Comparative analysis of viral shedding in pediatric and adult subjects with central nervous system-associated enterovirus infections from 2013 to 2015 in Switzerland

Key considerations for pathogen surveillance in wastewater

Wastewater surveillance (WWS) has received significant attention as a rapid, sensitive, and cost-effective tool for monitoring various pathogens in a community. WWS is employed to assess the spatial and temporal trends of diseases and identify their early appearances and reappearances, as well as to detect novel and mutated variants. However, the shedding rates of pathogens vary significantly depending on factors such as disease severity, the physiology of affected individuals, and the characteristics of pathogen. Furthermore, pathogens may exhibit differential fate and decay kinetics in the sewerage system. Variable shedding rates and decay kinetics may affect the detection of pathogens in wastewater. This may influence the interpretation of results and the conclusions of WWS studies. When selecting a pathogen for WWS, it is essential to consider it's specific characteristics. If data are not readily available, factors such as fate, decay, and shedding rates should be assessed before conducting surveillance. Alternatively, these factors can be compared to those of similar pathogens for which such data are available.

Molecular epidemiology and characterization of enteroviruses detected in cerebrospinal fluid and respiratory samples in Slovenia, 2014-2023

Enterovirus (EV) infections have various symptoms and severe complications, including death. To determine EV prevalence and EV types in Slovenia, data on over 25 000 EV RNA tests for diagnostics and surveillance from 2014 to 2023 were analyzed. Altogether, 3733 cerebrospinal fluid (CSF) and 21 297 respiratory (sentinel and clinical) samples were tested for EV RNA. EV typing was performed on all residual EV-positive CSF samples and on subset of respiratory specimens. Altogether, 1238 samples tested positive for EV RNA: 238 (6.4%) CSF and 1000 (4.7%) respiratory samples. EV-positive patients were predominantly male (p < 0.001). Many EV-positive CSF samples were from infants under 3 months (33.1%), whereas most EV-positive respiratory samples were from children 1 to 2 years old (49.2%). Echovirus 30 (E-30) was most frequent in CSF (33.0%), followed by CV-B5 (13.8%) and E-6 (13.8%). CV-A6 was most frequent in respiratory samples (16.0%), followed by EV-D68 (7.6%) and CV-A5 (7.4%). EV types in CSF and respiratory samples show diverse dynamics, with some outbreaks indicated. A significant difference was found in the EV detection rate between CSF and respiratory samples by age. Various EV types were characterized, showing that some EV types are more neurotropic or cause more severe infections.

Evaluation of enterovirus concentration, species identification, and cerebrospinal fluid parameters in patients of different ages with aseptic meningitis in São Paulo, Brazil

Human enteroviruses (EV) are the most common cause of aseptic meningitis worldwide. Data on EV viral load in cerebrospinal fluid (CSF) and related epidemiological studies are scarce in Brazil. This study investigated the influence of EV viral load on CSF parameters, as well as identifying the involved species. CSF samples were collected in 2018-2019 from 140 individuals at The Hospital das Clínicas, São Paulo. The EV viral load was determined using real-time quantitative polymerase chain reaction, while EV species were identified by 5'UTR region sequencing. Median viral load was 5.72 log10  copies/mL and did not differ by subjects' age and EV species. Pleocytosis was observed in 94.3% of cases, with the highest white blood cell (WBC) counts in younger individuals. Viral load and WBC count were correlated in children (p = 0.0172). Elevated lactate levels were observed in 60% of cases and correlated with the viral load in preteen-teenagers (p = 0.0120) and adults (p = 0.0184). Most individuals had normal total protein levels (70.7%), with higher in preteen-teenagers and adults (p < 0.0001). By sequencing, 8.2% were identified as EV species A and 91.8% as species B. Age-specific variations in CSF characteristics suggest distinct inflammatory responses in each group.

[A cross-sectional study of enterovirus nucleic acid test with throat swabs for term late neonates during coronavirus disease 2019]

OBJECTIVES

To investigate the positive rate of enterovirus (EV) nucleic acid in throat swabs of term late neonates hospitalized during the coronavirus disease 2019 (COVID-19) epidemic and the clinical characteristics of the neonates.

METHODS

A single-center cross-sectional study was performed on 611 term late infants who were hospitalized in the neonatal center from October 2020 to September 2021. Throat swabs were collected on admission for coxsackie A16 virus/EV71/EV universal nucleic acid testing. According to the results of EV nucleic acid test, the infants were divided into a positive EV nucleic acid group (8 infants) and a negative EV nucleic acid group (603 infants). Clinical features were compared between the two groups.

RESULTS

Among the 611 neonates, 8 tested positive for EV nucleic acid, with a positive rate of 13.1‰, among whom 7 were admitted from May to October. There was a significant difference in the proportion of infants contacting family members with respiratory infection symptoms before disease onset between the positive and negative EV nucleic acid groups (75.0% vs 10.9%, P<0.001). There were no significant differences between the two groups in demographic data, clinical symptoms, and laboratory test results (P>0.05).

CONCLUSIONS

There is a certain proportion of term late infants testing positive for EV nucleic acid in throat swabs during the COVID-19 epidemic, but the proportion is low. The clinical manifestations and laboratory test results of these infants are non-specific. Transmission among family members might be an important cause of neonatal EV infection.

Development of a Universal Cloning System for Reverse Genetics of Human Enteroviruses

Enteroviruses (EVs) have been associated with several human diseases. Due to their continuous emergence and divergence, EV species have generated more than 100 types and recombinant strains, increasing the public health threat caused by them. Hence, an efficient and universal cloning system for reverse genetics (RG) of highly divergent viruses is needed to understand the molecular mechanisms of viral pathology and evolution. In this study, we generated a versatile human EV whole-genome cDNA template by enhancing the template-switching method and designing universal primers capable of simultaneous cloning and rapid amplification of cDNA ends (RACE)-PCR of EVs. Moreover, by devising strategies to overcome limitations of previous cloning methods, we simplified significant cloning steps to be completed within a day. Of note, we successfully verified our efficient universal cloning system enabling RG of a broad range of human EVs, including EV-A (EV-A71), EV-B (CV-B5, ECHO6, and ECHO30), EV-C (CV-A24), and EV-D (EV-D68), with viral titers and phenotypes comparable to those of their wild types. This rapid and straightforward universal EV cloning strategy will help us elucidate molecular characteristics, pathogenesis, and applications of a broad range of EV serotypes for further development of genetic vaccines and delivery tools using various replication systems. IMPORTANCE Due to the broad spread, incidence, and genetic divergence of enteroviruses (EVs), it has been challenging to deal with this virus that causes severe human diseases, including aseptic meningitis, myocarditis, encephalitis, and poliomyelitis. Therefore, an efficient and universal cloning system for the reverse genetics of highly divergent EVs contributes to an understanding of the viral pathology and molecular mechanisms of evolution. We have simplified the important cloning steps, hereby enhancing the template-switching method and designing universal primers, which enable the important cloning steps to be completed in a day. We have also successfully demonstrated recovery of a broad range of human EVs, including EV-A to -D types, using this advanced universal cloning system. This rapid and robust universal EV cloning strategy will aid in elucidating the molecular characteristics, pathogenesis, and applications of a wide range of EVs for further development of genetic vaccines and antiviral screening using various replication systems.

Recent advances in enterovirus A71 pathogenesis: a focus on fatal human enterovirus A71 infection

Enterovirus A71 (EV-A71) is one of the major pathogens responsible for hand, foot, and mouth disease (HFMD). Many HFMD outbreaks have been reported throughout the world in the past decades. Compared with other viruses, EV-A71 infection is more frequently associated with severe neurological complications and even death in children. EV-A71 can also infect adults and cause severe complications and death, although such cases are very uncommon. Although fatal cases of EV-A71 infection have been reported, the underlying mechanisms of EV-A71 infection, especially the mode of viral spread into the central nervous system (CNS) and mechanisms of pulmonary edema, which is considered to be the direct cause of death, have not yet been fully clarified, and more studies are needed. Here, we first summarize the pathological findings in various systems of patients with fatal EV-A71 infections, focussing in detail on gross changes, histopathological examination, tissue distribution of viral antigens and nucleic acids, systemic inflammatory cell infiltration, and tissue distribution of viral receptors and their co-localization with viral antigens. We then present our conclusions about viral dissemination, neuropathogenesis, and the mechanism of pulmonary edema in EV-A71 infection, based on pathological findings.

Diagnostic performance of different specimens in detecting enterovirus A71 in children with hand, foot and mouth disease

Hand, foot and mouth disease (HFMD) is a major public health problem among children in the Asia-Pacific region. The optimal specimen for HFMD virological diagnosis remains unclear. Enterovirus A71 (EV-A71) neutralizing antibody titres detected in paired sera were considered the reference standard for calculating the sensitivity, specificity, positive and negative predictive value of throat swabs, rectal swabs, stool, blood samples and cerebrospinal fluid (CSF) by RT-PCR or ELISA assay. In this study, clinical samples from 276 HFMD patients were collected for analysing the sensitivity of different kind of specimens. Our results showed that stool had the highest sensitivity (88%, 95% CI: 74%-96%) and agreement with the reference standard (91%). The order of diagnostic yield for EV-A71 infection was stool sample ​≥ ​rectal swab ​> ​throat swab ​> ​blood sample ​> ​CSF sample, and using a combination of clinical samples improved sensitivity for enterovirus detection. The sensitivity of ELISA for IgM antibody detection in sterile-site specimens was significantly higher than that of RT-PCR (serum/plasma: 62% vs. 2%, CSF: 47% vs. 0%) (P ​< ​0.002). In conclusion, our results suggest that stool has the highest diagnostic yield for EV-A71-infected HFMD. If stool is unavailable, rectal swabs can be collected to achieve a similar diagnostic yield. Otherwise, throat swabs may be useful in detecting positive samples. Although IgM in blood or CSF is diagnostically accurate, it lacks sensitivity, missing 40%-50% of cases. The higher proportion of severe cases and shorter interval between onset and sampling contributed to the increase in congruency between clinical testing and the serological reference standard.

Epidemiological and etiological characteristics of viral meningitis for hospitalized pediatric patients in Yunnan, China

BACKGROUND

Viral infection is the most common cause of aseptic meningitis. The purpose of this study was to identify the viruses responsible for aseptic meningitis to better understand the clinical presentations of this disease.

METHOD

Between March 2009 and February 2010, we collected 297 cerebrospinal fluid specimens from children with aseptic meningitis admitted to a pediatric hospital in Yunnan (China). Viruses were detected by using "in house" real-time quantitative polymerase chain reaction or reverse-transcription real-time quantitative polymerase chain reaction from these samples. Phylogenetic analyses were conducted using the Molecular Evolutionary Genetic Analysis version 7.0 software, with the neighbor-joining method.

RESULTS

Viral infection was diagnosed in 35 of the 297 children (11.8%). The causative viruses were identified to be enteroviruses in 25 cases (71.4%), varicella-zoster virus in 5 cases (14.3%), herpes simplex virus 1 in 2 cases (5.7%), and herpes simplex virus 2, Epstein-Barr virus, and human herpesvirus 6 in 1 case each (2.9% each). Of the enteroviruses, coxsackievirus B5 was the most frequently detected serotype (10/25 cases; 40.0%) and all coxsackievirus B5 strains belonged to C group.

CONCLUSIONS

In the study, a causative virus was only found in the minority of cases, of them, enteroviruses were the most frequently detected viruses in patients with viral meningitis, followed by varicella-zoster virus and herpes simplex virus. Our findings underscore the need for enhanced surveillance and etiological study of aseptic meningitis.

Detection and Typing of Human Enteroviruses from Clinical Samples by Entire-Capsid Next Generation Sequencing

There are increasing concerns of infections by enteroviruses (EVs) causing severe disease in humans. EV diagnostic laboratory methods show differences in sensitivity and specificity as well as the level of genetic information provided. We examined a detection method for EVs based on next generation sequencing (NGS) analysis of amplicons covering the entire capsid coding region directly synthesized from clinical samples. One hundred and twelve clinical samples from England; previously shown to be positive for EVs, were analyzed. There was high concordance between the results obtained by the new NGS approach and those from the conventional Sanger method used originally with agreement in the serotypes identified in the 83 samples that were typed by both methods. The sensitivity and specificity of the NGS method compared to those of the conventional Sanger sequencing typing assay were 94.74% (95% confidence interval, 73.97% to 99.87%) and 97.85% (92.45% to 99.74%) for Enterovirus A, 93.75% (82.80% to 98.69%) and 89.06% (78.75% to 95.49%) for Enterovirus B, 100% (59.04% to 100%) and 98.10% (93.29% to 99.77%) for Enterovirus C, and 100% (75.29% to 100%) and 100% (96.34% to 100%) for Enterovirus D. The NGS method identified five EVs in previously untyped samples as well as additional viruses in some samples, indicating co-infection. This method can be easily expanded to generate whole-genome EV sequences as we show here for EV-D68. Information from capsid and whole-genome sequences is critical to help identifying the genetic basis for changes in viral properties and establishing accurate spatial-temporal associations between EV strains of public health relevance.

World-Wide Prevalence and Genotype Distribution of Enteroviruses

Enteroviruses (EVs) are highly prevalent viruses world-wide, causing a wide range of diseases in both children and adults. Insight in the global prevalence of EVs is important to define their clinical significance and total disease burden, and assists in making therapeutic decisions. While many studies have been conducted to describe epidemiology of EVs in specific (sub)populations and patient cohorts, little effort has been made to aggregate the available evidence. In the current study, we conducted a search in the PubMed and Embase (Ovid) databases to identify articles reporting EV prevalence and type distribution. We summarized the findings of 153 included studies. We found that EVs are highly prevalent viruses in all continents. Enterovirus B was the most detected species worldwide, while the other species showed continent-specific differences, with Enterovirus C more detected in Africa and Enterovirus A more detected in Asia. Echovirus 30 was by far the most detected type, especially in studies conducted in Europe. EV types in species Enterovirus B-including echovirus 30-were often detected in patient groups with neurological infections and in cerebrospinal fluid, while Enterovirus C types were often found in stool samples.

Recent advances in the understanding of enterovirus A71 infection: a focus on neuropathogenesis

Introduction: Hand, foot, and mouth disease caused by enterovirus A71 (EV-A71) is more frequently associated with neurological complications and deaths compared to other enteroviruses.Areas covered: The authors discuss current understanding of the neuropathogenesis of EV-A71 based on various clinical, human, and animal model studies. The authors discuss the important advancements in virus entry, virus dissemination, and neuroinvasion. The authors highlight the role of host immune system, host genetic factors, viral quasispecies, and heparan sulfate in EV-A71 neuropathogenesis.Expert opinion: Comparison of EV-A71 with EV-D68 and PV shows similarity in primary target sites and dissemination to the central nervous system. More research is needed to understand cellular tropisms, persistence of EV-A71, and other possible invasion routes. EV-A71 infection has varied clinical manifestations which may be attributed to multiple receptors usage. Future development of antivirals and vaccines should target neurotropic enteroviruses. Repurposing drug and immunomodulators used in combination could reduce the severity of EV-A71 infection. Only a few drugs have been tested in clinical trials, and in the absence of antiviral and vaccines (except China), active virus surveillance, good hand hygiene, and physical distancing should be advocated. A better understanding of EV-A71 neuropathogenesis is critical for antiviral and multivalent vaccines development.

Molecular Epidemiology of Enterovirus in Children with Central Nervous System Infections

Limited recent molecular epidemiology data are available for pediatric Central Nervous System (CNS) infections in Europe. The aim of this study was to investigate the molecular epidemiology of enterovirus (EV) involved in CNS infections in children. Cerebrospinal fluid (CSF) from children (0–16 years) with suspected meningitis–encephalitis (ME) who were hospitalized in the largest pediatric hospital of Greece from October 2017 to September 2020 was initially tested for 14 common pathogens using the multiplex PCR FilmArray^® ME Panel (FA-ME). CSF samples positive for EV, as well as pharyngeal swabs and stools of the same children, were further genotyped employing Sanger sequencing. Of the 330 children tested with FA-ME, 75 (22.7%) were positive for EV and 50 different CSF samples were available for genotyping. The median age of children with EV CNS infection was 2 months (IQR: 1–60) and 44/75 (58.7%) of them were male. There was a seasonal distribution of EV CNS infections, with most cases detected between June and September (38/75, 50.7%). EV genotyping was successfully processed in 84/104 samples: CSF (n = 45/50), pharyngeal swabs (n = 15/29) and stools (n = 24/25). Predominant EV genotypes were CV-B5 (16/45, 35.6%), E30 (10/45, 22.2%), E16 (6/45, 13.3%) and E11 (5/45, 11.1%). However, significant phylogenetic differences from previous described isolates were detected. No unusual neurologic manifestations were observed, and all children recovered without obvious acute sequelae. Specific EV circulating genotypes are causing a significant number of pediatric CNS infections. Phylogenetic analysis of these predominant genotypes found genetic differences from already described EV isolates.

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.

A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10-5 ). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.

Non-polio enterovirus infections in children with central nervous system disorders in Shanghai, 2016-2018: Serotypes and clinical characteristics

BACKGROUND

Non-polio enrerovirus causes a wide spectrum of neurologic syndromes. The epidemiological and clinical profiles of non-polio enrerovirus-associated central nervous system infections vary by regions and over year.

OBJECTIVES

This study aimed to understand the prevalence, serotypes and clinical characteristics of enterovirus-associated aseptic meningitis, encephalitis and meningo-encephalitis in children in Shanghai during 2016-2018.

METHODS

We collected the clinical data and the cerebrospinal fluid specimens from the pediatric patients with aseptic meningitis, encephalitis and meningo-encephalitis during 2016-2018. The nested RT-PCR and sequencing were performed to identify enterovirus and serotypes.

RESULTS

A total of 424 patients were included in this study and their non-duplicated cerebrospinal fluid specimens were collected during the acute stage of illness. Based on PCR assay, enterovirus was detected in 272 (64.15 %) patients, of whom, the ratio of male to female subjects was 1.99, and the mean age was 5.71 ± 3.55 years (range: 0.03-16 years). There were 17 serotypes identified. Echovirus 30 (24.63 %), Coxsackievirus A10 (20.96 %), Coxsackievirus A6 (18.01 %) accounted for 63.6 %, followed by Coxsackievirus B5 (7.72 %), Echovirus 6 (5.88 %), and other serotypes (22.8 %). Of the 10 (3.68 %) critically severe patients, all had refractory seizure, 8 required mechanical ventilation, 7 survivors had recurrent attacks of epilepsy and 3 abandoned treatment; Coxsackievirus A10, Echovirus 9, Coxsackievirus A2, Coxsackievirus A6 and Echovirus 6 were identified.

CONCLUSIONS

Non-polio enterovirus is the major pathogen causing aseptic meningitis, encephalitis and meningo-encephalitis in Chinese children and can cause life-threatening encephalitis and severe sequelae.

Enterovirus, parechovirus, adenovirus and herpes virus type 6 viraemia in fever without source

OBJECTIVES

To evaluate the potential associations between fever without a source (FWS) in children and detection of human enterovirus (HEV), human parechovirus (HPeV), adenovirus (AdV) and human herpesvirus type 6 (HHV-6) in the plasma; and to assess whether the detection of viruses in the plasma is associated with a reduced risk of serious bacterial infection (SBI) and antibiotic use.

DESIGN AND SETTING

Between November 2015 and December 2017, this prospective, single-centre, diagnostic study tested the plasma of children <3 years old with FWS. Real-time (reverse-transcription) PCR for HEV, HPeV, AdV and HHV-6 was used in addition to the standardised institutional work-up. A control cohort was also tested for the presence of viruses in their blood.

RESULTS

HEV, HPeV, AdV and HHV-6 were tested for in the plasma of 135 patients of median age 2.4 months old. At least one virus was detected in 47 of 135 (34.8%): HEV in 14.1%, HHV-6 in 11.1%, HPeV in 5.9% and AdV in 5.2%. There was no difference in antibiotic use between patients with or without virus detected, despite a relative risk of 0.2 for an SBI among patients with viraemia. Controls were less frequently viraemic than children with FWS (6.0% vs 34.8%; p<0.001).

CONCLUSIONS

HEV, HPeV, AdV and HHV-6 are frequently detected in the plasma of children with FWS. Antibiotic use was similar between viraemic and non-viraemic patients despite a lower risk of SBI among patients with viraemia. Point-of-care viral PCR testing of plasma might reduce antibiotic use and possibly investigations and admission rates in patients with FWS.

TRIAL REGISTRATION NUMBER

NCT03224026.

Meningitis gone viral: description of the echovirus wave 2013 in Germany

Background

Aseptic meningitis epidemics may pose various health care challenges.

Methods

We describe the German enterovirus meningitis epidemics in the university hospital centers of Düsseldorf, Cologne and Berlin between January 1st and December 31st, 2013 in order to scrutinize clinical differences from other aseptic meningitis cases.

Results

A total of 72 enterovirus (EV-positive) meningitis cases were detected in our multicenter cohort, corresponding to 5.8% of all EV-positive cases which were voluntarily reported within the National Enterovirus surveillance (EVSurv, based on investigation of patients with suspected aseptic meningitis/encephalitis and/or acute flaccid paralysis) by physicians within this period of time. Among these 72 patients, 38 (52.8%) were enterovirus positive and typed as echovirus (18 pediatric and 20 adult cases, median age 18.5 years; echovirus 18 (1), echovirus 2 (1), echovirus 30 (31), echovirus 33 (1), echovirus 9 (4)). At the same time, 45 aseptic meningitis cases in our cohort were excluded to be due to enteroviral infection (EV-negative). Three EV-negative patients were tested positive for varicella zoster virus (VZV) and 1 EV-negative patient for herpes simplex virus 2. Hospitalization was significantly longer in EV-negative cases. Cerebrospinal fluid analysis did not reveal significant differences between the two groups. After discharge, EV-meningitis resulted in significant burden of sick leave in our pediatric cohort as parents had to care for the children at home.

Conclusions

Voluntary syndromic surveillance, such as provided by the EVSurv in our study may be a valuable tool for epidemiological research. Our analyses suggest that EV-positive meningitis predominantly affects younger patients and may be associated with a rather benign clinical course, compared to EV-negative cases.

Establishment of Asia-Pacific Network for Enterovirus Surveillance

Enteroviruses (EV), the major pathogens of hand, foot, and mouth disease (HFMD) and herpangina, affect millions of children each year. Most human enteroviruses cause self-limited infections except polioviruses, enterovirus A71 (EV-A71), enterovirus D68 (EV-D68), and several echoviruses (Echo) and coxsackieviruses (CV). Especially, EV-A71 has repeatedly caused large-scale outbreaks in the Asia-Pacific region since 1997. Some Asian countries have experienced cyclical outbreaks of severe EV-A71 infections and initiated development of EV-A71 vaccines. Five EV-A71 vaccine candidates have been clinically evaluated and three of them were approved for marketing in China. However, none of the China-approved products seek marketing approval in other countries. This situation supports a role for collaboration among Asian countries to facilitate clinical trials and licensure of EV-A71 vaccines. Additionally, enterovirus D68 outbreaks have been reported in the US and Taiwan currently and caused severe complications and deaths. Hence, an Asia-Pacific Network for Enterovirus Surveillance (APNES) has been established to estimate disease burden, understand virus evolution, and facilitate vaccine development through harmonizing laboratory diagnosis and data collection. Founded in 2017, the APNES is comprised of internationally recognized experts in the field of enterovirus in Asian countries working to raise awareness of this potentially fatal and debilitating disease. This article demonstrated the summaries of the first expert meeting, 2017 International Workshop on Enterovirus Surveillance and Vaccine Development, held by APNES in Taipei, Taiwan, March 2017.

Molecular epidemiology of enteroviruses in Cyprus 2008-2017

Enteroviruses (EVs) are associated with a broad spectrum of disease manifestations, including aseptic meningitis, encephalitis, hand, foot and mouth disease, acute flaccid paralysis and acute flaccid myelitis with outbreaks being reported frequently world-wide. The aim of this study was the molecular characterization of all enteroviruses detected in Cyprus in the ten-year period from January 2008 and December 2017 as well as a description of the circulation patterns associated with the most frequently encountered genotypes. For this purpose, serum, cerebrospinal fluid, nasal swab, skin swab and/or stool samples from 2666 patients with a suspected EV infection were analysed between January 2008 and December 2017. Enteroviruses were detected in 295 (11.1%) patients, which were then investigated further for epidemiological analysis by VP1 genotyping. Overall, 24 different enterovirus types belonging to three different species were identified. The predominant species was EV-B (209/295, 71%), followed by species EV-A (77/295, 26.1%). Only one virus belonged to species EV-D, whereas EV-C enteroviruses were not identified at all. The most frequent genotypes identified were echovirus 30 (26.1%), echovirus 6 (14.2%) and coxsackievirus A6 (10.9%). While Echovirus 30 and echovirus 6 frequency was significantly higher in patients older than 3 years of age, the opposite was observed for CV-A16 and EV-A71, which dominated in young children less than 3 years. Importantly, for the current study period a significant increase of previously only sporadically observed EV-A types, such as EV-A71 and CV-A16 was noted. A phylogenetic analysis of EV-A71 showed that the majority of the EV-A71 strains from Cyprus belonged to sub-genogroup C1 and C2, with the exception of one C4 strain that was observed in 2011. The data presented provide a comprehensive picture of enteroviruses circulating in Cyprus over the last decade and will be helpful to clinicians and researchers involved in the treatment, prevention and control of enteroviral infections by helping interpret trends in enteroviral diseases by associating them with circulating serotypes, for studying the association of enteroviruses with clinical manifestations and develop strategies for designing future EV vaccines.

Outbreak of aseptic meningitis caused by echovirus 30 in Kushiro, Japan in 2017

BACKGROUND

Echovirus 30 (E30) is one of the most common causative agents for aseptic meningitis.

OBJECTIVES

In the autumn of 2017, there was an outbreak caused by E30 in Kushiro, Hokkaido, Japan. The aim of this study was to characterize this outbreak.

STUDY DESIGN

Fifty-nine patients were admitted to the Department of Pediatrics, Kushiro Red Cross Hospital (KRCH) with clinical diagnosis of aseptic meningitis. Among those, 36 patients were finally diagnosed as E30-associated aseptic meningitis by the detection of viral RNA using reverse transcription-polymerase chain reaction (RT-PCR) and/or the evidence of more than four-fold rise in neutralizing antibody (NA) titers in the convalescent phase relative to those in the acute phase. We investigated these 36 confirmed cases.

RESULTS

The median age was 6 years (range: 6 months-14 years). The positive signs and symptoms were as follows: fever (100%), headache (94%), vomiting (92%), jolt accentuation (77%), neck stiffness (74%), Kernig sign (29%), and abdominal pain (28%). The median cerebrospinal fluid (CSF) white cell count, neutrophil count, and lymphocyte count were 222/μL (range: 3-1434/μL), 144/μL (range: 1-1269/μL), and 85/μL (range: 2-354/μL), respectively. Although the detected viral genes demonstrated same cluster, they were different from E30 strains observed in Japan between 2010 and 2014.

CONCLUSION

We mainly showed clinical and virological features of the E30-associated aseptic meningitis outbreak that occurred in Kushiro. To prevent further spread of E30 infection, continuous surveillance of enterovirus (EV) circulation and standard precautions are considered essential.

Surveillance of enteroviruses from paediatric patients attended at a tertiary hospital in Catalonia from 2014 to 2017

BACKGROUND

Enterovirus (EV) infections are usually asymptomatic or mild, but symptomatic infections can evolve to severe complications. Outbreaks of EV-A71 and EV-D68 have been recently reported worldwide, sometimes related to severe clinical outcomes.

OBJECTIVE

To describe EV genetic diversity and the clinical outcomes from paediatric patients attended at a tertiary university hospital in Barcelona (Catalonia, Spain) from 2014 to 2017.

STUDY DESIGN

Specimens were collected from paediatric (<17 years old) cases with suspicion of respiratory tract infection or EV infection. EV laboratory-confirmation was performed by specific real-time multiplex RT-PCR assay. Partial viral VP1 protein was sequenced for genetic characterisation by phylogenetic analyses.

RESULTS

A total of 376 (7%) from 5703 cases were EV laboratory-confirmed. Phylogenetic analyses of VP1 (210; 81%) sequences distinguished up to 27 different EV types distributed within EV-A (82; 40%), EV-B (90; 42%), EV-C (5; 2%), and EV-D (33; 15%), in addition to 50 (19%) rhinoviruses. The most predominant were EV-A71 (37; 45%) and EV-D68 (32; 99%). EV-A71 was highly related to neurological complications (25/39, 63%), of which 20/39 were rhombencephalitis, and most EV-D68 (28/32, 88%) were associated with lower respiratory tract infections (LRTI), and exceptionally one (3%) with acute flaccid paralysis.

CONCLUSIONS

EV-A71 and EV-D68 were the most detected EV in respiratory specimens. EV-A71 was highly related to neurological disease and EV-D68 was often associated with LRTI. However, both potential relatedness to neurological diseases makes the monitoring of EV circulation obligatory.

Molecular characteristics of hand, foot, and mouth disease for hospitalized pediatric patients in Yunnan, China

Hand, foot, and mouth disease (HFMD) is a common infectious disease caused by multiple enteroviruses (EVs) in China. To better define the etiologic agents and clinical characteristics of HFMD, we conducted this study in Yunnan, China.In this study, 1280 stool specimens were collected from pediatric patients hospitalized for treatment of HFMD in 2010. EV was detected with nested reverse transcription polymerase chain reaction and directly genotyped by gene sequencing of the viral protein 1 (VP1) region. Phylogenetic analysis was performed based on the VP1 partial gene and the clinical characteristics were analyzed using SPSS Software.Of 1280 specimens, 1115 (87.1%) tested positive for EV. Seventeen different EV serotypes were detected. Coxsackievirus A16 (CA16) was the most frequently detected serotype (615/1115 cases, 55.1%), followed by enterovirus 71 (EV71; 392/1115, 35.2%), CA10 (45/1115, 4.0%), and CA4 (23/1115, 2.1%). Among the 709 severe cases, CA16, EV71, CA10, and CA4 accounted for 48.0%, 42.0%, 3.5%, and 2.3%, respectively. Of the 26 critical cases, 13 were caused by EV71, 9 by CA16, 2 by CA4, and 1 each were the result of CA10 and E9, respectively. All EV71, CA16, CA10, and CA4 isolates were highly homologous to the strains isolated from mainland China, and belonged to the C4a, B1a, G, and C genotypes, respectively.Our study showed that EV71 and CA16 were the main causative agents for severe and critical HFMD, but other serotypes can also cause severe and critical cases.

Large-Scale Survey of Human Enteroviruses in Wastewater Treatment Plants of a Metropolitan Area of Southern Italy

Human enteroviruses (HEVs) occur in high concentrations in wastewater and can contaminate receiving environmental waters, constituting a major cause of acute waterborne disease worldwide. In this study, we investigated the relative abundance, occurrence, and seasonal distribution of polio and other enteroviruses at three wastewater treatment plants (WWTPs) in Naples, Southern Italy, from January 2010 to December 2014. Influent and effluent samples from the three WWTPs were collected monthly. One hundred and sixty-one of the 731 wastewater samples collected (22.0%) before and after water treatment were CPE positive on RD cells; while no samples were positive on L20B cells from any WWTPs. Among the 140 non-polio enterovirus isolated from inlet sewage, 69.3% were Coxsackieviruses type B and 30.7% were Echoviruses. Among these, CVB3 and CVB5 were most prevalent, followed by CVB4 and Echo6. The twenty-one samples tested after treatment contained 6 CVB4, 5 CVB3, 3 Echo11, and 2 Echo6; while other serotypes were isolated less frequently. Data on viral detection in treated effluents of WWTPs confirmed the potential environmental contamination by HEVs and could be useful to establish standards for policies on wastewater management.