An outbreak of nosocomial infection of neonatal aseptic meningitis caused by echovirus 18.

We describe an outbreak of echovirus 18 infection involving 10 patients in our neonatal intensive care unit (an attack rate of 33%). The mean age at the onset of illness was 26.8 days. Eighty percent were preterm infants. All were discharged home without sequelae. There were no differences in gestation age, birth weight, delivery mode, use of antibiotics, and parenteral nutrition between the enterovirus (EV) group and non-EV group, but the rate of breastfeeding was significantly higher in the EV group. Separation care and reinforcement of hand-washing seemed to be effective in preventing further spread of the virus. Visiting policy, hygiene practice, and handling of expressed breastmilk should be reinforced.

An In Vivo Model of Echovirus-Induced Meningitis Defines the Differential Roles of Type I and Type III Interferon Signaling in Central Nervous System Infection.

Echoviruses are among the most common worldwide causes of aseptic meningitis, which can cause long-term sequelae and death, particularly in neonates. However, the mechanisms by which these viruses induce meningeal inflammation are poorly understood, owing at least in part to the lack of in vivo models that recapitulate this aspect of echovirus pathogenesis. Here, we developed an in vivo neonatal mouse model that recapitulates key aspects of echovirus-induced meningitis. We show that expression of the human homologue of the primary echovirus receptor, the neonatal Fc receptor (FcRn), is not sufficient for infection of the brains of neonatal mice. However, ablation of type I, but not III, interferon (IFN) signaling in mice expressing human FcRn permitted high levels of echovirus replication in the brain, with corresponding clinical symptoms, including delayed motor skills and hind-limb weakness. Using this model, we defined the immunological response of the brain to echovirus infection and identified key cytokines, such as granulocyte colony-stimulating factor (G-CSF) and interleukin 6 (IL-6), that were induced by this infection. Lastly, we showed that echoviruses specifically replicate in the leptomeninges, where they induce profound inflammation and cell death. Together, this work establishes an in vivo model of aseptic meningitis associated with echovirus infections that delineates the differential roles of type I and type III IFNs in echovirus-associated neuronal disease and defines the specificity of echoviral infections within the meninges. IMPORTANCE Echoviruses are among the most common worldwide causes of aseptic meningitis, which can cause long-term sequelae or even death. The mechanisms by which echoviruses infect the brain are poorly understood, largely owing to the lack of robust in vivo models that recapitulate this aspect of echovirus pathogenesis. Here, we establish a neonatal mouse model of echovirus-induced aseptic meningitis and show that expression of the human homologue of the FcRn, the primary receptor for echoviruses, and ablation of type I IFN signaling are required to recapitulate echovirus-induced meningitis and clinical disease. These findings provide key insights into the host factors that control echovirus-induced meningitis and a model that could be used to test anti-echovirus therapeutics.

Pathological Characteristics of Echovirus 30 Infection in a Mouse Model.

Echovirus 30 (E30), a member of species B enterovirus, is associated with outbreaks of aseptic meningitis and has become a global health emergency. However, the pathogenesis of E30 remains poorly understood due to the lack of appropriate animal models. In this study, we established a mouse infection model to explore the pathogenicity of E30. The 2-day-old IFNAR-/- mice infected with E30 strain WZ16 showed lethargy and paralysis, and some died. Obvious pathological changes were observed in the skeletal muscle, brain tissue, and other tissues, with the highest viral load in the skeletal muscles. Transcriptome analysis of brain and skeletal muscle tissues from infected mice showed that significant differentially expressed genes were enriched in complement response and neuropathy-related pathways. Using immunofluorescence assay, we found that the viral double-stranded RNA (dsRNA) was detected in the mouse brain region and could infect human glioma (U251) cells. These results indicated that E30 affects the nervous system, and they provide a theoretical basis for understanding its pathogenesis. IMPORTANCE Echovirus 30 (E30) infection causes a wide spectrum of diseases with mild symptoms, such as hand, foot, and mouth disease (HFMD), acute flaccid paralysis, and aseptic meningitis and other diseases, especially one of the most common pathogens causing aseptic meningitis outbreaks. We established a novel mouse model of E30 infection by inoculating neonatal mice with clinical isolates of E30 and observed the pathological changes induced by E30. Using the E30 infection model, we found complement responses and neuropathy-related genes in the mice tissues at the transcriptome level. Moreover, we found that the viral dsRNA localized in the mouse brain and could replicate in human glioma cell line U251 rather than in the neuroblastoma cell line, SK-N-SH.

Pathological Features of Echovirus-11-Associated Brain Damage in Mice Based on RNA-Seq Analysis.

Echovirus 11 (E11) is a neurotropic virus that occasionally causes fatal neurological diseases in infected children. However, the molecular mechanism underlying the disease and pathological spectrum of E11 infection remains unclear. Therefore, we modelled E11 infection in 2-day-old type I interferon receptor knockout (IFNAR-/-) mice, which are susceptible to enteroviruses, with E11, and identified symptoms consistent with the clinical signs observed in human cases. All organs of infected suckling mice were found to show viral replication and pathological changes; the muscle tissue showed the highest viral replication, whereas the brain and muscle tissues showed the most obvious pathological changes. Brain tissues showed oedema and a large number of dead nerve cells; RNA-Seq analysis of the brain and hindlimb muscle tissues revealed differentially expressed genes to be abundantly enriched in immune response-related pathways, with changes in the Guanylate-binding protein (GBP) and MHC class genes, causing aseptic meningitis-related symptoms. Furthermore, human glioma U251 cell was identified as sensitive target cells for E11 infection. Overall, these results provide new insights into the pathogenesis and progress of aseptic meningitis caused by E11.

First Human Cosavirus Detection From Cerebrospinal Fluid in Hospitalized Children With Aseptic Meningitis and Encephalitis in Iran.

OBJECTIVE: Human cosavirus (HCosV) is a newly recognized virus that seems to be partly related to nonpolio flaccid paralysis and acute gastroenteritis in pediatric patients. However, the relationship between HCosV and diseases in humans is unclear. To assess an investigation for the occurrence of HCosV among pediatric patients involved in meningitis and encephalitis, we implemented a real-time quantitative polymerase chain reaction assay for detection and quantification of HCosV in stool specimens. MATERIALS AND METHODS: In this study, a total of 160 cerebrospinal fluid samples from September 2019 to October 2020 were collected from presenting pediatric patients with meningitis and encephalitis in a Karaj hospital, Iran. After viral RNA extraction, the real-time quantitative polymerase chain reaction was performed to amplify the 5'Un-Translated Region region of the HCosV genome and viral load was analyzed. RESULTS: Of the 160 samples tested, the HCosV genomic RNA was detected in 2/160 (1.25%) of samples. The minimum viral load of HCosV was 3.5 × 103 copies/mL from 4 years male patient. The maximum viral load was determined to be 2.4 × 105 copies/mL in one sample obtained from 3.5 years female patient. CONCLUSIONS: This is the first documentation of HCosV detection in cerebrospinal fluid samples that better demonstrates relation of HCosV with neurologic diseases including meningitis and encephalitis. Also, these results indicate that HCosV has been circulating among Iranian pediatric patients.

Genomic surveillance of enterovirus associated with aseptic meningitis cases in southern Spain, 2015-2018.

New circulating Enterovirus (EV) strains often emerge through recombination. Upsurges of recombinant non-polio enteroviruses (NPEVs) associated with neurologic manifestations such as EVA71 or Echovirus 30 (E30) are a growing public health concern in Europe. Only a few complete genomes of EVs circulating in Spain are available in public databases, making it difficult to address the emergence of recombinant EVs, understand their evolutionary relatedness and the possible implication in human disease. We have used metagenomic (untargeted) NGS to generate full-length EV genomes from CSF samples of EV-positive aseptic meningitis cases in Southern Spain between 2015 and 2018. Our analyses reveal the co-circulation of multiple Enterovirus B (EV-B) types (E6, E11, E13 and E30), including a novel E13 recombinant form. We observed a genetic turnover where emergent lineages (C1 for E6 and I [tentatively proposed in this study] for E30) replaced previous lineages circulating in Spain, some concomitant with outbreaks in other parts of Europe. Metagenomic sequencing provides an effective approach for the analysis of EV genomes directly from PCR-positive CSF samples. The detection of a novel, disease-associated, recombinant form emphasizes the importance of genomic surveillance to monitor spread and evolution of EVs.

Clinical characterization of benign enterovirus infection in neonates.

ABSTRACT: Enteroviruses is a group of positive single-stranded RNA viruses ubiquitous in the environment, which is a causative agent of epidemic diseases in children and infants. But data on neonates are still limited. The present study aimed to describe the clinical characteristics of enterovirus infection in neonates and arise the awareness of this disease to general public.Between March 2018 and September 2019, data from all of the neonates diagnosed with enterovirus infection were collected and analyzed from neonatal intensive care unit of Zhangzhou Hospital in Fujian, China.A total of 23 neonates were enrolled. All of them presented with fever (100%), and some with rashes (39.1%). The incidence of aseptic meningitis was high (91.3%), but only a small proportion (28.6%) presented with cerebrospinal fluid (CSF) leukocytosis. The positive value for nucleic acid detection in CSF was significantly higher than throat swab (91.3% vs 43.5%, P = .007). Five of the infected neonates presented with aseptic meningitis (23.8%) underwent brain magnetic resonance imaging examination and no craniocerebral injuries were found. Subsequent follow-ups were performed in 15 of them (71.4%) and no neurological sequelae was found.Aseptic meningitis is a common type of enterovirus infection in neonates with a benign course. Nucleic acid detection of CSF has an important diagnostic value. Febrile neonates would be suggested to screen for enterovirus infection in addition to complete septic workup. An unnecessary initiation or earlier cessation of antibiotics could be considered in enterovirus infection, but that indications still need further studies to guarantee the safety.

Analysis of enterovirus genotypes in the cerebrospinal fluid of children associated with aseptic meningitis in Liaocheng, China, from 2018 to 2019.

BACKGROUND: Aseptic meningitis is most often caused by enteroviruses (EVs), but EVs associated with aseptic meningitis have not yet been reported in Liaocheng. The aim of this study was to determine the prevalence and genetic characteristics of EVs causing aseptic meningitis in children in Liaocheng. METHODS: We reviewed the epidemiological and clinical characteristics of 504 paediatric cases of aseptic meningitis in Liaocheng from 2018 to 2019 and analysed the phylogeny of the predominant EV types causing this disease. RESULTS: A total of 107 children were positive for EV in cerebrospinal fluid samples by nested PCR. Most of the positive patients were children 13 years old or younger and had symptoms such as fever, headache and vomiting (P < 0.05). The seasons with the highest prevalence of EV-positive cases were summer and autumn. The 107 EV sequences belonged to 8 serotypes, and echovirus types 18, 6 and 11 were the three dominant serotypes in Liaocheng during the 2-year study period. Phylogenetic analyses demonstrated that the E18 and E6 isolates belonged to subgenotype C2, while the E11 isolates belonged to subgenotype D5. VP1 analysis suggested that only one lineage of these three types was cocirculating in the Liaocheng region. CONCLUSIONS: This study demonstrated the diverse EV genotypes contributing to a large outbreak of aseptic meningitis in Liaocheng. Therefore, large-scale surveillance is required to assess the epidemiology of EVs associated with aseptic meningitis and is important for the diagnosis and treatment of aseptic meningitis in Liaocheng.

Molecular epidemiology of enteroviruses and predominance of echovirus 30 in an Iranian population with aseptic meningitis.

Human enteroviruses are the most prevalent causes of aseptic meningitis worldwide. However, despite such predominancy, defining the enteroviral etiology of aseptic meningitis remains a diagnostic dilemma for the clinician in Iran. Therefore, this study was conducted to characterize the prevalence and clinical significance of enteroviral aseptic meningitis as well as the predominant enterovirus serotypes among patients with aseptic meningitis in the South of Iran.Cerebrospinal fluid (CSF) specimens were obtained from 73 patients with aseptic meningitis (52.1% males and 47.9% females), ages ranging from 1 month to 88 years. Following the extraction of nucleic acid, the detection of enteroviruses was performed by RT-PCR, targeting the 5' untranslated region of the genome, and sequencing. Enteroviruses were found in 46.6% of samples (34/73). The most predominant serotype was echovirus 30, followed by coxsackievirus B5 and poliovirus type 1 Sabin strain. The enterovirus infections were more prevalent among female patients (58.8%) and those below 5 years of age (52.9%). Although enterovirus infections were observed throughout the year, the infections were more prevalent during autumn with fever as the predominant clinical symptom. The outcomes revealed that enteroviruses are significant causes of aseptic meningitis in the South of Iran, while suspected cases of aseptic meningitis are usually monitored by bacterial culture and biochemical testing of CSF samples. Therefore, the etiology remains unknown in most cases. Molecular detection of viral pathogens should be included as a common approach in the screening of patients with aseptic meningitis to prevent unnecessary treatment and to improve clinical management.

Clinical and laboratory detection of nonpolio enteroviruses among different age groups of aseptic meningitis patients in Alexandria, Egypt.

BACKGROUND: Viral meningitis is the most common type of meningitis. Worldwide, nonpolio enteroviruses (NPEVs) account for 23%-60% of all cases of viral meningitis. We aimed to detect NPEV among aseptic meningitis cases using reverse transcription-polymerase chain reaction (RT-PCR) and evaluate molecular testing versus clinical and laboratory parameters. PATIENTS AND METHODS: A 2-year prospective study was conducted for all clinically suspected meningitis patients, who underwent lumbar puncture in Alshatby University and Alexandria Fever Hospitals. Clinical manifestations were reviewed; cytological, microbiological, and biochemical examinations were done. One-step RT-PCR for NPEV was introduced to a routine workflow using Pan-Enterovirus primers. RESULTS: Out of 2519 patients, 994 (40%) patients were found to have positive cerebrospinal fluid findings, out of which 716 (72%) patients had positive findings of aseptic meningitis. Ninety-four samples were randomly selected and divided across four age groups: neonates, infants, children, and adults. The significant difference was found among adult patients regarding fever, vomiting, headache, signs of meningeal irritation, cranial nerve affection, and focal neurological deficits (p ≤ .05). Seven cases (7.4%) were found to be NPEV positive by RT-PCR. Positive NPEV PCR samples were shown to be statistically significant among neonates (p ≤ .05). The statistical significance was found among the NPEV group regarding the length of hospital stay and duration of IV antibiotic intake while no statistical significance was found with any clinical or laboratory findings. CONCLUSION: RT-PCR was reliable to identify NPEV while clinical and laboratory findings were inconclusive. NPEV showed low incidence and slight seasonal variation which rings the bell to investigate other causes of viral meningitis throughout the year.

Clinical characteristics of echovirus 11 and coxsackievirus B5 infections in Taiwanese children requiring hospitalization.

BACKGROUND: Severe illness can occur in young children infected with certain types of enteroviruses including echovirus 11 (Echo11) and coxsackievirus B5 (CoxB5). The manifestations and outcomes of Echo11 and CoxB5 diseases across all ages of children remained not comprehensively characterized in Taiwan. METHODS: Culture-confirmed Echo11 (60 patients) or CoxB5 (65 patients) infections were identified in a hospital from 2010 to 2018. The demographics, clinical presentations, laboratory data and outcomes were abstracted and compared between the two viruses infections. RESULTS: Echo11 and CoxB5 was respectively identified in 7 (77.8%) and 2 (22.2%) of 9 calendar years. The median age of all patients was 15 months (range, 1 day-14.5 years). For infants ≤3 months old, Echo11 (23 cases) was associated with higher incidence of aseptic meningitis (35% versus 0%, P = 0.003), and a lower rate of upper respiratory tract infections (URI) (22% versus 65%, P = 0.004) compared to CoxB5 (20 cases) infections. For patients >3 months old, URI was the cardinal diagnosis (60%) for both viruses. Aseptic meningitis was also more commonly identified in elder children with Echo11 infections (27% versus 11%), though with marginal significance (P = 0.07). Acute liver failure was identified in four young infants with Echo11 infections including one neonate dying of severe sepsis and myocarditis. All patients with CoxB5 infections recovered uneventfully. CONCLUSION: Aseptic meningitis, sepsis-like illness and acute liver failure were more commonly identified in children with Echo11 than those with CoxB5 infections, suggesting greater neurological tropism and virulence toward Echo11.

Serotype specific epitopes identified by neutralizing antibodies underpin immunogenic differences in Enterovirus B.

Echovirus 30 (E30), a serotype of Enterovirus B (EV-B), recently emerged as a major causative agent of aseptic meningitis worldwide. E30 is particularly devastating in the neonatal population and currently no vaccine or antiviral therapy is available. Here we characterize two highly potent E30-specific monoclonal antibodies, 6C5 and 4B10, which efficiently block binding of the virus to its attachment receptor CD55 and uncoating receptor FcRn. Combinations of 6C5 and 4B10 augment the sum of their individual anti-viral activities. High-resolution structures of E30-6C5-Fab and E30-4B10-Fab define the location and nature of epitopes targeted by the antibodies. 6C5 and 4B10 engage the capsid loci at the north rim of the canyon and in-canyon, respectively. Notably, these regions exhibit antigenic variability across EV-Bs, highlighting challenges in development of broad-spectrum antibodies. Our structures of these neutralizing antibodies of E30 are instructive for development of vaccines and therapeutics against EV-B infections.

Evaluation for Arboviral Infection Among Children Hospitalized in Colorado With Aseptic Meningitis and Encephalitis.

Among 39 children hospitalized in Colorado with aseptic meningitis or encephalitis, 16 (41%) had an etiology identified, including 2 (5%) with West Nile virus infection. Despite extensive testing, no other arboviral infections were identified. Arboviral infection should be considered in children with neuroinvasive disease during arboviral season with testing directed toward viruses endemic to the region and type of exposure.

Impact of rapid enterovirus polymerase chain reaction testing on management of febrile young infants < 90 days of age with aseptic meningitis.

BACKGROUND: Diagnostic evaluation of febrile young infants is challenging. Empirical antimicrobial treatment is therefore common practice in this setting despite high percentage of causative viral infections. The objective of this study was to investigate the impact of rapid enterovirus cerebrospinal fluid polymerase chain reaction (CSF EV PCR) test on hospital length of stay (LOS) and antimicrobial treatment duration in young febrile infants. METHODS: Retrospective observational study comparing duration of antimicrobial treatment and hospital LOS before (May 1, 2014 - May 30, 2015, untested group) and after (June 1, 2015 - June 30, 2017, tested group) the introduction of rapid CSF EV PCR testing in infants < 90 days of age presenting with fever and CSF pleocytosis at the University Children's Hospital Zurich. Additionally, the same variables were compared after test introduction between CSF EV PCR positive and negative children. RESULTS: One hundred twenty-eight children were enrolled in the study, 58 before and 70 after the introduction of rapid CSF EV PCR testing. Duration of antimicrobial treatment was significantly shortened in EV positive (n = 42) compared to both EV negative (n = 28) (median 18 h and 48 h, respectively, p < 0.001) and untested patients (n = 58) (median 18 h and 48 h, respectively, p < 0.001), and also in tested compared to untested group patients (median 36 vs 48 h, p < 0.001). Hospital LOS was significantly shortened in EV positive compared to EV negative patients (median 3 days and 4 days respectively, p = 0.013), while an overall reduction was not observed between tested and untested group patients. CONCLUSIONS: In this study we demonstrate that antimicrobial treatment duration could be significantly shortened in neonates and young infants < 90 days of age with aseptic meningitis after the introduction of a rapid CSF EV PCR test compared to untested patients before test introduction.

Genetic characterization of a novel recombinant echovirus 30 strain causing a regional epidemic of aseptic meningitis in Hokkaido, Japan, 2017.

A regional epidemic of aseptic meningitis caused by echovirus 30 (E30) occurred in Hokkaido, Japan, during the period of August-December 2017. To investigate their phylogenetic relationship to other human enteroviruses, we determined the complete genomic nucleotide sequences of isolates from this outbreak. Phylogenetic analysis of the viral capsid protein 1 gene showed that the strains were most closely related to E30 strains detected in Germany, France, and Russia in 2013. In contrast, the region encoding the viral protease and the RNA-dependent RNA polymerase had a close phylogenetic relationship to non-E30 enteroviruses detected in the United Kingdom and Switzerland in 2015-2017, suggesting that a recombination event had occurred.

Increased detection of enterovirus A71 infections, Germany, 2019.

We report on the increased circulation of enterovirus A71 in Germany in 2019. Strains were mainly identified in hospitalised patients with suspected aseptic meningitis/encephalitis. Molecular analysis showed co-circulation of EV-A71 sub-genogroups C1 and C4, a signal for physicians and public health authorities to include/intensify EV diagnostic in patients showing signs of aseptic meningitis, encephalitis or acute flaccid paralysis/myelitis.

Aseptic meningitis caused by torque teno virus in an infant: a case report.

BACKGROUND: Torque teno virus-induced aseptic meningitis has not been documented, although torque teno virus infections still remain under consideration for etiological agents. This study identified a torque teno virus sequence using next generation sequencing and immunoglobulin M response to the torque teno virus antigen, therefore, that would be a comprehensive diagnosis for torque teno virus infection. CASE PRESENTATION: A 2-month-old Japanese boy was brought to our hospital because he was irritable, drowsy, and lethargic. He was admitted based on his test results which indicated the possibility of septic meningitis. He was started on treatment with high-dose antibiotics and steroids. On the third day of hospitalization, he became afebrile with improvement in his general status and was discharged on the sixth day. He had no developmental problems for up to 1 year after discharge. Metagenomic ribonucleic acid-Seq pathogen detection using next generation sequencing of a sample of his cerebrospinal fluid, which was collected at admission, revealed three short reads homologous to those in torque teno virus out of a total of 1,708,516 reads. This finding indicated that our patient was positive compared to the torque teno virus-negative cerebrospinal fluid samples (controls) from 13 other patients. The torque teno virus has been shown to have a whole genome sequence of 2810 nt by polymerase chain reaction. We prepared a recombinant GP2 antigen from torque teno virus and used it to study our patient's anti-torque teno virus immune response. An anti-GP2 serum immunoglobulin M response was detected, providing further supportive evidence of torque teno virus infection. CONCLUSIONS: This case speculates that torque teno virus-induced aseptic meningitis has a good course. New technologies like next generation sequencing can help in the identification of such cases, and an accumulation of future cases is expected.

Identification and Phylogenetic Characterization of Human Enteroviruses Isolated from Cases of Aseptic Meningitis in Brazil, 2013-2017.

Aseptic meningitis is a common viral infection associated with human enteroviruses. The aim of the present study was to identify and characterize the enteroviruses associated with outbreaks and sporadic cases of aseptic meningitis that occurred in different regions of Brazil between 2013 and 2017. Cerebrospinal fluids obtained from patients admitted to public health facilities were analyzed. A total of 303 patients were positive for Human Enteroviruses (EV) by cell culture isolation with a median isolation rate throughout the year of 12%. We were able to identify enterovirus serotypes in 295 clinical specimens. Nineteen different serotypes were identified; the large majority corresponded to HEV-B species. Echovirus 30 (E-30) and Echovirus 6 (E-6) were the most prevalent genotypes (66.8%). Sequence analysis suggested that circulating E-30 was closely related to E-30 from other American countries; while E-6 was derived from Europe. Most of the patients consisted of children ≤ 15 years old. The temporal distribution of all aseptic meningitis and EV-positive cases showed an obvious seasonal pattern during autumn. Our results have provided valuable information about the enteroviral etiology of the aseptic meningitis cases in Brazil pointing to the importance of enterovirus surveillance in neurological diseases.

High proportion of coxsackievirus B3 genotype A in hand, foot and mouth disease in Zhenjiang, China, 2011-2016.

BACKGROUND: Hand, foot and mouth disease (HFMD) is usually caused by EVA71 and CVA16 except for a few cases that are caused by non-EVA71 non-CAV16 enteroviruses. Coxsackievirus B3 (CVB3) is mostly associated with myocarditis, occasionally with HFMD. METHODS: The partial VP1 gene of enteroviruses were amplified and sequenced from 610 throat swabs from clinically confirmed HFMD children. All available CVB3 near full-length genomic and VP1 sequences were downloaded from GenBank. Phylogenetic and distance analyses were performed using MEGA 7.0. RESULTS: A total of 238 partial VP1 sequences were obtained, including 93 EVA71 (39%), 79 CAV16 (33%), 29 CVB3 (12%), 24 CVA6 (10%), and 13 other enterovirus serotypes (5.5%). CVB3 is classified into seven genotypes A-G according to phylogenetic and distance analyses. All CVB3 strains from Zhenjiang belonged to genotype A. In contrast to other genotypes that are prevalent in Europe and other regions of China, and often associated with aseptic meningitis and myocarditis, CVB3 genotype A strains identified in Zhenjiang were only detected among HFMD patients. CONCLUSIONS: This high prevalence of CVB3 genotype A among HFMD children has never been reported. This phenomenon has revealed a new epidemic trend of CVB3 among HFMD in China, and it has epidemiological implications for monitoring the epidemic risk of CVB3.

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.