Cost-effectiveness of bivalent versus monovalent vaccines against hand, foot and mouth disease

Intranasal immunization with curdlan induce Th17 responses and enhance protection against enterovirus 71

Mucosal surfaces are in contact with the external environment and protect the body from infection by various microbes. To prevent infectious diseases at the first line of defense, the establishment of pathogen-specific mucosal immunity by mucosal vaccine delivery is needed. Curdlan, a 1,3-β-glucan has a strong immunostimulatory effect when delivered as a vaccine adjuvant. Here, we investigated whether intranasal administration of curdlan and antigen (Ag) could induce sufficient mucosal immune responses and protect against viral infections. Intranasal co-administration of curdlan and OVA increased OVA-specific IgG and IgA Abs in both serum and mucosal secretions. In addition, intranasal co-administration of curdlan and OVA induced the differentiation of OVA-specific Th1/Th17 cells in the draining lymph nodes. To investigate the protective immunity of curdlan against viral infection, intranasal co-administration of curdlan with recombinant VP1 of EV71 C4a was administered and showed enhanced protection against enterovirus 71 in a passive serum transfer model using neonatal hSCARB2 mice, although intranasal administration of VP1 plus curdlan increased VP1-specific helper T cells responses but not mucosal IgA. Next, Mongolian gerbils were intranasally immunized with curdlan plus VP1, and they had effective protection against EV71 C4a infection, while decreasing viral infection and tissue damage by inducing Th17 responses. These results indicated that intranasal curdlan with Ag improved Ag-specific protective immunity by enhancing mucosal IgA and Th17 against viral infection. Our results suggest that curdlan is an advantageous candidate as a mucosal adjuvant and delivery vehicle for the development of mucosal vaccines.

Study on the interaction between different pathogens of Hand, foot and mouth disease in five regions of China

Objectives

This study aims to explore the interaction of different pathogens in Hand, foot and mouth disease (HFMD) by using a mathematical epidemiological model and the reported data in five regions of China.

Methods

A cross-regional dataset of reported HFMD cases was built from four provinces (Fujian Province, Jiangsu province, Hunan Province, and Jilin Province) and one municipality (Chongqing Municipality) in China. The subtypes of the pathogens of HFMD, including Coxsackievirus A16 (CV-A16), enteroviruses A71 (EV-A71), and other enteroviruses (Others), were included in the data. A mathematical model was developed to fit the data. The effective reproduction number (R _eff ) was calculated to quantify the transmissibility of the pathogens.

Results

In total, 3,336,482 HFMD cases were collected in the five regions. In Fujian Province, the R _eff between CV-A16 and EV-A71&CV-A16, and between CV-A16 and CV-A16&Others showed statistically significant differences (P < 0.05). In Jiangsu Province, there was a significant difference in R _eff (P < 0.05) between the CV-A16 and Total. In Hunan Province, the R _eff between CV-A16 and EV-A71&CV-A16, between CV-A16 and Total were significant (P < 0.05). In Chongqing Municipality, we found significant differences of the R _eff (P < 0.05) between CV-A16 and CV-A16&Others, and between Others and CV-A16&Others. In Jilin Province, significant differences of the R _eff (P < 0.05) were found between EV-A71 and Total, and between Others and Total.

Conclusion

The major pathogens of HFMD have changed annually, and the incidence of HFMD caused by others and CV-A16 has surpassed that of EV-A71 in recent years. Cross-regional differences were observed in the interactions between the pathogens.

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.

[Epidemiological and etiological characteristics of hand, foot and mouth disease among children aged 5 years and younger in Ningbo (2016 to 2019)]

OBJECTIVE

To describe the epidemiological and etiological characteristics of hand, foot and mouth disease (HFMD) among children aged 5 years and younger in Ningbo after the access of entero-virus-A71 vaccine (2016 to 2019).

METHODS

A retrospective cohort study were performed in children aged 5 years and younger in Ningbo from 2016 to 2019. Data for incidence of HFMD was collected from the National Notifiable Disease Surveillance Reporting System and the Electronic Medical Records (EMRs) System, while the demographic information was derived from the Immunization Information System. Speci-mens were detected by real-time fluorescence quantitative PCR and the Wilson method was used to estimate the incidence rate and 95% confidence interval.

RESULTS

From 2016 to 2019, a total of 1 044 800 residential children were observed in this population-based cohort. In the study, 102 471 cases of HFMD were diagnosed in 2 651 081 person-years, revealing an overall incidence density of 3 865.25/100 000 person-years. There was no significant decline in the number of the cases after the vaccine was available. The number of the patients of hand foot mouth disease during the four years was 93 421, of whom 84 875 (90.85%) had only one incident record, while 8 946 (9.15%) had 2 or more cases in this period; there were 69 771 (66.06%) patients who only needed to see a doctor once for each disease, 19.92% of the patients needed to be treated twice, and 14 801 (14.02%) patients needed to go to the hospital or clinic three times or more. The incidence of HFMD showed obvious seasonality and periodicity, which mainly concentrated in April to July each year, and the epidemic cycle was 2 years; most of the cases were 1 to 3-year old children, with more cases in male. The incidence density varied across the region, with the highest density observed in Ninghai (4 524.76/100 000 person-years), followed by Xiangshan (3 984.22/100 000 person-years). In 3 748 library-conformed cases, 2 834(75.61%) were detected positive, among which enterovirus-A71, Cox-A16 and other enteroviruses accounted for 9.03%, 31.55% and 59.42%, respectively. During the study period, the cumulative coverage of enterovirus-A71 vaccine increased year by year, with the proportion of enterovirus-A71 and severe cases both gradually decreasing.

CONCLUSION

The current status of hand, foot and mouth disease in Ningbo is still serious. Children under 3-year old (especially male children aged 1 year) were the key population for prevention and control. Vaccination might lead to changes in major pathogenic virus type, of which more attention should be paid to the potential impact on disease surveillance, prevention and control.

[Epidemiological and etiological characteristics of hand, foot and mouth disease among children aged 5 years and younger in Ningbo (2016 to 2019)]

OBJECTIVE

To describe the epidemiological and etiological characteristics of hand, foot and mouth disease (HFMD) among children aged 5 years and younger in Ningbo after the access of entero-virus-A71 vaccine (2016 to 2019).

METHODS

A retrospective cohort study were performed in children aged 5 years and younger in Ningbo from 2016 to 2019. Data for incidence of HFMD was collected from the National Notifiable Disease Surveillance Reporting System and the Electronic Medical Records (EMRs) System, while the demographic information was derived from the Immunization Information System. Speci-mens were detected by real-time fluorescence quantitative PCR and the Wilson method was used to estimate the incidence rate and 95% confidence interval.

RESULTS

From 2016 to 2019, a total of 1 044 800 residential children were observed in this population-based cohort. In the study, 102 471 cases of HFMD were diagnosed in 2 651 081 person-years, revealing an overall incidence density of 3 865.25/100 000 person-years. There was no significant decline in the number of the cases after the vaccine was available. The number of the patients of hand foot mouth disease during the four years was 93 421, of whom 84 875 (90.85%) had only one incident record, while 8 946 (9.15%) had 2 or more cases in this period; there were 69 771 (66.06%) patients who only needed to see a doctor once for each disease, 19.92% of the patients needed to be treated twice, and 14 801 (14.02%) patients needed to go to the hospital or clinic three times or more. The incidence of HFMD showed obvious seasonality and periodicity, which mainly concentrated in April to July each year, and the epidemic cycle was 2 years; most of the cases were 1 to 3-year old children, with more cases in male. The incidence density varied across the region, with the highest density observed in Ninghai (4 524.76/100 000 person-years), followed by Xiangshan (3 984.22/100 000 person-years). In 3 748 library-conformed cases, 2 834(75.61%) were detected positive, among which enterovirus-A71, Cox-A16 and other enteroviruses accounted for 9.03%, 31.55% and 59.42%, respectively. During the study period, the cumulative coverage of enterovirus-A71 vaccine increased year by year, with the proportion of enterovirus-A71 and severe cases both gradually decreasing.

CONCLUSION

The current status of hand, foot and mouth disease in Ningbo is still serious. Children under 3-year old (especially male children aged 1 year) were the key population for prevention and control. Vaccination might lead to changes in major pathogenic virus type, of which more attention should be paid to the potential impact on disease surveillance, prevention and control.

Leading Enterovirus Genotypes Causing Hand, Foot, and Mouth Disease in Guangzhou, China: Relationship with Climate and Vaccination against EV71

(1) Background: Assignment of pathogens to the correct genus, species, and type is vital for controlling infectious epidemics. However, the role of different enteroviruses during hand, foot, and mouth disease (HFMD) epidemics and the major contributing factors remain unknown. (2) Methods: HFMD cases from 2016 to 2018 in Guangzhou, China were collected. The relationship between HFMD cases and genotype frequency, as well as the association between genotype frequency and climate factors, were studied using general linear models. We transformed the genotype frequency to the isometric log-ratio (ILR) components included in the model. Additionally, vaccination rates were adjusted in the climate-driven models. (3) Results: We observed seasonal trends in HFMD cases, genotype frequency, and climate factors. The model regressing case numbers on genotype frequency revealed negative associations with both the ILRs of CAV16 (RR = 0.725, p < 0.001) and EV71 (RR = 0.421, p < 0.001). The model regressing genotype frequency on driven factors showed that the trends for EV71 proportions were inversely related to vaccination rate (%, β = -0.152, p = 0.098) and temperature (°C, β = -0.065, p = 0.004). Additionally, the trends for CVA16 proportions were inversely related to vaccination rate (%, β = -0.461, p = 0.004) and temperature (°C, β = -0.068, p = 0.031). The overall trends for genotype frequency showed that EV71 decreased significantly, while the trends for CVA16 increased annually. (4) Conclusions: Our findings suggest a potential pathway for climate factors, genotype frequency, and HFMD cases. Our study is practical and useful for targeted prevention and control, and provides environmental-based evidence.

Prognostic Value of Neutrophil-to-Lymphocyte Ratio in Predicting Death Risk in Patients with Severe Hand, Foot and Mouth Disease

Introduction

Severe hand, foot, and mouth disease (HFMD) may lead to serious complications, which cause child mortality during outbreaks. The aim of this study was to determine whether neutrophil-to-lymphocyte ratio (NLR) can predict death risk in severe HFMD.

Methods

Medical records for 664 severe HFMD patients were retrospectively examined, and NLR was calculated from blood counts. Youden’s index was calculated to determine the optimal NLR cutoff. Uni- and multivariate logistic regression were used to determine death risk factors associated with severe HFMD.

Results

An NLR cutoff value of 2.01 and 2.50 respectively predicted mortality among all 664 severe HFMD and 137 critical HFMD. Among all 664 patients, the multivariate model identified the following as independently associated with death risk: high fever (OR 3.342, 95% CI 1.736–6.432), EV71 infection (OR 3.200, 95% CI 1.529–6.698), fasting glucose (OR 37.343, 95% CI 18.616–74.909), and NLR (>2.01) (OR 2.142, 95% CI 1.125–4.079). Among 137 critical HFMD, EV71 infection (OR 3.441, 95% CI 1.132–10.462), fasting glucose (OR 14.173, 95% CI 4.920–40.827), and NLR (>2.50) (OR 4.166, 95% CI 1.570–11.051) were associated with death risk.

Conclusion

In conclusion, NLR (>2.01) in severe HFMD and NLR (>2.50) in critical HFMD patients may be associated with increased death risk.

Clinical, etiological and epidemiological investigations of hand, foot and mouth disease in southern Vietnam during 2015 - 2018

Hand, foot and mouth disease (HFMD) continues to challenge Asia with pandemic potential. In Vietnam, there have been two major outbreaks occurring during 2011-2012 (>200,000 hospitalizations and >200 deaths) and more recently in 2018 (>130,000 hospitalizations and 17 deaths). Given the high burden and the complex epidemic dynamics of HFMD, synthesizing its clinical and epidemiological data remains essential to inform the development of appropriate interventions and design public health measures. We report the results of a hospital-based study conducted during 2015-2018, covering the severe HFMD outbreak recently documented in Vietnam in 2018. The study was conducted at three major hospitals responsible for receiving HFMD patients from southern Vietnam with a population of over 40 million. A total of 19 enterovirus serotypes were detected in 1196 HFMD patients enrolled in the clinical study during 2015-2018, with enterovirus A71 (EV-A71), coxsackievirus A6 (CV-A6), CV-A10 and CV-A16 being the major causes. Despite the emergence of coxsackieviruses, EV-A71 remains the leading cause of severe HFMD in Vietnam. EV-A71 was consistently detected at a higher frequency during the second half of the years. The emergence of EV-A71 subgenogroup C4 in late 2018 was preceded by its low activity during 2017-early 2018. Compared with EV-A71 subgenogroup B5, C4 was more likely to be associated with severe HFMD, representing the first report demonstrating the difference in clinical severity between subgenogroup C4 and B5, the two predominant EV-A71 subgenogroups causing HFMD worldwide. Our data have provided significant insights into important aspects of HFMD over four years (2015-2018) in Vietnam, and emphasize active surveillance for pathogen circulation remains essential to inform the local public health authorities in the development of appropriate intervention strategies to reduce the burden of this emerging infections. Multivalent vaccines are urgently needed to control HFMD.