Echovirus-4 meningitis outbreak imported from India

Square the Circle: Diversity of Viral Pathogens Causing Neuro-Infectious Diseases

Neuroinfections rank among the top ten leading causes of child mortality globally, even in high-income countries. The crucial determinants for successful treatment lie in the timing and swiftness of diagnosis. Although viruses constitute the majority of infectious neuropathologies, diagnosing and treating viral neuroinfections remains challenging. Despite technological advancements, the etiology of the disease remains undetermined in over half of cases. The identification of the pathogen becomes more difficult when the infection is caused by atypical pathogens or multiple pathogens simultaneously. Furthermore, the modern surge in global passenger traffic has led to an increase in cases of infections caused by pathogens not endemic to local areas. This review aims to systematize and summarize information on neuroinvasive viral pathogens, encompassing their geographic distribution and transmission routes. Emphasis is placed on rare pathogens and cases involving atypical pathogens, aiming to offer a comprehensive and structured catalog of viral agents with neurovirulence potential.

Distribution of species enterovirus B in patients with central nervous system infections in São Paulo State, Brazil

Enteroviruses (EV) are most common cause of central nervous system (CNS) infection, mainly aseptic meningitis. In Brazil, data available concerning the distribution of EV types are scarce. The aim of this study was to describe of types EV in patients with infection of the CNS in São Paulo State. This retrospective study was conducted in clinical samples collected from patients with infections of the CNS from 2004 to 2014. We investigated the presence of EV by virus isolation in cell culture. The samples that showed cytopathic effect in the cell culture were submitted by indirect immunofluorescence assay, reverse transcription polymerase chain reaction and VP1 partial sequencing to identification of EV isolated. A total of 176 EV isolated in cell culture was detected and typed in 14.5% (n = 176/1215) of clinical samples analyzed; corresponding to 71.0% of AM, and 19.3% of encephalitis and meningoencephalitis. Echoviruses (E) were isolated most frequently, with 155 strains (88.1%), Coxsackievirus B (CV-B), with 20 cases (11.4%), CV-A, with 01 case (0.6%). E-6 was the most commonly identified followed in decreasing order by E-30; E-18; CV-B5; E-4; E-11; CV-B2 and E-9; E-7; CV-A9, CV-B1, CV-B3, CV-B4, E-13, E-14, and E-21. EV detected were classified as belonging to the species enterovirus B. EV were detected in all the period of the year with the highest rate in the spring and summer months. Data obtained in this study contribute to the knowledge about EV circulation implicated in CNS infections over a 11-year period in São Paulo State, Brazil.

Aseptic meningitis outbreak associated with echovirus 4 in Northern Europe in 2013-2014

Picornaviruses (family Picornaviridae) are small, nonenveloped, positive-sense, single-stranded RNA viruses. The members of this family are currently classified into 47 genera and 110 species. Of picornaviruses, entero- and parechoviruses are associated with aseptic meningitis. They are transmitted via fecal-oral and respiratory routes, and occasionally, these viruses may cause a brief viremia and gain access to central nervous system (CNS). During the diagnostic screening of entero- and parechovirus types in Finland in year 2013-14, we detected a cluster of echovirus 4 (E4) infections in young adults and adolescents. As E4 is infrequently detected in Finland, we contacted several Northern and Central European laboratories that conduct routine surveillance for enteroviruses and, for those who have had E4 cases, we send a query for E4 sequences and data. Here we report CNS infections caused by E4 in Finland, Sweden, Norway, Denmark, Iceland and Germany in 2013 and 2014, and show that the E4 detected in these countries form a single lineage. In contrast, E4 strains circulating in these countries preceding the year 2013, and those circulating elsewhere in Europe during 2013-2014, formed several independent clusters.

Molecular characterisation of enteroviruses and clinical findings from a cluster of paediatric viral meningitis cases in Tshwane, South Africa 2010-2011

BACKGROUND

Human enteroviruses (HEVs) are the most common viral pathogen associated with paediatric aseptic meningitis. From October 2010 to February 2011 a cluster of HEV-associated meningitis cases was identified in paediatric patients who had presented at two large tertiary hospitals in Pretoria in the Tshwane Metropolitan Area, Gauteng, South Africa (SA).

OBJECTIVES

The aim of this study was to review the clinical features and to characterise the HEV strains associated with this cluster of meningitis cases.

STUDY DESIGN

In this retrospective study HEVs, detected by real time reverse transcription-polymerase chain reaction in acute phase cerebrospinal fluid specimens from 30 patients with aseptic meningitis, were characterised and the clinical presentations of these patients were described.

RESULTS

Fever (83%), headache (70%) and vomiting (67%) were the most prominent symptoms with signs of meningeal irritation recorded in 67% of the patients. There was a neutrophil predominance in the cerebrospinal fluid of 57% of the patients with pleocytosis. Based on partial nucleotide sequence analysis of the HEV viral protein 1 gene, echovirus (E) serotype 4 (E-4) was identified in 80% (24/30) of specimens with E-9 (3/30) and coxsackie virus B5 (1/30) detected less frequently.

CONCLUSION

In this cluster of aseptic meningitis cases E-4 was the predominant strain with E-9, and to a lesser extent other HEVs, identified less frequently.

Molecular identification of enteroviruses associated with aseptic meningitis in children from India

We identified and characterized enteroviruses associated with aseptic meningitis in children between April 2009 and March 2010. Enterovirus RNA was detected in 51 (45.5 %) of 112 CSF samples. Molecular typing by RT-PCR and sequencing of a partial VP1 region revealed the predominance of echovirus (ECV) 32 (n = 20), followed by ECV 11 (n = 10), ECV 13 and ECV 14 (n = 5 each), coxsackievirus (CV) B3 and CV B6 (n = 3 each), CV A2, CV A10 and ECV 30 (n = 1 each). Phylogenetic analysis of ECV 32 showed 0 to 4 % sequence divergence among strains of the present study and 20-23 % from the prototype Puerto Rico strain at the nucleotide level. This is the first report of ECV 32 associated with an aseptic meningitis epidemic and identification of seven different enterovirus serotypes (CV A2, CV A10, CV B3, CV B6, ECV 13, ECV 14 and ECV 32) in meningitis cases from India.

An automated genotyping tool for enteroviruses and noroviruses

BACKGROUND

Molecular techniques are established as routine in virological laboratories and virus typing through (partial) sequence analysis is increasingly common. Quality assurance for the use of typing data requires harmonization of genotype nomenclature, and agreement on target genes, depending on the level of resolution required, and robustness of methods.

OBJECTIVE

To develop and validate web-based open-access typing-tools for enteroviruses and noroviruses.

STUDY DESIGN

An automated web-based typing algorithm was developed, starting with BLAST analysis of the query sequence against a reference set of sequences from viruses in the family Picornaviridae or Caliciviridae. The second step is phylogenetic analysis of the query sequence and a sub-set of the reference sequences, to assign the enterovirus type or norovirus genotype and/or variant, with profile alignment, construction of phylogenetic trees and bootstrap validation. Typing is performed on VP1 sequences of Human enterovirus A to D, and ORF1 and ORF2 sequences of genogroup I and II noroviruses. For validation, we used the tools to automatically type sequences in the RIVM and CDC enterovirus databases and the FBVE norovirus database.

RESULTS

Using the typing-tools, 785(99%) of 795 Enterovirus VP1 sequences, and 8154(98.5%) of 8342 norovirus sequences were typed in accordance with previously used methods. Subtyping into variants was achieved for 4439(78.4%) of 5838 NoV GII.4 sequences.

DISCUSSION AND CONCLUSIONS

The online typing-tools reliably assign genotypes for enteroviruses and noroviruses. The use of phylogenetic methods makes these tools robust to ongoing evolution. This should facilitate standardized genotyping and nomenclature in clinical and public health laboratories, thus supporting inter-laboratory comparisons.