Long-term neurodevelopment outcomes of hand, foot and mouth disease inpatients infected with EV-A71 or CV-A16, a retrospective cohort study

Arginine depletion-induced autophagy and metabolic dysregulation are involved in the disease severity of hand, foot, and mouth disease

Amino acid metabolism provides significant insight into the development and prevention of many viral diseases. Therefore, the present study aimed to compare the amino acid profiles of hand, foot, and mouth disease (HFMD) patients with those of healthy individuals and to further reveal the molecular mechanisms of HFMD severity. Using UPLC-MS/MS, we determined the plasma amino acid expression profiles of pediatric patients with HFMD (mild, n = 42; severe, n = 43) and healthy controls (n = 25). Brain tissues from CVA6-infected mice were examined using untargeted metabolomics. Several amino acids were significantly different between the three groups. Pathway analysis revealed that arginine, proline, and tryptophan metabolism are implicated in the pathogenesis of HFMD. A similar arginine depletion was observed in the brain tissues of CVA6-infected mice. Importantly, L-arginine supplementation improved the survival rate of CVA6-infected mice, inhibited virus multiplication, and reduced pathological autophagy associated with mTOR-autophagy pathway in the brain. Collectively, arginine, as the hub amino acid metabolite of the mammalian target of rapamycin (mTOR) signaling pathway affecting autophagy, plays an important role in the pathogenesis of severe HFMD. L-arginine supplementation may serve as a potential therapeutic option for critical patients with HFMD.

Childhood hand, foot and mouth disease sequelae cohort study in Henan, China: cohort profile

PURPOSE

The childhood hand, foot and mouth disease (HFMD) sequelae cohort study (HNHFMDCS) is an ambispective cohort study of patients with HFMD based in Henan Province, China, consisting of patients treated in a key hospital for the diagnosis and treatment of HFMD in Henan Province. The study aims to investigate the long-term sequelae of HFMD survivors and to provide a comprehensive understanding of the potential harm caused by this infectious disease.

PARTICIPANTS

In the retrospective phase of the cohort study, children diagnosed with HFMD from January 2014 to January 2023 were included, and clinical and demographic information about the patients was collected through a self-developed questionnaire. Patients hospitalised with HFMD since January 2023 were enrolled in the prospective cohort phase of the study, and long-term follow-up will be performed after completion of the baseline investigation (interview and comprehensive physical examination), clinical laboratory examination and biospecimen collection.

FINDINGS TO DATE

For the retrospective analysis of the cohort, a total of 18 705 HFMD cases (11 834 males and 6871 females) were observed between 2014 and 2022, of which 17 202 were mild cases (10 839 males and 6363 females) and 1503 were severe cases (995 males and 508 females). Statistical analysis was performed on the collected clinical examination data, and descriptive statistical methods, including mean value, SD and t-test, were used to compare the intergroup data. All tests were bilateral, and p<0.05 was considered statistically significant. There were significant differences in the hospitalisation duration and clinical examination indicators, such as platelets (PLT), C reactive protein (CRP), aspartate amino transferase (AST), alanine amino transferase (ALT), T lymphocyte subsets (CD3+ and CD3+CD4+) and B lymphocytes (CD19+) between mild and severe patients. The differences in these clinical examination indicators also help to detect changes in the disease in time so as to deeply understand the potential harm and social burden of the disease, and provide strong support for the rehabilitation of patients.

FUTURE PLANS

Prospective cohort studies are currently underway, primarily enrolling hospitalised patients with HFMD to participate in our study. After the baseline investigation is completed, we will conduct long-term follow-up of the enrolled cases. In the coming year, we expect to obtain preliminary data on the incidence of sequelae in patients with HFMD 1-10 years after discharge, as well as information on the occurrence of sequelae. This dataset will be updated and expanded on an annual basis to support the continuous monitoring of patient health and disease progression. From HNHFMDCS, the study will provide a comprehensive overview of the potential harm caused by this common infectious disease, assess the social burden caused by this disease and make recommendations for the rehabilitation of survivors and prevention of further disability.

Impact of early childhood infection on child development and school performance: a population-based study

BACKGROUND

Childhood infection might be associated with adverse child development and neurocognitive outcomes, but the results have been inconsistent.

METHODS

Two population-based record-linkage cohorts of all singleton children born at term in New South Wales, Australia, from 2001 to 2014, were set up and followed up to 2019 for developmental outcome (N=276 454) and school performance (N=644 291). The primary outcome was developmentally high risk (DHR) at age 4-6 years and numeracy and reading below the national minimum standard at age 7-9 years. Cox regression was used to assess the association of childhood infection ascertained from hospital records with each outcome adjusting for maternal, birth and child characteristics, and sensitivity analyses were conducted assessing E-values and sibling analysis for discordant exposure.

RESULTS

A higher proportion of children with an infection-related hospitalisation were DHR (10.9% vs 8.7%) and had numeracy (3.7% vs 2.7%) and reading results (4.3% vs 3.1%) below the national minimum standard, compared with those without infection-related hospitalisation. In the multivariable analysis, children with infection-related hospitalisation were more likely to be DHR (adjusted HR 1.12, 95% CI 1.08 to 1.15) and have numeracy (adjusted HR 1.22, 95% CI 1.18 to 1.26) and reading results (adjusted HR 1.16, 95% CI 1.12 to 1.20) below the national minimum standard. However, these results may be impacted by unmeasured confounding, based on E-values of 1.48-1.74, and minimal association with education outcome was found in the sibling analysis.

CONCLUSIONS

Infection-related hospitalisation was modestly associated with adverse child development and school performance, but the association may be explained by shared familial factors, particularly in those with most socioeconomic disadvantages.

Targeting Ser78 phosphorylation of Hsp27 achieves potent antiviral effects against enterovirus A71 infection

A positive-sense (+) single-stranded RNA (ssRNA) virus (e.g. enterovirus A71, EV-A71) depends on viral polypeptide translation for initiation of virus replication after entry. We reported that EV-A71 hijacks Hsp27 to induce hnRNP A1 cytosol redistribution to initiate viral protein translation, but the underlying mechanism is still elusive. Here, we show that phosphorylation-deficient Hsp27-3A (Hsp27S15/78/82A) and Hsp27S78A fail to translocate into the nucleus and induce hnRNP A1 cytosol redistribution, while Hsp27S15A and Hsp27S82A display similar effects to the wild type Hsp27. Furthermore, we demonstrate that the viral 2A protease (2Apro) activity is a key factor in regulating Hsp27/hnRNP A1 relocalization. Hsp27S78A dramatically decreases the IRES activity and viral replication, which are partially reduced by Hsp27S82A. However, Hsp27S15A displays the same activity as the wild-type Hsp27. Peptide S78 potently suppresses EV-A71 protein translation and reproduction through blockage of EV-A71-induced Hsp27 phosphorylation and Hsp27/hnRNP A1 relocalization. A point mutation (S78A) on S78 impairs its inhibitory functions on Hsp27/hnRNP A1 relocalization and viral replication. Taken together, we demonstrate the importance of Ser78 phosphorylation of Hsp27 regulated by virus infection in nuclear translocation, hnRNP A1 cytosol relocation, and viral replication, suggesting a new path (such as peptide S78) for target-based antiviral strategy.

The key mechanisms of multi-system responses triggered by central nervous system damage in hand, foot, and mouth disease severity

Hand, foot, and mouth disease (HFMD) is a prevalent infectious affliction primarily affecting children, with a small portion of cases progressing to neurological complications. Notably, in a subset of severe HFMD cases, neurological manifestations may result in significant sequelae and pose a risk of mortality. We systematically conducted literature retrieval from the databases PubMed (1957-2023), Embase (1957-2023), and Web of Science (1957-2023), in addition to consulting authoritative guidelines. Subsequently, we rigorously selected the most relevant articles within the scope of this review for comprehensive analysis. It is widely recognized that the severity of HFMD is attributed to a multifaceted array of pathophysiological mechanisms. The implication of multi-system dysfunction appears to be perturbances of the human defense system; therefore, it contributes to the severity of HFMD. In this review, we provide an overview and analysis of recent insights into the molecular mechanisms contributing to the severity of HFMD, with a particular focus on cytokine release syndrome, the involvement of the renin-angiotensin system, regional immunity, endothelial dysfunction, catecholamine storm, viral invasion, and the molecular mechanisms of neurological damage. We speculate that the domino effect of diverse physiological systems, initiated by damage to the central nervous system, serve as the primary mechanisms governing the severity of HFMD. Simultaneously, we emphasize the knowledge gaps and research urgently required to delineate a quick roadmap for ongoing and essential studies on HFMD.

Global landscape of coxsackieviruses in human health

Coxsackieviruses-induced infections, particularly in infants and young children, are one of the most important public health issues in low- and middle-income countries, where the surveillance system varies substantially, and these manifestations have been disregarded. They are widespread throughout the world and are responsible for a broad spectrum of human diseases, from mildly symptomatic conditions to severe acute and chronic disorders. Coxsackieviruses (CV) have been found to have 27 identified genotypes, with overlaps in clinical phenotypes between genotypes. In this review, we present a concise overview of the most recent studies and findings of coxsackieviruses-associated disorders, along with epidemiological data that provides comprehensive details on the distribution, variability, and clinical manifestations of different CV types. We also highlight the significant roles that CV infections play in the emergence of neurodegenerative illnesses and their effects on neurocognition. The current role of CVs in oncolytic virotherapy is also mentioned. This review provides readers with a better understanding of coxsackieviruses-associated disorders and pointing the impact that CV infections can have on different organs with variable pathogenicity. A deeper knowledge of these infections could have implications in designing current surveillance and prevention strategies related to severe CVs-caused infections, as well as encourage studies to identify the emergence of more pathogenic types and the etiology of the most common and most severe disorders associated with coxsackievirus infection.

Dual carminic acid/hemin-marked DNA probes for simultaneously detecting CV-A16 and EV-A71 based on the mechanism of dimer to monomer transition

This study aimed to prepare two hairpin-structure DNA probes by conjugating carminic acid (CA) or hemin into two ends of specific genes of coxsackievirus A16 (CV-A16) and enterovirus A71 (EV-A71) (probe_CV-A16-CA and probe_EV-A71-hemin). Then, probe_CV-A16-CA and probe_EV-A71-hemin as the signal molecules were adsorbed onto NH₂-MIL-53 (Al) (MOF). Based on these biocomposites, an electrochemical biosensor with dual-signal outputs for simultaneous assay of CV-A16 and EV-A71 was constructed. The stem-loops of probes switched both CA and hemin monomer to dimer, reducing the electrical activity of both CA and hemin. Subsequently, the target-induced opening of the stem-loop switched both CA and hemin dimers to monomers, resulting in two nonoverlapping increasing electrical signals. This sensitively reflected the concentration of target_CV-A16 and target_EV-A17 ranging from 10^-10 to 10^-15 M with a detection limit of 0.19 and 0.24 fM. This strategy was mainly applied to the simultaneous determination of target_CV-A16 and target_EV-A17 in 100% serum with satisfactory results. The MOF combined with the high loading capacity broke through the intrinsic limitation on sensitivity using the traditional methods. An increase of three orders of magnitude was observed. This study involved simple one-step detection, and only a simple replacement of a gene could trigger its potential in clinical and diagnostic applications.

Current status of hand-foot-and-mouth disease

Hand-foot-and-mouth disease (HFMD) is a viral illness commonly seen in young children under 5 years of age, characterized by typical manifestations such as oral herpes and rashes on the hands and feet. These symptoms typically resolve spontaneously within a few days without complications. Over the past two decades, our understanding of HFMD has greatly improved and it has received significant attention. A variety of research studies, including epidemiological, animal, and in vitro studies, suggest that the disease may be associated with potentially fatal neurological complications. These findings reveal clinical, epidemiological, pathological, and etiological characteristics that are quite different from initial understandings of the illness. It is important to note that HFMD has been linked to severe cardiopulmonary complications, as well as severe neurological sequelae that can be observed during follow-up. At present, there is no specific pharmaceutical intervention for HFMD. An inactivated Enterovirus A71 (EV-A71) vaccine that has been approved by the China Food and Drug Administration (CFDA) has been shown to provide a high level of protection against EV-A71-related HFMD. However, the simultaneous circulation of multiple pathogens and the evolution of the molecular epidemiology of infectious agents make interventions based solely on a single agent comparatively inadequate. Enteroviruses are highly contagious and have a predilection for the nervous system, particularly in child populations, which contributes to the ongoing outbreak. Given the substantial impact of HFMD around the world, this Review synthesizes the current knowledge of the virology, epidemiology, pathogenesis, therapy, sequelae, and vaccine development of HFMD to improve clinical practices and public health efforts.

'Tomato flu' a new epidemic in India: Virology, epidemiology, and clinical features

This article aims to highlight the current update on the 'tomato flu' outbreak in India. Recently there was an outbreak of a new illness in some parts of India. The disease was very contagious and it manifested with a rash mainly noticed in children younger than nine years. The rash was very painful and blisters were the size of small tomatoes, hence it was termed 'tomato flu'. A detailed literature review was performed on the virology, replication, epidemiology, and clinical features of this disease. The current outbreak was compared with similar other diseases of the past. The affected children exhibited severe rash in the palms, soles, oral cavity, and other body parts. They developed febrile illness with a sore throat, and myalgia followed by blisters on the tongue, gums, and cheeks. The affected children did not develop any complications leading to death. The therapy involved mainly symptomatic, supportive treatment with isolation and maintaining hygienic practices. The causative agent was identified to be Coxsackievirus A16, an RNA virus belonging to the family, Picornaviridae. We conclude that the recent Indian epidemic of this disease might be due to a new variant of Coxsackievirus A16 actually causing HFMD.

Association between pulmonary ventilatory function and mild cognitive impairment: A population-based study in rural China

Background

Mild cognitive impairment (MCI), a reversible intermediate state, plays an important role in the development and prevention of dementia. The relationship between pulmonary function and MCI risk has not yet been well-elucidated.

Methods

We included 2,947 rural Chinese residents aged ≥35 years who were free from a history of stroke, dementia, or other brain diseases and measured pulmonary ventilatory function using calibrated spirometry according to the recommended method. MCI was assessed with the Montreal Cognitive Assessment-Basic for Chinese scale. Logistic regression models and restricted cubic splines with covariate adjustment were performed to explore the association between pulmonary function and MCI risk.

Results

The prevalence of MCI increased with decreasing pulmonary function, from the lowest quartile to the highest quartile of pulmonary function: 63.9, 50.5, 43.8, and 43.6%, respectively. After adjustment for confounding factors, participants in the first quartile had a significantly increased risk of MCI (ORs, 1.691, 95% CI, 1.267-2.258), with the highest quartile as the reference. In the subgroup analysis, a significant association of pulmonary function and MCI was found in females and those with low physical activity. Meanwhile, we observed an L-shaped relationship between pulmonary function and MCI (P _non-linear = 0.032).

Conclusions

Poor pulmonary function was associated with an increased risk of MCI among rural Chinese adults, and presented a non-linear relationship. These findings remind us of the need for early cognitive assessment in local populations with lower pulmonary function.

Hand, Foot, and Mouth Disease: A Narrative Review

BACKGROUND

Hand, foot, and mouth disease is a common viral disease in childhood. Because the disease has the potential to reach epidemic levels and mortality is high in some countries, early recognition of this disease is of paramount importance.

OBJECTIVE

This purpose of this article is to familiarize pediatricians with the clinical manifestations and management of hand, foot, and mouth disease.

METHODS

A search was conducted in February 2022 in PubMed Clinical Queries using the key term "hand, foot, and mouth disease". The search strategy included all clinical trials, observational studies, and reviews published within the past 10 years. Only papers published in English were included in this review.

RESULTS

Hand, foot, and mouth disease is characterized by a painful oral enanthem and asymptomatic exanthem on the palms and soles. Children younger than 5 years are most commonly affected. Hand, foot, and mouth disease caused by enterovirus A71 is more severe and has a higher rate of complications than that attributed to other viruses such as coxsackievirus A16. Circulatory failure secondary to myocardial impairment and neurogenic pulmonary edema secondary to brainstem damage are the main causes of death. Fortunately, the disease is usually benign and resolves in 7 to10 days without sequelae. Given the self-limited nature of most cases, treatment is mainly symptomatic and supportive. Intravenous immunoglobulin should be considered for the treatment of severe/complicated hand, foot, and mouth disease and has been recommended by several national and international guideline committees. Currently, there are no specific antiviral agents approved for the treatment of the disease. Drugs such as ribavirin, suramin, mulberroside C, aminothiazole analogs, and sertraline have emerged as potential candidates for the treatment of hand, foot, and mouth disease. Vaccination of susceptible individuals in high-risk areas and good personal hygiene are important preventative measures to combat the disease.

CONCLUSION

Familiarity of the disease including its atypical manifestations is crucial so that a correct diagnosis can be made, and appropriate treatment initiated. A timely diagnosis can help avoid contact with the affected individual and decrease the risk of an outbreak.

A single mutation in the cis-acting replication element identified within the EV-A71 2C-coding region causes defects in virus production in cell culture

ABSTRACTEnterovirus A71 (EV-A71) can cause hand, foot and mouth disease with neurological and systemic complications, most frequently affecting children and infants. We describe a cis-acting replication element (cre) with a conserved stem-loop structure within the EV-A71 2C-coding region. By site-directed mutagenesis and reverse genetics using the EV-A71 full-length genome and the EV-A71 replicon containing the firefly luciferase reporter gene in place of the P1 region, the stem-loop structure and the AAACA in the loop of the cre were confirmed to be required for the EV-A71 replication phenotype. EV-A71 genomes containing a mutation at the first or third A residue of AAACA could not be recovered. Insertion of a wild-type cre from EV-A71 or poliovirus in the 5'UTR led to successful recovery of the replication of nonviable mutants. Furthermore, the cre mutants showed lower binding capacity with the host cellular factor IGF2BP2, knockdown of which resulted in a significant decrease in EV-A71 production. All the available evidence shows the location independence but functional importance of the interaction of the cre with the cellular host for efficient production of EV-A71, contributing to the growing body of knowledge regarding picornavirus cres.

Implications of Innate Immunity in Post-Acute Sequelae of Non-Persistent Viral Infections

Non-persistent viruses classically cause transient, acute infections triggering immune responses aimed at the elimination of the pathogen. Successful viruses evolved strategies to manipulate and evade these anti-viral defenses. Symptoms during the acute phase are often linked to dysregulated immune responses that disappear once the patient recovers. In some patients, however, symptoms persist or new symptoms emerge beyond the acute phase. Conditions resulting from previous transient infection are termed post-acute sequelae (PAS) and were reported for a wide range of non-persistent viruses such as rota-, influenza- or polioviruses. Here we provide an overview of non-persistent viral pathogens reported to be associated with diverse PAS, among them chronic fatigue, auto-immune disorders, or neurological complications and highlight known mechanistic details. Recently, the emergence of post-acute sequelae of COVID-19 (PASC) or long COVID highlighted the impact of PAS. Notably, PAS of non-persistent infections often resemble symptoms of persistent viral infections, defined by chronic inflammation. Inflammation maintained after the acute phase may be a key driver of PAS of non-persistent viruses. Therefore, we explore current insights into aberrant activation of innate immune signaling pathways in the post-acute phase of non-persistent viruses. Finally, conclusions are drawn and future perspectives for treatment and prevention of PAS are discussed.