Saffold cardiovirus and multiple sclerosis: no evidence for an association.

Saffold cardiovirus, a newly discovered human cardiovirus, has close similarity with Theiler's murine encephalomyelitis virus (TMEV) which can cause a chronic demyelinating encephalomyelitis in mice. In this study, we tested whether Saffold cardiovirus infection of the brain is associated with multiple sclerosis (MS). Autopsy white matter samples from 19 MS and 9 normal brain donors were tested by polymerase chain reaction. All were negative. Paired cerebrospinal fluid and serum samples from 24 MS patients and 27 controls were tested for Saffold cardiovirus-specific oligoclonal bands, two patients and two controls reacted positive. We conclude that an association between Saffold cardiovirus and MS is highly improbable.

Preterm prelabor rupture of membranes (PPROM) is not associated with presence of viral genomes in the amniotic fluid.

BACKGROUND: The role of viral infections in preterm prelabor rupture of the membranes (PPROM) is not established. Studies on the presence of viral genomes in the amniotic fluid (AF) collected in pregnancies complicated by PPROM show contradictory outcomes. OBJECTIVES: To investigate AF samples of PPROM pregnancies for the presence of viral genomes. STUDY DESIGN: AF samples from patients with PPROM were collected during a 4-year (2008-2012) observational study. 174 women were included with selection criteria of singleton pregnancy, PPROM, and maternal age of 18 years and above. PCR was used for detection of human cytomegalovirus (HCMV), herpes simplex virus (HSV), parvovirus B19, human adenoviruses (HAdV), enteroviruses (EV) and human parechovirus (HPeV). The selection of these viral targets was based on literature regarding screening of AF for presence of viral genomes. RESULTS: Only a single sample was positive out of the 174 tested AFs, HCMV DNA was detected. CONCLUSIONS: PPROM is not associated with active viral infections.

Differential susceptibility and response of primary human myeloid BDCA1(+) dendritic cells to infection with different Enteroviruses.

Coxsackie B viruses (CVBs) and echoviruses (EVs) form the Human Enterovirus-B (HEV-B) species within the family Picornaviridae. HEV-B infections are widespread and generally cause mild disease; however, severe infections occur and HEV-B are associated with various chronic diseases such as cardiomyopathy and type 1 diabetes. Dendritic cells (DCs) are the professional antigen-presenting cells of our immune system and initiate and control immune responses to invading pathogens, yet also maintain tolerance to self-antigens. We previously reported that EVs, but not CVBs, can productively infect in vitro generated monocyte-derived DCs. The interactions between HEV-B and human myeloid DCs (mDCs) freshly isolated from blood, however, remain unknown. Here, we studied the susceptibility and responses of BDCA1(+) mDC to HEV-B species and found that these mDC are susceptible to EV, but not CVB infection. Productive EV7 infection resulted in massive, rapid cell death without DC activation. Contrary, EV1 infection, which resulted in lower virus input at the same MOI, resulted in DC activation as observed by production of type I interferon-stimulated genes (ISGs), upregulation of co-stimulatory and co-inhibitory molecules (CD80, CD86, PDL1) and production of IL-6 and TNF-α, with a relative moderate decrease in cell viability. EV1-induced ISG expression depended on virus replication. CVB infection did not affect DC viability and resulted in poor induction of ISGs and CD80 induction in part of the donors. These data show for the first time the interaction between HEV-B species and BDCA1(+) mDCs isolated freshly from blood. Our data indicate that different HEV-B species can influence DC homeostasis in various ways, possibly contributing to HEV-B associated pathology.

A patient with multifocal tabetic arthropathy: a case report and review of literature.

A 55-year-old man presented with a painless destruction of multiple joints and neurologic deficits. He was admitted with a painless pyogenic arthritis of the right ankle. Four years earlier, he had experienced instability of the right knee after an inexplicable, progressive but painless destruction of the joint. Radiographs showed erosive changes at the smaller joints of both hands and the left foot, as well as deformation and destruction of the right foot. Results from both treponemal and nontreponemal serologic test were positive in blood. The Treponema pallidum particle agglutination index was positive in the cerebrospinal fluid. Tabetic arthropathy was diagnosed.Tabetic arthropathy is a manifestation of neurosyphilis. Because syphilis is known as "the great imitator" and tertiary syphilis is rare, recognizing the disease is the biggest challenge for health care providers. Symptoms may mimic any other disease, and many different medical specialists may be faced with these patients, or as Sir William Osler put it: "He who knows syphilis, knows medicine." Initial diagnosis is usually made on serum and cerebrospinal fluid examination. Penicillin is an effective treatment for neurosyphilis to stop progression of neurologic damage, but it does not cure the previously developed tabetic arthropathy. This case is reported to raise awareness of this uncommon but important manifestation of tertiary syphilis. Unfamiliarity with the clinical presentation of tabetic arthropathy may lead to considerable delay in diagnosis.

Outcome of challenge with Coxsackievirus B4 in young mice after maternal infection with the same virus during gestation.

Enteroviral infections go usually unnoticed, even during pregnancy, yet some case histories and mouse experiments indicate that these viruses may be transmitted vertically. More frequently, however, transmission occurs by (fecal) contamination during and shortly after birth. The aim of this study was to investigate the effect of maternal infection in mice (1) on gravidity outcome and (2) on subsequent challenge of the offspring with the same virus. CD1 outbred female mice were infected by the oral route with coxsackievirus B4 strain E2 or mock-infected at days 4, 10, or 17 of gestation. Weight and signs of sickness were noted daily. Pups were infected at day 25 after birth (4 days postweaning). Organs (brain, pancreas, and heart) were analyzed for viral RNA and histopathology. We observed that maternal infection at day 4 or day 17 of gestation had little effect on pregnancy outcome, whereas infection at day 10 affected dams and/or offspring. Infection of pups resulted in severe inflammation of the pancreas, but only when dams were previously infected, especially at day 17. The blood glucose levels were elevated. Because no trace of infection was found at the time of challenge, a role for immunopathology is suggested.

[Virus and evolution]. / Virus en evolutie.

Viruses have long been held to be derailed cellular elements with a parasitic replication cycle: since without a cell there is no virus. However, the explosion in recently acquired molecular data from genome and protein sequences leads to a completely different view: viruses contain sequences which are unique in the biosphere, which is difficult to combine with the idea of cellular origin. Conversely, some cellular sequences appear to be of viral origin, such as the development of DNA as the most important carrier of genetic information. Recent investigations indicate that viruses probably represent a crucial step in the evolution of the cell. This idea is a great step forwards in understanding the evolution of the cell and explains why viruses have continued to exist alongside cell based lifeforms. Viruses, which are often considered only as enemies of their host, therefore ultimately constitute a driving force in evolution.

Comment on "Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome".

Lombardi et al. (Reports, 23 October 2009, p. 585) reported detection of the human gammaretrovirus XMRV in the blood cells of patients with chronic fatigue syndrome (CFS). However, the patient description provided was incomplete. The inclusion of patients from a "CFS outbreak" previously linked with a viral infection, without confirmation in sporadic CFS cases, casts doubt on the role of XMRV in the pathogenesis of CFS.

Detection of enterovirus RNA in peripheral blood mononuclear cells of type 1 diabetic patients beyond the stage of acute infection.

Previous studies have shown that enteroviral RNA can be detected in blood at the onset of type 1 diabetes (T1D). The infection may play a role in triggering T1D and genetic host factors may contribute to this process. We investigated (1) whether enterovirus is present at the onset of T1D in peripheral blood mononuclear cells (PBMC), plasma, throat, or stool, and (2) whether enteroviral presence is linked with HLA-DR type and/or polymorphisms in melanoma differentiation-associated gene 5 (MDA5) and 2'-5' oligoadenylate synthetase 1 (OAS1), factors of antiviral immunity. To this end, PBMC, plasma, throat, and stool samples from 10 T1D patients and 20 unrelated controls were tested for the presence of enteroviruses (RT-PCR), for HLA-DR type, and polymorphisms in MDA5 and OAS1. Enterovirus RNA was detected in PBMC of 4/10 T1D patients, but none of 20 controls. Plasma was positive in 2/10 T1D patients and none of 20 controls, suggesting that enteroviruses found at the onset of T1D are mainly present in PBMC. All throat samples from positive T1D patients were virus-negative and only 1 fecal sample was positive. The negative results for all throat and most stool samples argues against acute infection. Enterovirus presence was linked with HLA-DR4, but not with polymorphisms in MDA5 or OAS1.

Prevalence of xenotropic murine leukaemia virus-related virus in patients with chronic fatigue syndrome in the Netherlands: retrospective analysis of samples from an established cohort.

OBJECTIVE: The presence of the retrovirus xenotropic murine leukaemia virus-related virus (XMRV) has been reported in peripheral blood mononuclear cells of patients with chronic fatigue syndrome. Considering the potentially great medical and social relevance of such a discovery, we investigated whether this finding could be confirmed in an independent European cohort of patients with chronic fatigue syndrome. DESIGN: Analysis of a well defined cohort of patients and matched neighbourhood controls by polymerase chain reaction. SETTING: Certified (ISO 15189) laboratory of clinical virology in a university hospital in the Netherlands. Population Between December 1991 and April 1992, peripheral blood mononuclear cells were isolated from 76 patients and 69 matched neighbourhood controls. In this study we tested cells from 32 patients and 43 controls from whom original cryopreserved phials were still available. MAIN OUTCOME MEASURES: Detection of XMRV in peripheral blood mononuclear cells by real time polymerase chain reaction assay targeting the XMRV integrase gene and/or a nested polymerase chain reaction assay targeting the XMRV gag gene. RESULTS: We detected no XMRV sequences in any of the patients or controls in either of the assays, in which relevant positive and negative isolation controls and polymerase chain reaction controls were included. Spiking experiments showed that we were able to detect at least 10 copies of XMRV sequences per 10(5) peripheral blood mononuclear cells by real time as well as by nested polymerase chain reaction, demonstrating high sensitivity of both assays. CONCLUSIONS: This study failed to show the presence of XMRV in peripheral blood mononuclear cells of patients with chronic fatigue syndrome from a Dutch cohort. These data cast doubt on the claim that XMRV is associated with chronic fatigue syndrome in the majority of patients.

Phagocytosis of enterovirus-infected pancreatic beta-cells triggers innate immune responses in human dendritic cells.

OBJECTIVE: Type 1 diabetes is a chronic endocrine disorder in which enteroviruses, such as coxsackie B viruses and echoviruses, are possible environmental factors that can trigger or accelerate disease. The development or acceleration of type 1 diabetes depends on the balance between autoreactive effector T-cells and regulatory T-cells. This balance is particularly influenced by dendritic cells (DCs). The goal of this study was to investigate the interaction between enterovirus-infected human pancreatic islets and human DCs. RESEARCH DESIGN AND METHODS: In vitro phagocytosis of human or porcine primary islets or Min6 mouse insuloma cells by DCs was investigated by flow cytometry and confocal analysis. Subsequent innate DC responses were monitored by quantitative PCR and Western blotting of interferon-stimulated genes (ISGs). RESULTS: In this study, we show that both mock- and coxsackievirus B3 (CVB3)-infected human and porcine pancreatic islets were efficiently phagocytosed by human monocyte-derived DCs. Phagocytosis of CVB3-infected, but not mock-infected, human and porcine islets resulted in induction of ISGs in DCs, including the retinoic acid-inducible gene (RIG)-I-like helicases (RLHs), RIG-I, and melanoma differentiation-associated gene 5 (Mda5). Studies with murine Min6 insuloma cells, which were also efficiently phagocytosed, revealed that increased ISG expression in DCs upon encountering CVB-infected cells resulted in an antiviral state that protected DCs from subsequent enterovirus infection. The observed innate antiviral responses depended on RNA within the phagocytosed cells, required endosomal acidification, and were type I interferon dependent. CONCLUSIONS: Human DCs can phagocytose enterovirus-infected pancreatic cells and subsequently induce innate antiviral responses, such as induction of RLHs. These responses may have important consequences for immune homeostasis in vivo and may play a role in the etiology of type 1 diabetes.

Saffold virus, a human Theiler's-like cardiovirus, is ubiquitous and causes infection early in life.

The family Picornaviridae contains well-known human pathogens (e.g., poliovirus, coxsackievirus, rhinovirus, and parechovirus). In addition, this family contains a number of viruses that infect animals, including members of the genus Cardiovirus such as Encephalomyocarditis virus (EMCV) and Theiler's murine encephalomyelits virus (TMEV). The latter are important murine pathogens that cause myocarditis, type 1 diabetes and chronic inflammation in the brains, mimicking multiple sclerosis. Recently, a new picornavirus was isolated from humans, named Saffold virus (SAFV). The virus is genetically related to Theiler's virus and classified as a new species in the genus Cardiovirus, which until the discovery of SAFV did not contain human viruses. By analogy with the rodent cardioviruses, SAFV may be a relevant new human pathogen. Thus far, SAFVs have sporadically been detected by molecular techniques in respiratory and fecal specimens, but the epidemiology and clinical significance remained unclear. Here we describe the first cultivated SAFV type 3 (SAFV-3) isolate, its growth characteristics, full-length sequence, and epidemiology. Unlike the previously isolated SAFV-1 and -2 viruses, SAFV-3 showed efficient growth in several cell lines with a clear cytopathic effect. The latter allowed us to conduct a large-scale serological survey by a virus-neutralization assay. This survey showed that infection by SAFV-3 occurs early in life (>75% positive at 24 months) and that the seroprevalence reaches >90% in older children and adults. Neutralizing antibodies were found in serum samples collected in several countries in Europe, Africa, and Asia. In conclusion, this study describes the first cultivated SAFV-3 isolate, its full-length sequence, and epidemiology. SAFV-3 is a highly common and widespread human virus causing infection in early childhood. This finding has important implications for understanding the impact of these ubiquitous viruses and their possible role in acute and/or chronic disease.

Identification of potential recombination breakpoints in human parechoviruses.

Based on a comparison of the phylogeny of two distant regions, evidence has been found for recombination within parechoviruses. However, recombination breakpoints could not be detected in this way. We searched for potential recombination breakpoints in parechovirus by analysis of complete parechovirus sequences, including a newly isolated strain. Bootscan analysis demonstrated that parechoviruses are mosaic viruses build of regions related to corresponding genomic regions of other parechoviruses. With a genetic algorithm for recombination detection, sites for recombination were found. Analysis of partial sequences, as defined by recombination breakpoints, showed phylogenetic segregation between regions.

Breakthrough VZV infection after immunization, presenting as herpes zoster.

An immunocompromized, VZV-vaccinated child had a breakthrough infection with VZV, acquired at a day-care centre during a chickenpox outbreak. Interestingly, the infection manifested as herpes zoster of 1 dermatome. Typing showed wild-type virus, which suggests that exogenous reinfection with a new strain may present as herpes zoster.

Phagocytosis of picornavirus-infected cells induces an RNA-dependent antiviral state in human dendritic cells.

Dendritic cells (DCs) play a central role in instructing antiviral immune responses. DCs, however, can become targeted by different viruses themselves. We recently demonstrated that human DCs can be productively infected with echoviruses (EVs), but not coxsackie B viruses (CVBs), both of which are RNA viruses belonging to the Enterovirus genus of the Picornaviridae family. We now show that phagocytosis of CVB-infected, type I interferon-deficient cells induces an antiviral state in human DCs. Uptake of infected cells increased the expression of the cytoplasmic RNA helicases retinoic acid-inducible gene I and melanoma differentiation-associated gene 5 as well as other interferon-stimulated genes and protected DCs against subsequent infection with EV9. These effects depended on recognition of viral RNA and could be mimicked by exposure to the synthetic double-stranded RNA analogue poly(I:C) but not other Toll-like receptor (TLR) ligands. Blocking endosomal acidification abrogated protection, suggesting a role for TLRs in the acquisition of an antiviral state in DCs. In conclusion, recognition of viral RNA rapidly induces an antiviral state in human DCs. This might provide a mechanism by which DCs protect themselves against viruses when attracted to an environment with ongoing infection.

Echovirus infection causes rapid loss-of-function and cell death in human dendritic cells.

Coxsackie B viruses (CVB) and Echoviruses (EV) form a single species; Human enterovirus B (HeV-B), within the genus Enterovirus. Although HeV-B infections are usually mild or asymptomatic, they can cause serious acute illnesses. In addition, HeV-B infections have been associated with chronic immune disorders, such as type 1 diabetes mellitus and chronic myocarditis/dilated cardiomyopathy. It has therefore been suggested that these viruses may trigger an autoimmune process. Here, we demonstrate that human dendritic cells (DCs), which play an essential role in orchestration of the immune response, are productively infected by EV, but not CVB strains, in vitro. Infection does not result in DC activation or the induction of antiviral immune responses. Instead, EV infection rapidly impedes Toll-like receptor-mediated production of cytokines and upregulation of maturation markers, and ultimately causes loss of DC viability. These results describe for the first time the effect of EV on the function and viability of human DCs and suggest that infection of DCs in vivo can impede regulation of immune responses.

The genotypic inhibitory quotient and the (cumulative) number of mutations predict the response to lopinavir therapy.

For 95 protease inhibitor-experienced HIV-1-infected patients, the genotypic inhibitory quotient (GIQ; trough level/number of mutations) was calculated for lopinavir. Three different sets of mutations showed equal predictive value. However, the use of cumulative numbers of mutations for calculation of the GIQ showed significantly better association with the virological response. Furthermore, the predictive value of the GIQ was no different from that of the number of mutations alone.

The incidence of congenital cytomegalovirus infections in The Netherlands.

Cytomegalovirus (CMV) is one of the most common causes of congenital infection without an effective treatment or an effective vaccine available to date. The emphasis has to be on preventive strategies, which rely on the epidemiological situation. The incidence of congenital CMV infections, however, is not known for The Netherlands. Therefore, a prospective virological study was carried out in a population of 7,524 pregnant women and 7,793 newborns. CMV-specific IgG antibodies were determined in cord blood by ELISA. When CMV antibodies were present, a CMV specific PCR was performed on the throat swab. A positive PCR was confirmed by urine culture. In addition, the seroepidemiology for CMV was investigated in the metropolitan region (Amsterdam and Rotterdam) which has a different ethnic composition. Congenital CMV infection was found in 7 infants (0.9 per 1,000). None had symptoms at birth or during 24 month follow-up. Carriage or CMV was 41%, with a variation between 35% and 100% depending on ethnicity. The ethnic composition in the south-eastern region was different from that in large cities, but similar to that in the rest of the country. The incidence of congenital CMV infections in The Netherlands is the lowest described to date, which does not justify special preventive policies.

Fatigue and job stress as predictors for sickness absence during common infections.

The objective of this study was to investigate the effect of health and work-related factors as predictors of subsequent sickness absence when experiencing common infections (common cold, flu-like illness, and gastroenteritis). Self-administered questionnaire data were used (baseline n = 12,140). To perform the analysis, employees reporting common infections in the final questionnaire were selected. Employees reporting sickness absence due to common infections were compared with a group who stayed at work during an infection. Multivariate survival analysis revealed no significant effects of job demands, decision latitude, or job strain on absence in workers experiencing common infections. Low levels of commitment (risk [RR] 1.22; confidence interval [CI] 1.03-1.44) and low job satisfaction (RR 1.36; CI 1.13-1.164) increased the chance of being absent during a common cold. Also, having a long-standing disease (RR 1.22; CI 1.05-1.41) and fatigue (RR 1.20; CI 1.05-1.37) increased the chance of being absent during a common infection. Having an executive function decreased the chance of being absent. We conclude that absence during a common cold is partly influenced by motivational factors in work, in contrast to more severe common infections which are more health related. Insight in factors related to absenteeism are important as a start for preventive measures to reduce sickness absence.

Role of the inhibitory quotient in HIV therapy.

A systemic review is presented of all studies that have evaluated the inhibitory quotient (IQ). The IQ is defined as the ratio between (trough) drug concentration and level of drug resistance of the HIV isolate. From the studies presented, it can be concluded that for protease inhibitors (PIs) and efavirenz, the phenotypic IQ is associated with virological response. The genotypic IQ (GIQ) for PIs was also demonstrated to be associated with virological response. An intrinsic limitation of the GIQ is that it is only applicable for PIs, of which resistance is based on the cumulative effect of mutations. As the IQ can be modified by adjustment of the drug dosage, it may be of clinical value. Its application in patient care should therefore be further investigated.

Recurrence of febrile seizures in the respiratory season is associated with influenza A.

OBJECTIVES: To investigate the association of viral infections and febrile seizures (FS). STUDY DESIGN: From April 1998 to April 2002, a prospective, population-based study was carried out among general practitioners to assess the incidence of FS in their practices. Data thus obtained were compared with the incidence of common viral infections recorded in a national registry. Poisson regression analysis was performed to investigate whether the season or the type of infection was associated with the variation observed in FS incidence. RESULTS: Throughout the 4-year period, 267 of 303 (88%) of general practitioners in the Dutch province of Friesland participated in the study. The estimated observation period was approximately 160,000 patient-years. We registered 654 cases of FS in 429 children. The estimated incidence of FS was 2.4 in 1000 patient-years. Poisson regression analysis revealed a positive correlation between recurrent FS and influenza A ( P = .01). CONCLUSIONS: Our study suggests a relation between recurrent FS and influenza A. Influenza vaccination should be considered in all children with a history of FS.