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.

A 4-year-old boy presented with asymmetric acute flaccid paralysis (AFP) of his right arm and both legs. He was alert with no oculobulbar weakness or incontinence. He had fever and diarrhea 5 days earlier. He was fully immunized with no travel history.

Pakistan is at the verge of polio eradication but isolation of non-polio enteroviruses (NPEVs) from acute flaccid paralysis (AFP) cases may result in serious or even fatal outcome. Many enteroviruses share similar symptoms and epidemiology as is the case with poliovirus and coxsackievirus (CV). The present study was designed to genetically characterize coxsackievirus B (CV-B) serotypes isolated from non-polio acute flaccid paralytic children, as well as to understand their probable role in paralysis. A total of 63 (20·1%) out of 313 stool samples during 2013 were found positive for NPEVs in rhabdomyosarcoma cells. Only 24 (38·0%) NPEVs were typed as CV-B by microneutralization assay and were further characterized by sequencing of the viral protein 1 (VP1) gene. Molecular phylogenetic analyses classified the study strains into six coxsackievirus B serotypes (coxsackievirus B1 to B6) with their respective prototype strains with evidence of epidemiological linkage and distinct clusters. Moreover, four major differences were found within the amino acid sequences of BC-loop in VP1 of CV-B strains. In conclusion, this study presented the molecular evolutionary genetic overview and distinct phylogenetic pattern of CV-B isolates from AFP cases in Pakistan, and explored the possible link between CV-B infections and AFP cases. Furthermore, our data reveal that these viruses might contribute to the incidence of paralysis in population and there is need of time to establish an enterovirus surveillance system for better understanding of epidemiological and virological characteristics of NPEV infections associated with AFP cases in the country.

Over the past 8 years, human enteroviruses (HEVs) have caused 27 227 cases of hand, foot and mouth disease (HFMD) in Xiamen, including 99 severe cases and six deaths. We aimed to explore the molecular epidemiology of HFMD in Xiamen to inform the development of diagnostic assays, vaccines and other interventions. From January 2009 to September 2015, 5866 samples from sentinel hospitals were tested using nested reverse transcription PCR that targeted the HEV 5′ untranslated region and viral protein 1 region. Of these samples, 4290 were tested positive for HEV and the amplicons were sequenced and genotyped. Twenty-two genotypes were identified. Enterovirus 71 (EV71) and coxsackieviruses A16, A6 and A10 (CA16, CA6 and CA10) were the most common genotypes, and there were no changes in the predominant lineages of these genotypes. EV71 became the most predominant genotype every 2 years. From 2013, CA6 replaced CA16 as one of the two most common genotypes. The results demonstrate the vast diversity of HFMD pathogens, and that minor genotypes are able to replace major genotypes. We recommend carrying-out long-term monitoring of the full spectrum of HFMD pathogens, which could facilitate epidemic prediction and the development of diagnostic assays and vaccines.

The community burden of enterovirus is often monitored through syndromic monitoring systems based on reported cases of enterovirus-related infection (EVI) diagnoses. The extent to which this is affected by under- and over-diagnosis has not been reported. In Taiwan, children often make more than one healthcare visit during an episode of infection. We used change of diagnosis within an episode of infection as a guide of diagnostic uncertainty in a nationally representative cohort of Taiwanese children (n = 13 284) followed from birth to the 9th birthday through electronic health records. We conducted a nested case-control analysis and estimated cross-diagnosis ratios (CDRs) as the observed proportion of acute respiratory infection (ARI) diagnoses following an EVI diagnosis in excess of background ARI burdens. With 19 357 EVI diagnoses in this cohort, the CDR within 7 days was 1·51 (95% confidence interval 1·45–1·57), confirming a significant excess of ARI diagnoses within the week following an EVI diagnosis. We used age-specific CDRs to calibrate the weekly EVI burden in children aged 3–5 years in 2008, and the difference between observed and calibrated weekly EVI burdens was small. Therefore, there was evidence suggesting a small uncertainty in EVI diagnosis, but the observed EVI burdens through syndromic monitoring were not substantially affected by the small uncertainty.

Coxsackievirus A6 (CV-A6), coxsackievirus A16 (CV-A16) and enterovirus 71 (EV-A71) were the major enteroviruses causing nationwide hand, foot and mouth disease (HFMD) epidemics in Singapore in the last decade. We estimated the basic reproduction number (R0) of these enteroviruses to obtain a better understanding of their transmission dynamics. We merged records of cases from HFMD outbreaks reported between 2007 and 2012 with laboratory results from virological surveillance. R0 was estimated based on the cumulative number of reported cases in the initial growth phase of each outbreak associated with the particular enterovirus type. A total of 33 HFMD outbreaks were selected based on the inclusion criteria specified for our study, of which five were associated with CV-A6, 13 with CV-A16, and 15 with EV-A71. The median R0 was estimated to be 5·04 [interquartile range (IQR) 3·57–5·16] for CV-A6, 2·42 (IQR 1·85–3·36) for CV-A16, and 3·50 (IQR 2·36–4·53) for EV-A71. R0 was not significantly associated with number of infected children (P = 0·86), number of exposed children (P = 0·94), and duration of the outbreak (P = 0·05). These enterovirus-specific R0 estimates will be helpful in providing insights into the potential growth of future HFMD epidemics and outbreaks for timely implementation of disease control measures, together with disease dynamics such as severity of the cases.

Acute haemorrhagic conjunctivitis outbreaks are often attributed to viral infection. In 2014, an unprecedented nationwide outbreak of infectious conjunctivitis occurred in Thailand, which affected >300 000 individuals over 3 months. To identify and characterize the virus responsible for the epidemic, eye swab specimens from 119 patients were randomly collected from five different provinces. Conserved regions in the enteroviral 5′-UTR and adenovirus hexon gene were analysed. Enterovirus was identified in 71·43% (85/119) of the samples, while no adenovirus was detected. From enterovirus-positive samples, the coxsackievirus A24 variant (70·59%, 84/119) and echovirus (0·84%, 1/119) were identified. Additional sequencing of full-length VP1 and 3C genes and subsequent phylogenetic analysis revealed that these clinical isolates form a new lineage cluster related to genotype IV-C5. In summary, the coxsackievirus A24 variant was identified as an aetiological agent for the recent acute haemorrhagic conjunctivitis outbreak in Thailand.

Intra-home and kindergarten transmissions were the reported major modes of hand, foot, and mouth disease (HFMD) transmission in preschool children. However, infection at home is not common and 65–80% of cases do not attend preschool. We conducted a matched case-control study to explore the role of public playgrounds in the transmission of HFMD in addition to direct and indirect exposure to HFMD patients. We used 156 hospital source cases and 156 community source controls. Univariate analysis was followed by conditional logistic regression with attributable fraction computed. Adjusted odds ratios were 11·70 [95% confidence interval (CI) 1·26–109·40] for having HFMD cases in the same class, 14·19 (95% CI 3·55–56·74) for having HFMD cases within the 20 nearest neighbourhoods, 6·03 (95% CI 2·84–12·80) for exposure to public playgrounds, 2·13 (95% CI 1·05–4·32) for finger sucking and 0·29 (95% CI 0·11–0·78) for hand washing with soap before meals. The attributable fractions for the first four risk factors were 6·4%, 20·9%, 57·2% and 27·5%, respectively, while the population prevented fraction for hand washing with soap before meals was 18·7%. Based on our findings, hand washing with soap should be advocated. Health education could include topics which underline the precautions which need to be taken and the advice given regarding avoiding the use of public playgrounds during epidemic periods, especially when children have been getting sick.

We studied the seasonal fluctuation of norovirus and other enteric viruses in Cameroon. Two hundred participants aged between 1 and 69 years were prospectively followed up. Each participant provided monthly faecal samples over a 12-month period. A total of 2484 samples were tested using multiplex real-time PCR assay for the detection of norovirus, rotavirus and enterovirus. The effect of weather variables and risk factors were analysed by Pearson correlation and bivariate analysis. Overall, enterovirus was the most commonly detected virus (21·6% of specimens), followed by norovirus (3·9%) and rotavirus (0·4%). Norovirus and enterovirus were detected throughout the year with a peak of norovirus detection at the beginning of the rainy season and a significant alternation of circulation of norovirus genogroups from one month to the next. Age <5 years and consumption of tap water were risk factors for norovirus infection. Better understanding of factors influencing transmission and seasonality may provide insights into the relationship between physical environment and risk of infection for these viruses.

We report the outcome of an 11-year programme monitoring sewage water and acute flaccid paralysis (AFP) cases as part of the World Health Organization (WHO) strategy for polio eradication in the Slovak Republic (SR). Polioviruses (PV) and non-polio enteroviruses (NPEV), prior to and after the change in polio vaccination strategy, were detected. Sewage treatment plant samples from 48 localities spread over the Western, Central and Eastern regions and clinical material from AFP cases were examined. The WHO standard procedures were followed with regard to virus isolation and identification. There were 538 commonly detected human enteroviruses (HEVs) including 213 (40%) coxsackie B viruses (CBV), 200 (37%) echoviruses and 113 (21%) Sabin-like PVs (PV1, 2, 3) including vaccine-derived poliovirus (VDPV) isolates. The percentage of PV isolates fell from 66% to 30% during 2001–2005 and thereafter fell to zero. CBV5, CBV2 and echovirus 3 were the NPEVs endemic during the study period.

Few reports exist regarding the association between onychomadesis and an enterovirus infection presenting clinically as hand, foot, and mouth disease (HFMD). In February 2009, an outbreak of HFMD occurred in a Spanish nursery school, followed by onychomadesis 36–69 days later. Twelve of 17 children with HFMD developed nail shedding; enterovirus was detected in stool samples from eight (47%) of the 17. However, in only three of the children could an enterovirus serotype coxsackievirus B1 be identified. The epidemiological results of this study confirm onychomadesis as a complication in HFMD. In future outbreaks, molecular characterization of enterovirus from appropriate clinical samples should be studied.

Hand, foot and mouth disease (HFMD) is generally a benign febrile exanthematous childhood disease caused by human enteroviruses. The route of transmission is postulated to be faeco-oral in developing areas but attributed more to respiratory droplet in developed areas. Transmission is facilitated by the prolonged environmental survival of these viruses and their greater resistance to biocides. Serious outbreaks with neurological and cardiopulmonary complications caused by human enterovirus 71 (HEV-71) seem to be commoner in the Asian Pacific region than elsewhere in the world. This geographical predilection is unexplained but could be related to the frequency of intra- and inter-typic genetic recombinations of the virus, the host populations' genetic predisposition, environmental hygiene, and standard of healthcare. Vaccine development could be hampered by the general mildness of the illness and rapid genetic evolution of the virus. Antivirals are not readily available; the role of intravenous immunoglobulin in the treatment of serious complications should be investigated. Monitoring of this disease and its epidemiology in the densely populated Asia Pacific epicentre is important for the detection of emerging epidemics due to enteroviruses.

The coxsackie B3 virus oriR is an element of viral RNA thought to promote the assembly of a ribonucleoprotein complex involved in the initiation of genome replication. The mutual orientation of its two helical domains X and Y is determined by a kissing interaction between the loops of these domains. Here, a genetic approach was worked out to identify spatial orientation-dependent recognition signals in these helices. Spatial orientation changes (due to linear and rotational shifts) were introduced by appropriate insertions/deletions of a single base pair into one or both of the domains, and phenotypic consequences caused by these mutations were studied. The insertion of a base pair into domain Y caused a defect in viral reproduction that could be suppressed by a base-pair insertion into domain X. Similarly, a defect in viral replication caused by a base-pair deletion from domain X could be suppressed by a base-pair deletion from domain Y. Thus, certain areas of the two domains should cross-talk to one another in the sense that a change of space position of one of them required an adequate reply (change of space position) from the other. Phenotypic effects of the local rotation of one or more base pairs (and of some other mutations) in either domain X or domain Y suggested that the two most distal base pairs of these domains served as orientation-dependent recognizable signals. The results were also consistent with the notion that the recognition of the distal base pair of domain Y involved a mechanism similar to the intercalation of an amino acid residue.

The internal ribosome entry segment (IRES) of picornaviruses consists of ∼450 nt of 5′-untranslated region, terminating at the 3′ end with an ∼25 nt element consisting of an absolutely conserved UUUC motif followed by a more variable pyrimidine-rich tract and G-poor spacer, and finally an AUG triplet, which is considered to be the actual ribosome entry site. Events following entry at this site differ among picornaviruses: in encephalomyocarditis virus (EMCV) virtually all ribosomes initiate translation at this site (AUG-11); in foot-and-mouth-disease virus (FMDV), one-third of the ribosomes initiate at this AUG (the Lab site), and the rest at the next AUG 84 nt downstream (Lb site); and in poliovirus (PV), the AUG at the 3′ end of the IRES (at nt 586 in PV type 1) is considered to be a silent entry site, with all ribosomes initiating translation at the next AUG downstream (nt 743). To investigate what determines this different behavior, chimeras were constructed with a crossover at the conserved UUUC motif: the body of the IRES, the sequences upstream of this UUUC motif, was derived from one species, and the downstream sequences from another. When the body of the FMDV or PV IRESes was replaced by that of EMCV, there was a marked increase in the absolute and relative frequency of initiation at the upstream AUG, the Lab site of FMDV and 586AUG of PV, respectively. In contrast, when the body of the EMCV IRES was replaced by that of PV, initiation occurred with no preference at three AUGs: the normal site (AUG-11), AUG-10 situated 8 nt upstream, and AUG-12, which is 12 nt downstream. Thus although the context of the AUG at the 3′ end of the IRES may influence initiation frequency at this site, as was shown by improving the context of 586AUG of PV, the behavior of the ribosome is also highly dependent on the nature of the upstream IRES. Delivery of the ribosome to this AUG in an initiation-competent manner is particularly efficient and accurate with the EMCV IRES.