Enterovirus Research Articles

Beyond Poliomyelitis: A 21-Year Study of Non-Polio Enterovirus Genotyping and Its Relevance in Acute Flaccid Paralysis in São Paulo, Brazil

In the context of the near-global eradication of wild poliovirus, the significance of non-polio enteroviruses (NPEVs) in causing acute flaccid paralysis (AFP) and their impact on public health has gained increased attention. This research, conducted from 2001 to 2021, examined stool samples from 1597 children under 15 years in São Paulo, Brazil, through the AFP/Poliomyelitis Surveillance Program, detecting NPEVs in 6.9% of cases. Among the 100 NPEV-positive strains analyzed, 90 were genotyped through genomic sequencing of the partial VP1 region, revealing a predominance of EV-B species (58.9%), followed by EV-A (27.8%) and EV-C (13.3%). This study identified 31 unique NPEV types, including EV-A71, CVB2, and E11, as the most prevalent, along with the first documented occurrence of CVA19 in Brazil. These findings emphasize the importance of NPEV genotyping in distinguishing AFP from poliomyelitis, enhancing understanding of these viruses’ epidemiology. Moreover, it ensures that AFP cases are correctly classified, contributing to the effective surveillance and eradication efforts for poliomyelitis.

Impact of Sample Storage Time and Temperature on the Stability of Respiratory Viruses and Enteric Viruses in Wastewater

Wastewater-based surveillance (WBS) has been widely used to track SARS-CoV-2 as well as many other viruses in communities during the COVID pandemic and post-pandemic. However, it is still not clear how temperature and storage time would influence the stability of viruses in wastewater. In this study, we assessed the stability of SARS-CoV-2, pepper mild mottle virus (PMMoV), influenza viruses A (IAV) and B (IBV), respiratory syncytial virus (RSV), and enteric viruses in raw wastewater stored at room temperature, 4 °C, and −20 °C for 3 and 6 days. SARS-CoV-2, PMMoV, IAV, and enteric viruses were found to be stable up to 6 days after storing at room temperature or 4 °C. SARS-CoV-2 and RSV were more susceptible to freeze–thaw cycles compared to PMMoV and enteric viruses, which were relatively stable for up to 6 days stored at −20 °C. Low detection of IBV in wastewater made it difficult to evaluate the impact. Based on our findings, we conclude that short-term storage or transportation of wastewater samples within 6 days at ambient temperature or 4 °C is acceptable for the majority of these viruses. Freezing samples at −20 °C for even short periods is not recommended for WBS of respiratory viruses. The data obtained from this study can provide guidance for quality assurance purposes from the operational aspects of wastewater surveillance.

Childhood acute flaccid myelitis, including the first confirmed cases of enterovirus D68 myelitis, in Singapore and Southeast Asia.

We report the epidemiology, treatment and outcomes of acute flaccid myelitis (AFM), including the first two cases of enterovirus (EV) D68 myelitis, in Singapore. Retrospective observational study from a paediatric hospital in Singapore, from January 2012 to December 2022. Clinical, laboratory, neuroimaging and outcome data were analysed. Eight patients were identified (all male). Median age at presentation was 3 (interquartile range (IQR) 2.2-10.0) years. Seven (87.5%) patients were clustered in two time periods (July 2018-January 2019 and April-August 2022). Presenting features were a preceding febrile respiratory illness (n = 6) or hand-foot-and-mouth disease (n = 2), upper limb weakness (n = 5, 62.5%) and neurogenic bladder (3, 37.5%), while the spinal cord lesions were predominantly in the cervical region (7, 87.5%). Five (62.5%) and six (75.0%) patients had elevated cerebrospinal fluid (CSF) white cells (median 7.5/mm3 (IQR 2.8-40.3)) and protein (median 0.6 g/L (IQR 0.4-0.7)), respectively. CSF was negative for pathogens. Two (50%) of four patients with EV detected in respiratory/rectal swabs had EVD68 (2022 cluster). All received intravenous methylprednisolone, six (75%) had additional intravenous immunoglobulin and either plasma exchange therapy (n = 1) or intravenous tocilizumab (n = 1). Median modified Rankin Scale (mRS) at acute illness was 4 (IQR grades 3-5), with an improvement (median 2 (IQR 1.8-2.3) mRS grades) on follow-up (median duration 3.7 (IQR 1.4-4.1) years). One patient (12.5%) had a full recovery and seven (87.5%) have moderate disability (mRS 2-3). Disability risk in AFM is high despite aggressive immunotherapy. We report the first two confirmed cases of EV D68 AFM in Singapore and Southeast Asia.

Etiological, Clinical, and Epidemiological Characteristics of Acute Viral Gastroenteritis in an Adult Population in a Tertiary Level Hospital in Spain.

Acute gastroenteritis (AGE) represents a significant global health burden, with enteric viruses being a leading cause of gastroenteritis worldwide. Despite advances in diagnosis and treatment, there are limited data on adults seeking care due to AGE of viral etiology. This study aimed to describe the etiological, clinical, and epidemiological characteristics of viral AGE in adult patients presenting for medical consultation in a tertiary hospital over a 2-year period. A retrospective cross-sectional study was conducted, with 8886 stool samples from 8356 adult patients presenting acute diarrhea between January 2021 and December 2022. A molecular real-time RT-PCR panel was used to screen for common bacterial, parasitic, and viral pathogens. Clinical and demographic data were collected, and statistical analysis was performed to evaluate possible associations. Enteric viruses constituted 10.3% (307 cases) of all AGE of known etiology, with norovirus being the predominant pathogen (196, 63.8%), followed by rotavirus (82, 26.7%) and adenovirus (29, 9.4%). The different viruses showed a distinct seasonal predominance. Coinfection with other microorganisms was common. Most cases exhibited a self-limiting course. Mortality and hospitalization rates were high in patients with higher comorbidity indices, mainly in individuals with immunosuppression. Viruses are an important cause of acute gastroenteritis in adults presenting for medical consultation. The new multiplex molecular tests with high sensitivity and specificity allow early differential diagnosis in AGE. It is therefore necessary to identify which special populations particularly with higher comorbidity indices, would benefit from the implementation of these techniques, to guide decision-making related to appropriate treatments and avoid unnecessary interventions.

Impact of Wastewater Use for Irrigation and Contamination of Lettuce by Enteric Viruses: Case of Ouagadougou Market Gardening Sites, Burkina Faso.

Raw vegetables irrigated with polluted water that may contain enteric viruses can be associated with foodborne viral disease outbreaks. The objective of this study is to investigate the possible transmission of enteric viruses from irrigation water to lettuce. Therefore, we performed a commercial multiplex real-time PCR assay to monitor the occurrence of enteric viruses in irrigation water samples and in raw vegetables that were cultivated at market gardening sites in Ouagadougou, Burkina Faso. Samples were collected from six market gardening sites located in Ouagadougou. RT-PCR was performed to detect norovirus GI, norovirus GII, rotavirus, enteric adenoviruses F (Serotype 40/41), astrovirus and sapovirus (Genogroups G1, 2, 4, 5). From the 10 irrigation water samples and the 80 lettuce samples, three (30%) and twenty-two (27.5%) were positive for enteric viruses, respectively. Norovirus GII, astrovirus and enteric adenoviruses F (Serotype 40/41) were the most frequently detected viruses in lettuce and irrigation water samples. Our results indicate that raw vegetables may be contaminated with a broad range of enteric viruses, which may originate from virus-contaminated irrigation water, and these vegetables may act as a potential vector of food-borne viral transmission.

Detection of human enteric viral genes in a non-native winter crane fly, Trichocera maculipennis (Diptera) in the sewage treatment facilities at Antarctic stations

BackgroundThe Antarctic environment is susceptible to the introduction of non-native species due to its unique ecosystem, which has evolved under geographical isolation and extreme climatic conditions over an extended period. The recent introduction of the non-native winter crane fly, Trichocera maculipennis, to maritime Antarctica may pose a potential threat to the Antarctic ecosystem. In this study, we evaluated the possibility of the mechanical transmission of viruses by T. maculipennis.MethodsWe assessed the potential for the mechanical transmission of viruses using next-generation sequencing (NGS), quantitative PCR (qPCR), and virus isolation methods from T. maculipennis (Tm)-related samples (Tm body-wash fluid and Tm body-ground samples) collected from habitats and sewage treatment facilities located at three research stations in Antarctica.ResultsVirome analysis detected the genomic fragments of human adenovirus (AdV) and human endogenous retrovirus (HERV) in Tm-related samples. These viruses are commonly found in human feces. In addition, plant viruses, such as pepper mild mottle virus (PMMoV) and cucumber green mottle mosaic virus (CGMMV), both known indicators of enteric viruses, were identified in all Tm-related samples, likely originating from wastewater. However, the low quantities of AdV and HERV genomes detected in Tm-related samples through qPCR, coupled with the non-viability of AdV in virus isolation tests, indicate that T. maculipennis has limited potential for mechanical transmission under the conditions in the studies.ConclusionsOur study represents the first evaluation of the potential risk of non-native species serving as vectors for viral pathogens in Antarctica. Although the viruses detected were in relatively low quantities and non-viable, this study highlights the importance of further evaluating the risks associated with non-native species, particularly as the likelihood of their introduction increases to Antarctica due to climate change and increased human activity.Graphical abstract

Detection and Molecular Characterization of Avian Encephalomyelitis Virus in India: A Preliminary Report

Tremovirus A, previously recognized as Avian encephalomyelitis virus (AEV) is, one of the viruses that have been reported to be associated with nervous and enteric disorders in young birds. In Kerala, there has been an increase in the cases of nervous and enteric diseases in chickens. The detection and characterization of other viruses associated with nervous and enteric viruses in chickens has been established in Kerala. While there have been reports of nervous and enteric diseases in chickens in the region, no previous research had focused on AEV as the causative agent. A total of 50 samples were tested to detect AEV by reverse-transcriptase polymerase chain reaction (RT-PCR) targeting the 5' untranslated region (5'UTR) of AEV. Of the samples tested, one (2%) was found to be positive for the virus. The most immunogenic protein of AEV is VP1 protein forming the major capsid protein. The VP1gene segment of the detected virus isolate was amplified and molecular characterization was done. The phylogenetic analysis of the VP1 gene sequence revealed that the virus was identical to AEV viruses detected in Hungary, China, and Hong Kong (64% similarity). The current isolate showed a nonsynonymous mutation of I184V which was noticed only in Hungary isolate. The results of the study indicate that AEV is rarely present in chickens of Kerala, India, and that its occurrence is very low. Since the virus is capable of inducing nervous signs, mortality, and economic losses, measures are to be taken to control the spread of the virus in chickens in Kerala, India.

Characterization of oral microbiota of children with hand, foot, and mouth disease caused by enterovirus A 71

BackgroundThe association between alterations in the oral microbiome and hand, foot, and mouth disease (HFMD) has been observed in previous studies. Our study, therefore, aimed to identify the structural changes in the oral microbiota and biomarkers in children with HFMD caused by enterovirus A 71 (EV-A71).MethodsChildren diagnosed with EV-A71 HFMD and healthy children recruited from April 2021 to September 2023 were included in the present study, and were categorized into EV-A71 and control groups, respectively. Oral swabs were collected and microbiota information was obtained using 16 S rRNA gene sequencing technology. Alpha-diversity and partial least squares discriminant analyses were conducted to compare microbial diversity, richness, and similarity between the two groups. Linear discriminant analysis effect size was employed to identify microbial taxa with significant differences, and determined the key genera among them.ResultsThe study included a total of 80 children, with 50 assigned to the EV-A71 group and 30 to the control group. No significant differences were found between the two groups in terms of age (2.2 ± 1.2 vs. 2.7 ± 1.2 years; age range: 1–5 years; P = 0.114) or sex (56% vs. 60% boys, P = 0.726). The oral microbiota structure in the EV-A71 group differed from that in the control group. The EV-A71 group showed significant reductions in both the Shannon index (P = 0.037) and the abundance-based coverage estimator (ACE) index (P < 0.001). The key genus changes were marked by a significant decrease in the abundance of Capnocytophaga (P = 0.002) and Leptotrichia (P = 0.033) in the EV-A71 group.ConclusionIn children with EV-A71 HFMD, the oral microbiota showed changes in composition, with a significant reduction in diversity and richness. The changes in key genera were a marked decrease in the abundance of Capnocytophaga and Leptotrichia.

Genetic Characteristics and Phylogenetic Analysis of Coxsackievirus A6 Isolated in Linyi, China, 2022-2023.

Hand, foot, and mouth disease (HFMD) has become one of the most common infectious diseases in the past few decades. Since 2013, coxsackievirus A6 (CVA6) has replaced enterovirus A71 (EV-A71) and coxsackievirus A16 (CVA16), becoming the predominant pathogen responsible for HFMD in many areas of China. This study aimed to investigate the genetic characteristics and molecular epidemiology of CVA6 in Linyi between the years 2022 and 2023. In total, 965 patients with HFMD were enrolled in this study, and analyses based on VP1 nucleotide sequences were performed to determine the evolutionary trajectory of CVA6. In 2022, 281/386 (72.8%) patients were positive for enteroviruses (EVs) and 217/281 (77.2%) were CVA6 positive. In 2023, 398/579 (68.7%) samples were positive for EVs and 243/398 (61.1%) were CVA6 positive. Six sequences were selected each year for homology analysis. The results showed that the 12 strains isolated from Linyi were distant from the prototype strain (AY421764) and the first CVA6 strain reported in China (JQ364886). Phylogenetic analysis showed that the CVA6 strains isolated from Linyi belonged to the D3 sub-genotype. CVA6 is emerging as a common pathogen causing HFMD in Linyi and continuous surveillance of HFMD etiologies agents is necessary.

A RNA-seq-based study on differentially expressed genes related to the Inner Mongolia EV71 C33λ strain that invades Vero cells

Enterovirus 71 (EV71) is a significant causative agent of hand, foot and mouth disease (HFMD). However, the precise mechanism by which EV71 infection leads to alterations in the immune response remain elusive. To address this knowledge gap, we conducted a study where we introduced the Inner Mongolia EV71 C33λ strain into Vero cells, derived from African green monkey kidney cells. Subsequently, we performed RNA sequencing (RNA-Seq) to investigate the changes in the transcriptome of these infected Vero cells. Our primary objective was to establish a foundational understanding that could inform future research on EV71-associated immune factors. In our study, we identified a total of 942 differentially expressed genes (DEGs) in Vero cells infected with Enterovirus 71 (EV71), with 568 gene exhibiting increased expression and 374 gene showing decreased expression. To elucidate the functional implications of these DEGs, we conducted a comprehensive functional enrichment analysis using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. This analysis revealed three genes that were significantly upregulated, which we subsequently validated using reverse transcription polymerase chain reaction technology (RT-qPCR). The RT-qPCR results were in strong agreement with our RNA-Seq data, confirming the reliability of our findings. This study represents the pioneering RNA-Seq analysis that delves into the cellular response of Vero cells to EV71 infection. Our results not only provide a foundational understanding of the molecular changes induced by EV71 but also offer crucial insights into the mechanisms by which EV71 modulates the host immune system. These insights are pivotal for future research endeavors aimed at developing effective therapeutic strategies against EV71 and related pathogens, as well as for understanding the broader implications of viral infections on host immunity.

Etoposide targets 2A protease to inhibit enterovirus 71 replication

ABSTRACT Enterovirus 71 (EV71) is a major pathogen that causes hand, foot, and mouth disease (HFMD) in infants and children. Notably, no clinically approved drugs specifically target EV71. The EV71 2A protease (2A pro ), a cysteine protease produced by the virus, is essential for the virus’ replication and has a significant impact on the functioning of host cells. Thus, it presents a valuable target for the discovery of antiviral medications. In this study, based on the monomers and their derivatives in the Library of Traditional Chinese Medicine (TCM), we performed virtual screening and biological experiments. We identified a derivative of a traditional herbal monomer, Etoposide, commonly isolated from the roots and rhizomes of Podophyllum spp. Etoposide inhibited replication of EV71 A, B, C, and CVA16 viruses in a concentration-dependent manner in a variety of cell lines with minimal cytotoxicity. Furthermore, both molecular dynamics simulations and site-directed mutagenesis assays revealed that Etoposide inhibited the activity of the EV71 2A protease by mainly binding to two residues, Y89 and P107. The findings indicate that Etoposide serves as a promising inhibitor of the EV71 2A pro , demonstrating strong antiviral properties and positioning itself as a formidable candidate for clinical trials against EV71. IMPORTANCE We first used a drug screening approach focused on monomeric compounds and their derivatives from traditional Chinese medicine to identify an EV71 2A pro inhibitor—Etoposide. We then performed biological experiments to validate that Etoposide suppresses the replication of the EV71 virus in a concentration-dependent manner with minimal cytotoxicity to various cell lines. Remarkably, it shows inhibitory activity against EV71 A, B, C, and CVA16, suggesting that Etoposide may be a potential broad-spectrum inhibitor. We revealed a novel mechanism that Etoposide inhibits EV71 proliferation by targeting 2A pro , and the interactions with Y89 and P107 are of great importance. The findings suggest that Etoposide serves as a promising inhibitor of EV71 2A pro , demonstrating significant antiviral properties. It stands out as a strong candidate for broad-spectrum applications in clinical research.

Incidence, clinical manifestations and characterization of Enterovirus in the last decade (2014-2023) in Asturias (Spain). Effect of the SARS-CoV-2 pandemic.

Enteroviruses (EVs) are a large group of genotypes that cause a variety of pathologies, some of them very serious. This study analyzed the last 10 years (2014-2023) of EVs diagnosis and classification. In 166,674 samples collected, EVs were found in 9,535 (5.7%) by rt-RT-PCR, and 332 (3.5%) were classified by Sanger methods. Symptoms were analyzed in 7623 cases. EVs were found in 5718/63,829 (8.9%) before, 1384/42,373 (3.3%) during and 2433/60,472 (4%) after the Covid pandemic (p < 0.0001), and in 7249/69,700 (10.4%) children under 6 years and in 2286/96,974 (2.35%) in oldest (p < 0.0001). The positive rate of EVs was high but decreased during the Covid period. In the youngest children EVs-A (associated with exantematohous disorders as well as respiratory manifestations and febrile syndromes) was most common, while EVs-B (frequent in neurological symptoms) was most common in children aged 6-15 years and EVs-D (associated to respiratory manifestations) in adults.

Molecular epidemiology of herpangina in the subcenter of Beijing, China: a surveillance study during 2021-2022.

In this study, we analyzed the dynamic molecular epidemiology of herpangina based on pharyngeal swabs and demographic data collected from children with herpangina monitored in Tongzhou district in China from January 2021 to December 2022. A total of 1022 herpangina cases were diagnosed. Out of 225 samples collected, 56.4% (127/225) were positive for non-polio enterovirus, with seven genotypes identified: coxsackievirus A4 (CV-A4), CV-A6, CV-A10, CV-A2, CV-A16, CV-B3, and CV-A8. The predominant genotypes associated with herpangina changed during and after the COVID-19 pandemic, with the predominant genotypes being CV-A4 and CV-A6 in 2021 and CV-A10 and CV-A6 in 2022.

Application of Pan-Viral Metagenomic Sequencing on United States Air Force Academy Wastewater to Uncover Potential Causes of Acute Gastroenteritis.

Wastewater surveillance is an important technique to monitor public health and is being studied extensively for pandemic prevention, force health protection and readiness, and as a potential early warning system for chem-bio defense. Wastewater surveillance has traditionally relied on techniques such as quantitative PCR or targeted sequencing, both of which are microbe- or disease-specific tools. Newer pan-viral metagenomics strategies may provide higher specificity for pathogens of interest, resulting in a lower false negative rate and reduced sequencing of undesired background nucleic acids. One such system, VirCapSeq-VERT, has been developed to targetall vertebrate virus pathogens; until recently, its application has been limited to clinical samples. The objective of this study was to use VirCapSeq-VERT to interrogate wastewater samples from the U.S. Air Force Academy (USAFA), Colorado Springs, Colorado, to determine its utility in assessing complex samples and its potential application in public health surveillance. Biweekly samples were analyzed from February 2022 through May 2023. Samples were collected from the wastewater treatment facility at USAFA before treatment and stored at -20 °C until total nucleic acid (tNA: DNA and RNA) extraction. tNA was then subject to the probe-based capture system, VirCapSeq, and run through a collection of public bioinformatics pipelines to identify captured viral pathogens and perform phylogenetic analysis. It was determined by the USAFA IRB that the study was non-human subject research and was deemed exempt. In total, 68 families of viruses were identified, comprising thousands of individual strains. This study focused on viruses responsible for gastrointestinal dysfunction as a test of the use of the VirCapSeq-VERT to identify human pathogenic viruses within a complex and highly enriched biological sample. Four enteric viruses dominated the wastewater samples, with Adenoviridae most prevalent before the cadet winter recess (December 17, 2022-January 4, 2023) and Astroviridae most abundant thereafter. Although gastroenteritis outbreaks at USAFA are commonly attributed to norovirus because of clinical presentation and the acute nature of the illness-often diagnosed and treated without confirmatory stool testing-this virus was not found in high prevalence in these wastewater samples. Among adenoviruses, F serotype 41 predominated, suggesting a role in gastrointestinal infections among the cadet population. Phylogenetic investigation of adenovirus and norovirus exposed common variants with seasonal distributions. These findings may prompt correlational studies to assess the clinical predictive capability of VirCapSeq-VERT and to determine the utility of wastewater monitoring as an outbreak early warning system.

Recent Molecular Epidemiology of Echovirus 11 Throughout North and West Africa Resulted in the First Identification of a Recombinant Strain from an Acute Flaccid Paralysis Case in West Africa.

Echovirus 11 has emerged as a major public health concern, causing sepsis in neonates in many European countries in recent years. In Africa, especially West Africa, where resources and diagnostic capacities are limited, only sporadic cases have been reported. To better understand the recent molecular epidemiology of E11 in West Africa, we characterized twenty-three echovirus 11 strains isolated through the acute flaccid paralysis and environmental surveillance systems for polio from 2013 to 2023, using high-throughput sequencing. Our data are noteworthy due to identifying for the first time a recombinant strain from an acute flaccid paralysis case and represent the first focus to date on molecular characterization of echovirus 11 in West Africa. Moreover, our data show that echovirus 11 diverged from 1970 (95% HPD range, 1961-1979) and evolved into four distinct clades, with the virus spread from West Africa to Europe, exhibiting two introductions in France around 2017, from Senegal and Guinea. Furthermore, the in silico analysis reveals four non-conservative amino acid substitutions in the VP1 sequences of the European strains associated with neonatal sepsis in newborns and a conserved amino acid motif in the VP1 protein toward enterovirus genotypes. Our data provide new insights into the epidemiology of echovirus 11 and point to the crucial need to implement specific surveillance programs targeting non-polio enteroviruses for the rapid identification of emerging or re-emerging enterovirus species, particularly in Africa.

First investigation of Ostreid herpesvirus-1 and human enteric viruses in a major scallop production area in Brazil.

Bivalve mollusks may be affected by numerous infectious diseases, which cause high mortality rates and economic burdens for producers. Another challenge for bivalve aquaculture is the protection of farms from human contamination, such as sewage and stormwater discharges. Ilha Grande Bay (IGB), located in Rio de Janeiro state, is the largest Brazilian producer of scallops (Nodipecten nodosus). This region has recently suffered a mass mortality of mollusks, and several environmental contaminants have been reported in the area. To contribute to the elucidation of scallop collapse and better characterize the human impacts, this study assessed the circulation of mollusk (Ostreid herpesvirus-1 [OsHV-1]) and human (mastadenovirus [HAdV] and norovirus GII) viral pathogens in waters and animals produced at IGB. Neither water nor animals were positive for OsHV-1. However, of the 7 points analyzed, 5 points showed contamination by HAdV or norovirus. HAdV and norovirus were detected in 5.5 and 6.9% of the analyzed water samples, respectively, in concentrations ranging from 2.39 × 103 to 1 × 105 genome copies/L. One scallop sample was positive for norovirus (4.5%). These results demonstrate human contamination in the region, presenting a risk of consumer contamination, and a non-association between OsHV-1 and the mass mortality described in scallops.

Identification of the Emerging C1-like Lineage of Enterovirus A71 in Two Uruguayan Children with Hand-Foot-and-Mouth Disease and Neurological Complications.

Enterovirus A71 (EV-A71) is a major cause of hand-foot-and-mouth disease (HFMD), particularly in cases that involve complications affecting the nervous system or cardiopulmonary function. In South America, EV-A71 has primarily been identified through studies of acute flaccid paralysis (AFP) and other neurological disorders. In September 2022, two children from a small city in Uruguay were hospitalized with presumptive rhombencephalitis, exhibiting symptoms of HFMD. EV-A71 was identified through RT-PCR and next-generation sequencing of stool and skin lesion samples. A maximum-likelihood phylogenetic analysis of the P1 coding region classified the Uruguayan strains as part of an emerging lineage, primarily reported in Europe over the past decade, known as the C1-like lineage. The findings presented here represent the first detection of the EV-A71 C1-like lineage in cases of HFMD and encephalitis reported from South America, underscoring the urgent need to enhance surveillance for HFMD, aseptic meningitis, encephalitis, and AFP, in countries facing challenges in establishing effective surveillance programs related to enteroviruses and associated diseases.

Evaluation of the Intensive Acute Flaccid Paralysis Surveillance System in Ghana: Post the Switch from tOPV to bOPV.

The Global Polio Eradication Initiative was adopted by Ghana in 1996, and through robust AFP surveillance was able to interrupt the circulation of wild poliovirus in 2008. However, the country suffered vaccine-derived poliovirus type 2 outbreaks in 2019 and 2022. We conducted a retrospective analysis of all AFP surveillance data received by the polio program in Ghana from 2018 to 2022. An analysis of the WHO performance indicators for evaluating a surveillance system was conducted using Epi Info 3.5.4 and Microsoft Excel. Of the 4832 cases investigated, 56.3% were males, 71.1% comprised children aged 5 years and below, and more than half (65.2%) had received a maximum of three doses of OPV. Over 77% (3028) had a fever at the onset of paralysis, and 67.8% had paralysis progression within 3 days. The non-polio AFP rate of ≥2 and the stool adequacy rate exceeded the target of ≥80% in nearly every study year. The proportion of non-polio enteroviruses isolated surpassed the target of ≥10% in all years except 2018. The AFP surveillance system in Ghana is sensitive and representative. Though the surveillance became more intensive and proactive during the outbreak, the system needs to focus on improving the completeness of the data as well as the timeliness of the arrival of stool specimens within 3 days of collection.

Stress from environmental change drives clearance of a persistent enteric virus.

Persistent viral infections are associated with long-term health issues and prolonged transmission. How external perturbations after initial exposure affect the duration of infection is unclear. We discovered that murine astrovirus, an enteric RNA virus, persists indefinitely when mice remain unperturbed but is cleared rapidly after cage change. Besides eliminating the external viral reservoir, cage change also induced a transcriptional defense response in the intestinal epithelium. We further identified that displacing infected animals initially caused a temporary period of immune suppression through the stress hormone corticosterone, which was followed by an immune rebound characterized by an increase in CD8 T cells responsible for the epithelial antiviral responses. Our findings show how viral persistence can be disrupted by preventing re-exposure and activating immunity upon stress recovery, indicating that external factors can be manipulated to shorten the duration of a viral infection.

Epidemiology of Acute Infectious Diarrhea-Associated Viruses in Children in Hangzhou, China, 2023

Abstract Objective To investigate the epidemiological characteristics of children infected with diarrheal virus in Hangzhou, China, 2023. Methods From January 2023 to December 2023, 20,939 stool samples from children with acute infectious diarrhea were collected for the detection of rotavirus A and human adenovirus (HAdV), using latex agglutination detection kits; 7,584 stool samples were collected for the detection of norovirus, using real-time polymerase chain reaction reagent. Results A total of 639 (3.0%, 639/20,939) tested positive for rotavirus A, and 1,201 (5.7%, 1,201/20,939) positive samples were detected by colloidal gold method. The positive rates of norovirus were 42.2% (3,203/7,585). Among all age groups, the rotavirus A positive detection rate was the highest in participants aged 3 to 6 years (6.46%, 260/4,024). The monthly distribution of patients with rotavirus A showed that the number of cases was the lowest in October (0.45%, 8/1,779) and reached the peak in April (7.97%, 144/1,806). The highest and lowest positive rates among all age groups for HAdV were found in children aged 3 to 6 years(8.27%, 333/4,024) and in those aged 0 to 6 months (2.21%, 60/2,717). The monthly positivity rates of HAdV spanning from January to November 2023 were 1.38, 1.44, 2.34, 3.65, 6.64, 7.71, 7.54, 7.13, 6.82, 4.15, and 6.50%, and reached the peak in December (8.17%). For norovirus, children aged 1 to 3 years had the highest positive detection rate (57.95%, 1,349/2,328), while infants aged 0 to 6 months had the lowest positive detection rate (19.60%, 205/1,046). The results show that January had the lowest number of cases (14.63%, 6/41), while September had the highest (50.51%, 545/1,079). Conclusion The detection rate of rotavirus A and HAdV was highest among participants aged 3 to 6 years, whereas the detection rate of norovirus was highest among those aged 1 to 3 years. The monthly distribution peaks for the three enteric viruses varied significantly.