrane protein (MOMP) representing each variable domain (VD) were overexpressed in Escherichia coli, affinity purified, and employed for Western blot analysis. None of the sera tested contained antibodies recognizing PorB and OMP3 of C. pneumoniae. Sera from C. pneumoniae-immune patients cross-reacted with OMP2 of C. trachomatis, and sera from C. trachomatisimmune patients cross-reacted with CrpA of C. pneumoniae, indicating that some of chlamydial surface molecules share antigenic epitopes. In contrast, the VD2, as well as the VD3, regions of the MOMP of C. pneumoniae were only recognized by C. pneumoniae-positive sera, suggesting the existence of species-specific epitopes. The identification of such epitopes of cell surface molecules provides new insights into C. pneumoniaespecific immune responses and may be of value for the improvement of C. pneumoniae-specific diagnostic assay systems based on defined recombinant antigens.