- Prevalence of tick-borne viruses in Ixodes ricinus assessed by high-throughput real-time PCR. [Journal Article]
- PDPathog Dis 2018 Nov 13
- Ticks are one of the principal arthropod vectors of human and animal infectious diseases. Whereas the prevalence of tick-borne encephalitis virus in ticks in Europe is well studied, there is less inf...
Ticks are one of the principal arthropod vectors of human and animal infectious diseases. Whereas the prevalence of tick-borne encephalitis virus in ticks in Europe is well studied, there is less information available on the prevalence of the other tick-borne viruses (TBVs) existing worldwide. The aim of this study was to improve the epidemiological survey tools of TBVs by the development of an efficient high-throughput test to screen a wide range of viruses in ticks.In this study, we developed a new high-throughput virus-detection assay based on parallel real-time PCRs on a microfluidic system, and used it to perform a large scale epidemiological survey screening for the presence of 21 TBVs in 18,135 nymphs of I. ricinus collected from five European countries. This extensive investigation has (i) evaluated the prevalence of four viruses present in the collected ticks, (ii) allowed the identification of viruses in regions where they were previously undetected.In conclusion, we have demonstrated the capabilities of this new screening method that allows the detection of numerous TBVs in a large number of ticks. This tool represents a powerful and rapid system for TBVs surveillance in Europe and could be easily customized to assess viral emergence.
- [Etiology and clinical analysis of central nervous system infection caused by Coxsackievirus B5 in severe hand, foot and mouth disease in Qingdao City, 2013-2014]. [Journal Article]
- ZYZhonghua Yu Fang Yi Xue Za Zhi 2018 Nov 06; 52(11):1168-1172
- Objective: To illuminate the gene characteristics and clinical characterization of Coxsackievirus B5 (CV-B5) strains isolated from patients with sevre hand, foot and mouth disease (HFMD) in Qingdao ...
Objective: To illuminate the gene characteristics and clinical characterization of Coxsackievirus B5 (CV-B5) strains isolated from patients with sevre hand, foot and mouth disease (HFMD) in Qingdao city. Methods: A total of 1 844 patients of HFMD were consecutively admitted to Qingdao Women and Children's Hospital from 2013 to 2014. Information of the study population described above was collected retrospectively. The samples were collected from at least 1 site (throat swab, cerebrospinal fluid), which viral nucleic acid extracted and the entire VP1 gene sequences of CV-B5 isolates were amplified and sequenced, then the homology and phylogeny analysis were conducted by MEGA7.0. The prototype Faulkner strain and other VP1 amino acid sequences were derived from the GenBank database. Results: A total of 8 CV-B5 positive cases were obtained, including 4 males and 4 females; 6 severe hospitalized cases and 2 outpatients. The age of 6 hospitalized patients ranged from 3 to 48 months, with a median of 26 months. For the six inpatients, fever, convulsions vomiting, diarrhea and rash were the main clinical manifestation, and all combined with viral encephalitis. Compared with the prototype strain Faulkner, in the VP1 region,the nucleotide and the amino acid homologies was 77.3%-78.8% and 95.5%-97.0% respectively. Five out of the six severe cases with substitution of serine (S) to asparagine (N) at amino acid site 95 in the VP1 region. The sequences of 8 CV-B5 strains were classified into genogroup D. Conclusion: Hand, foot and mouth disease associated with CV-B5 virus infection can result in nervous system involvement and the main complication was viral encephalitis. The CV-B5 strains associated with severe hand, foot and mouth disease had high nucleotide homology and present a certain regional aggregation.
- EBV-NMDA double positive encephalitis in an immunocompromised patient. [Letter]
- JNJ Neurol Sci 2018 Nov 03; 396:76-77
- Recognition and management of febrile convulsions in children. [Journal Article]
- BJBr J Nurs 2018 Nov 08; 27(20):1156-1162
- Febrile convulsions (FCs) are characterised by convulsions associated with fever in children aged between 6 months and 6 years. FCs are relatively common and affect 3-4% of children in western countr...
Febrile convulsions (FCs) are characterised by convulsions associated with fever in children aged between 6 months and 6 years. FCs are relatively common and affect 3-4% of children in western countries. This is the most common seizure disorder seen in children. The cause of febrile illness in FC is usually benign and most frequently due to acute viral infection. Convulsions secondary to an intracranial infection (e.g. meningitis, encephalitis) or from acute electrolyte imbalance should not be labelled as FCs. The diagnosis is based mainly on clinical history, and further investigations are generally unnecessary; management is largely symptomatic. Prolonged FC may need anticonvulsant medication to stop the seizure. Referral to paediatric neurologists may be considered in cases of complex or recurrent FC or in children where there is a pre-existing neurological disorder. One third of children with a first FC will develop a further FC during subsequent febrile illness; the likelihood increases in presence of other risk factors. This article outlines the presentation, management, investigations and prognosis for FC, and highlights how nurses in different clinical settings can provide education, support and counselling to help families return to normality after the event. An illustrative case study is also included to highlight the challenges faced by health professionals while managing children with this condition.
- Neurologic Alterations Due to Respiratory Virus Infections. [Review]
- FCFront Cell Neurosci 2018; 12:386
- Central Nervous System (CNS) infections are one of the most critical problems in public health, as frequently patients exhibit neurologic sequelae. Usually, CNS pathologies are caused by known neurot...
Central Nervous System (CNS) infections are one of the most critical problems in public health, as frequently patients exhibit neurologic sequelae. Usually, CNS pathologies are caused by known neurotropic viruses such as measles virus (MV), herpes virus and human immunodeficiency virus (HIV), among others. However, nowadays respiratory viruses have placed themselves as relevant agents responsible for CNS pathologies. Among these neuropathological viruses are the human respiratory syncytial virus (hRSV), the influenza virus (IV), the coronavirus (CoV) and the human metapneumovirus (hMPV). These viral agents are leading causes of acute respiratory infections every year affecting mainly children under 5 years old and also the elderly. Up to date, several reports have described the association between respiratory viral infections with neurological symptoms. The most frequent clinical manifestations described in these patients are febrile or afebrile seizures, status epilepticus, encephalopathies and encephalitis. All these viruses have been found in cerebrospinal fluid (CSF), which suggests that all these pathogens, once in the lungs, can spread throughout the body and eventually reach the CNS. The current knowledge about the mechanisms and routes used by these neuro-invasive viruses remains scarce. In this review article, we describe the most recent findings associated to neurologic complications, along with data about the possible invasion routes of these viruses in humans and their various effects on the CNS, as studied in animal models.
- Neurosurgery in viral encephalitis: Application of decompressive craniectomy in medical diseases. [Letter]
- NNeurochirurgie 2018 Nov 08
- R430: A potent inhibitor of DNA and RNA viruses. [Journal Article]
- SRSci Rep 2018 Nov 09; 8(1):16662
- Acyclovir (ACV) is an effective antiviral agent for treating lytic Herpes Simplex virus, type 1 (HSV-1) infections, and it has dramatically reduced the mortality rate of herpes simplex encephalitis. ...
Acyclovir (ACV) is an effective antiviral agent for treating lytic Herpes Simplex virus, type 1 (HSV-1) infections, and it has dramatically reduced the mortality rate of herpes simplex encephalitis. However, HSV-1 resistance to ACV and its derivatives is being increasingly documented, particularly among immunocompromised individuals. The burgeoning drug resistance compels the search for a new generation of more efficacious anti-herpetic drugs. We have previously shown that trans-dihydrolycoricidine (R430), a lycorane-type alkaloid derivative, effectively inhibits HSV-1 infections in cultured cells. We now report that R430 also inhibits ACV-resistant HSV-1 strains, accompanied by global inhibition of viral gene transcription and enrichment of H3K27me3 methylation on viral gene promoters. Furthermore, we demonstrate that R430 prevents HSV-1 reactivation from latency in an ex vivo rodent model. Finally, among a panel of DNA viruses and RNA viruses, R430 inhibited Zika virus with high therapeutic index. Its therapeutic index is comparable to standard antiviral drugs, though it has greater toxicity in non-neuronal cells than in neuronal cells. Synthesis of additional derivatives could enable more efficacious antivirals and the identification of active pharmacophores.
- Structure analysis and antiviral activity of CW-33 analogues against Japanese encephalitis virus. [Journal Article]
- SRSci Rep 2018 Nov 09; 8(1):16595
- Japanese encephalitis virus (JEV) is a member of neurotropic flaviviruses transmitted by mosquito bites, causing severe central nervous system disorders. Current JEV genotype III vaccines have a low ...
Japanese encephalitis virus (JEV) is a member of neurotropic flaviviruses transmitted by mosquito bites, causing severe central nervous system disorders. Current JEV genotype III vaccines have a low protection against genotype I isolates in the risk zone. The lead compound CW-33, ethyl 2-(3',5'-dimethylanilino)-4-oxo-4,5-dihydrofuran-3-carboxylate, demonstrates the antiviral activity against JEV with an IC50 values of 38.5 μM for virus yield reduction (Int J Mol Sci 2016,17: E1386). This study synthesized fourteen CW-33 analogues containing a fluoro atom or one methoxy group at the C-2, C-3, or C-4 of anilino ring, and then evaluated for their antiviral activity and mechanism. Among 6 amalogues, CW-33A (ethyl 2-(2-fluoroanilino)-4-oxo- 4,5-dihydrofuran-3-carboxylate), and CW-33D (ethyl 2-(3-methoxyanilino)-4-oxo- 4,5-dihydrofuran-3-carboxylate exhibited antiviral potentials in viral cytopathic effect (CPE) inhibition. CW-33A significantly suppressed the viral protein expression, genome synthesis and intracellular JEV particle production, showing a higher inhibitory effect on JEV yield than CW-33 and CW-33D. The study demonstrated that a mono-fluoro substitution on at the C-2 anilino ring of CW-33 improved the antiviral activity JEV, revealing the structure-activity relationship for developing novel agents against JEV infection.
- Limited Correlation of Shotgun Metagenomics Following Host Depletion and Routine Diagnostics for Viruses and Bacteria in Low Concentrated Surrogate and Clinical Samples. [Journal Article]
- FCFront Cell Infect Microbiol 2018; 8:375
- The etiologic cause of encephalitis, meningitis or meningo-encephalitis is unknown in up to 70% of cases. Clinical shotgun metagenomics combined with host depletion is a promising technique to identi...
The etiologic cause of encephalitis, meningitis or meningo-encephalitis is unknown in up to 70% of cases. Clinical shotgun metagenomics combined with host depletion is a promising technique to identify infectious etiologies of central nervous system (CNS) infections. We developed a straightforward eukaryotic host nucleic acid depletion method that preserves intact viruses and bacteria for subsequent shotgun metagenomics screening of clinical samples, focusing on cerebrospinal fluid (CSF). A surrogate CSF sample for a CNS infection paradigm was used to evaluate the proposed depletion method consisting of selective host cell lysis, followed by enzymatic degradation of the liberated genomic DNA for final depletion with paramagnetic beads. Extractives were subjected to reverse transcription, followed by whole genome amplification and next generation sequencing. The effectiveness of the host depletion method was demonstrated in surrogate CSF samples spiked with three 1:100 dilutions of Influenza A H3N2 virus (qPCR Ct-values 20.7, 28.8, >42/negative). Compared to the native samples, host depletion increased the amount of the virus subtype reads by factor 7127 and 132, respectively, while in the qPCR negative sample zero vs. 31 (1.4E-4 %) virus subtype reads were detected (native vs. depleted). The workflow was applied to thirteen CSF samples of patients with meningo-/encephalitis (two bacterial, eleven viral etiologies), a serum of an Andes virus infection and a nose swab of a common cold patient. Unlike surrogate samples, host depletion of the thirteen human CSF samples and the nose swab did not result in more reads indicating presence of damaged pathogens due to, e.g., host immune response. Nevertheless, previously diagnosed pathogens in the human CSF samples (six viruses, two bacteria), the serum, and the nose swab (Human rhinovirus A31) were detected in the depleted and/or the native samples. Unbiased evaluation of the taxonomic profiles supported the diagnosed pathogen in two native CSF samples and the native and depleted serum and nose swab, while detecting various contaminations that interfered with pathogen identification at low concentration levels. In summary, damaged pathogens and contaminations complicated analysis and interpretation of clinical shotgun metagenomics data. Still, proper consideration of these issues may enable future application of metagenomics for clinical diagnostics.
New Search Next
- Metagenomic Sequencing From Mosquitoes in China Reveals a Variety of Insect and Human Viruses. [Journal Article]
- FCFront Cell Infect Microbiol 2018; 8:364
- We collected 8,700 mosquitoes in three sites in China, which belonged to seven species. Their viromes were tested using metagenomic sequencing and bioinformatic analysis. The abundant viral sequences...
We collected 8,700 mosquitoes in three sites in China, which belonged to seven species. Their viromes were tested using metagenomic sequencing and bioinformatic analysis. The abundant viral sequences were detected and annotated belonging to more than 50 viral taxonomic families. The results were verified by PCR, followed by phylogenetic analysis. In the present study, we identified partial viral genes of dengue virus (DENV), a novel circovirus (CCV), densovirus (DNV), Japanese encephalitis virus (JEV), and Wuhan mosquito virus (WMV) in mosquitoes. Metagenomic analysis and PCR amplification revealed three DENV sequences, which were as homologous to the NS3 gene of DENV from Singapore isolated in 2005, with at least 91% nucleotide (nt) identity. Seven fragments of JEV encoding structural proteins were identified belonging to genotype I. They all shared high homology with structural protein genes of JEV isolated from Laos in 2009. The production of infectious virus particles of the newly isolated virus YunnanJEV2017-4 increased after passage from the BHK-21 cell line to the Vero cell line. Novel circovirus-related genes were identified and as being related to an unnamed gene of a mosquito circovirus (MCCV) sequence from the USA isolated in 2011, with at least 41% nt identity: this distant relationship suggests that the parent virus might belong to a novel circovirus genus. Additionally, numerous known viruses and some unknown viruses were also detected in mosquitoes from Yunnan province, China, which will be tested for propagation.