Comparison of Nonpolio Enteroviruses in Children With Herpangina and Hand, Foot and Mouth Disease in Taiwan

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.

Hand, foot, and mouth disease: could EPs® 7630 be a treatment option? A prospective randomized open-label multicenter clinical study

Purpose

Hand, foot and mouth disease (HFMD) is a viral contagious disease of children caused by human enteroviruses (EVs) and coxsackieviruses (CVs). There is no specific treatment option for HFMD. EPs® 7630's anti-infective and immunomodulatory properties have previously been demonstrated in several in vitro and in vivo studies; however, the use of this herbal medicine in children with HFMD has not previously been investigated.

Methods

This prospective randomized multicenter clinical study included 208 children with HFMD. The diagnosis was made by pediatricians. The patients who were within the first 48 h of symptom onset (according to the first onset of fever and skin findings) were enrolled. The study participants were assigned into 2 groups as EPs® 7630 and control groups. All patients were followed up twice more, 48 h after the first admission and on the 5th-7th day. Another phone evaluation was conducted for those with continued complaints from the previous visit.

Results

The median age was 27 (12-112) months. The male-female ratio was 0.98. One hundred thirty one (63%) of 190 patients had no history of household contact. EPs® 7630 group included 94 and control group included 96 patients. A significant difference was found between the groups in terms of complaint scores at the visits made at the 48th h of the treatment and on days 5-7 (p < 0.001). The mean ± SD disease duration of EPs® 7630 users was significantly shorter 6.07 ± 0.70 days (95% CI: 5.92-6.21)] than the control group [8.58 ± 0.94 days (95% CI: 8.39-8.77)] (p < 0.001). Besides, the hospitalization rate among the EPs® 7630 users were significantly lower (p = 0.019). No side effects were observed, except for unpleasant taste, which was reported in 5 patients (EPs® 7630 group).

Conclusion

Considering its efficacy and safety profile EPs® 7630 may represent a feasible herbal-based treatment option for children with HFMD.

Clinical Trial Registration

ClinicalTrials.gov, identifier (NCT06353477).

Seasonal Testing, Results, and Effect of the Pandemic on Coxsackievirus Serum Studies

Coxsackieviruses (CVs) are common causes of infections and can be life-threatening. Unfortunately, rigorous studies guiding the clinician in interpreting CV serum antibody titer testing is lacking. To explore the epidemiology of circulating CVs and the serological test utility in aiding diagnosis of CV infections in our community, we obtained results of CV immunologic diagnostic tests between 2018 and 2022 from a regional healthcare database. For CV type A, rare individuals had positive CF (complement fixation) tests whereas all 16 individuals with IFA testing showed at least one positive serotype. For CV type B CF testing, 52.2% of 222 patients had at least one serotype positive, with B5 being most common and also the most common with higher titers (14.8% with ≥1:32). We found a significant reduction in seropositivity rate during the pandemic in 2020 compared to 2018, which continued through 2022 (OR: 0.2, 95% CI: 0.08-0.49, p-value < 0.001). During the pandemic, the seasonal pattern of positive tests varied from the pre-pandemic pattern. Testing for CVs was increased after the first year of the pandemic. Overall, the variability by month and seasonal change in our data support that CF testing can be used to identify recent CVB infection.

Genetic and Cross Neutralization Analyses of Coxsackievirus A16 Circulating in Taiwan from 1998 to 2021 Suggest Dominant Genotype B1 can Serve as Vaccine Candidate

Coxsackievirus A16 (CVA16) is well known for causing hand-foot-and-mouth disease (HFMD) and outbreaks were frequently reported in Taiwan in the past twenty years. The epidemiology and genetic variations of CVA16 in Taiwan from 1998 to 2021 were analyzed in this study. CVA16 infections usually occurred in early summer and early winter, and showed increased incidence in 1998, 2000-2003, 2005, 2007-2008, and 2010 in Taiwan. Little or no CVA16 was detected from 2017 to 2021. CVA16 infection was prevalent in patients between 1 to 3 years old. A total of 69 isolates were sequenced. Phylogenetic analysis based on the VP1 region showed that CVA16 subgenotype B1 was dominantly isolated in Taiwan from 1998 to 2019, and B2 was identified only from isolates collected in 1999 and 2000. There was a high frequency of synonymous mutations in the amino acid sequences of the VP1 region among CVA16 isolates, with the exception of position 145 which showed positive selection. The recombination analysis of the whole genome of CVA16 isolates indicated that the 5'-untranslated region and the non-structural protein region of CVA16 subgenotype B1 were recombined with Coxsackievirus A4 (CVA4) and enterovirus A71 (EVA71) genotype A, respectively. The recombination pattern of subgenotype B2 was similar to B1, however, the 3D region was similar to EVA71 genotype B. Cross-neutralization among CVA16 showed that mouse antisera from various subgenotypes viruses can cross-neutralize different genotype with high neutralizing antibody titers. These results suggest that the dominant CVA16 genotype B1 can serve as a vaccine candidate for CVA16.

Molecular surveillance of coxsackievirus A16 in southern China, 2008-2019

A national surveillance system on hand, foot, and mouth disease (HFMD) was launched in 2008 in China. Since then, millions of HFMD cases have been reported each year, with enterovirus A71 (EV-A71), coxsackievirus A16 (CV-A16), and coxsackievirus A6 (CV-A6) as the major causative pathogens. Long-term surveillance of viral infection rates and genetic changes is essential for understanding the disease epidemiology pattern. Here, we analyzed molecular surveillance data on CV-A16 covering a period of 12 years (2008-2019) in Guangdong, China, one of the regions reporting the largest number of HFMD cases. Full VP1 sequences of 456 strains were determined to examine the genetic diversity and changes in the distribution of CV-A16 variants. Our study revealed an irregular pattern of CV-A16 infections in Guangdong. Different from the cyclic epidemics observed in some Asia-Pacific regions, there was a continuously high CV-A16 infection rate from 2008 to 2014, and after a period of lower epidemic activity in 2015-2017, an upsurge of CV-A16 infection was observed in 2018-2019. Cocirculation of subgenotypes B1a and B1b was observed, but while subgenotype B1a was predominant from 2008 to 2012, it appears to have been replaced by B1b, which has circulated as the predominant subgenotype since 2013. Phylogenetic analysis showed that most of the circulating CV-A16 strains are endemic, with occasional transmission between neighboring regions. The re-emergence of B1a in 2016-2019 in Guangdong was likely the result of introduction(s) from Southeast Asia. These results highlight the importance of continuous molecular surveillance from different areas, which will improve our understanding of the origin of the epidemic and facilitate the development of strategies for HFMD disease control.

Time-dependent associations between presentation-based infections and subsequent risk of childhood immune cell malignancies

BACKGROUND

Infection is hypothesised as a contributory cause of childhood immune cell malignancies. Although some have reported associations between individual infections and immune cell malignancies, some could be spurious due to infections caused by malignancies that were already active prior to diagnosis.

METHODS

Identified from Taiwan Cancer Registry, ∼3000 children with four commonest immune cell malignancies diagnosed during 2001-2015 at age 1-20 years were identified and matched with 1:10 controls. Using logistic regression, we estimated the time-specific case-versus-control odds ratios of seven common infection presentations in their health records. We also compared recorded unexplained lymph nodes between cases and controls to explore for how long malignancy may be active prior to diagnosis.

RESULTS

Unexplained lymph nodes were increasingly recorded months before the diagnosis of childhood leukaemias and years before the diagnosis of childhood lymphomas. When using p < 0.01 as a guide, large case-control differences in infection records were found mostly within 0-2 months prior to the diagnosis (15 out of 28 comparisons). Changes in odds ratios within 3-35 months (2 out of 28 comparisons) and case-control differences beyond 36+ months prior to diagnosis (7 out of 28 comparisons) was relatively small (∼10 % difference in leukaemias). Statistical power varied according to incidence of malignancy, incidence of infection records, and the age distribution.

CONCLUSION

Immune cell malignancies were likely to be active some time before the diagnosis. Previous studies using conventional population-based methods may not be able to distinguish any small causal link between infection and immune cell malignancies from spurious associations.