[Etiology surveillance of hand-foot-mouth disease in Henan province between 2008 and 2011].

OBJECTIVE: To understand etiological types and distribution features of hand-foot-mouth disease (HFMD) in Henan province between 2008 and 2011. METHODS: A total of 30 486 specimens of feces, rectal swabs or throat swabs from HFMD patients were collected by each Municipal CDC in Henan from 2008 to 2011. The enterovirus 71 (EV71), coxsackie virus A16 (CA16) and other enterovirus (EV) were detected by RT-PCR or real time RT-PCR. The VP1 gene of EV71 was amplified and the sequences were analyzed by bioinformatics software. A genetic evolution tree of the sequence was constructed as well. RESULTS: The positive rates of EV71, CA16 and other EV were 62.70% (11 209/17 876), 12.03% (2150/17 876), 25.27% (4517/17 876) in 17 876 laboratory diagnosed cases, respectively. The differences were statistically significant (χ(2) = 157.17, P < 0.05). The positive rates of EV71, CA16 and other EV were 63.40% (7370/11 624), 11.58% (1346/11 624) and 25.02% (2908/11 624) in male patients and 61.40% (3839/6252), 12.86% (804/6252) and 25.74% (1609/6252) in female patients, respectively. The differences were statistically significant (χ(2) = 4.06, P < 0.05). The children under 5 years old were high-risk population of HFMD, accounting to 97.67% (17 459/17 876) of the laboratory-diagnosed patients.86.92% (15 537/17 876) cases were children between 1 to 3 years old. Constituent ratio of EV71 changed seasonally during a year, there was a high infection ratio of EV71 between April and June, especially in May, the infection ratio reached 69.34% (2384/3438). The positive rates of EV71, CA16 and other EV were 82.48% (5715/6929), 1.76% (122/6929) and 15.76% (1092/6929) among the 6929 laboratory-diagnosed severe cases, respectively. The positive rates of EV71 was higher than CA16 and other EV (χ(2) = 9259.17, 6170.81, P < 0.05, respectively). There were 117 deaths because of severe HFMD, 55 (47.01%) of which were laboratory confirmed. 50 death cases were infected by EV71, and according to the genetic evolution analysis, the VP1 gene of EV71 strain was belonged to subtype C4 of gene C. CONCLUSION: The EV71 and CA16 were the main pathogens which caused HFMD in Henan province, and EV71 virus was the dominant strain, belonging to C4 subtype of gene C.

Chinese guidelines for the diagnosis and treatment of hand, foot and mouth disease (2018 edition).

BACKGROUND: Hand, foot, and mouth disease (HFMD) is a common infectious disease in childhood caused by an enterovirus (EV), and which is principally seen in children under 5 years of age. To promote diagnostic awareness and effective treatments, to further standardize and strengthen the clinical management and to reduce the mortality of HFMD, the guidelines for diagnosis and treatment have been developed. METHODS: National Health Commission of China assembled an expert committee for a revision of the guidelines. The committee included 33 members who are specialized in diagnosis and treatment of HFMD. RESULTS: Early recognition of severe cases is utmost important in diagnosis and treatment of patients with HFMD. The key to diagnosis and treatment of severe cases lies in the timely and accurate recognition of stages 2 and 3 of HFMD, in order to stop progression to stage 4. Clinicians should particularly pay attention to those EV-A71 cases in children aged less than 3 years, and those with disease duration less than 3 days. The following indicators should alert the clinician of possible deterioration and impending critical disease: (1) persistent hyperthermia; (2) involvement of nervous system; (3) worsening respiratory rate and rhythm; (4) circulatory dysfunction; (5) elevated peripheral WBC count; (6) elevated blood glucose and (7) elevated blood lactic acid. For treatment, most mild cases can be treated as outpatients. Patients should be isolated to avoid cross-infection. Intense treatment modalities should be given for those severe cases. CONCLUSION: The guidelines can provide systematic guidance on the diagnosis and management of HFMD.

[Hand-foot-mouth disease pathogen separation and EV71 VP1 gene analysis in Sanmenxia City, Henan Province, China].

The aim of this study was to understand the enterovirus types and biological features of pediatric cases of HFMD in Sanmenxia City during 2011, and compare the latter to a cohort of healthy children. Stool samples of 55 cases of HFMD and 60 healthy children were collected for the isolation and identification of enteroviruses using RNA extraction and real-time RT-PCR assays. EV71 and CA16 were identified by nucleotide sequencing using virus-specific VP1 primers; for the other enteroviruses, 012/011 and 008/013 primers were used for amplification and sequencing. The results were analysed by sequence alignment with known sequences, and the characteristics of the EV71 VP1 gene were also analyzed. The detection rates for enteroviruses in cases of HFMD and healthy children were 52.73% (29/55) and 18.33% (11/60), respectively. Among these, there were 22 cases of EV71, four cases of CA16 and three cases of other enteroviruses in the cases with HFMD. Eleven healthy children had intestinal viruses, of which nine were Coxsackie B virus strains (81.82%, 9/11). Gene sequencing of the 19 EV71 strains illustrated that they were all subgenotype C4a, but the evolutionary tree showed an obvious clustering between cases from Lingbao City and Lushi County. This study demonstrates that the EV71 subgenotype C4a and CA16 strains were the most common cause of HFMD in Sanmenxia City in 2011, and that Coxsackie B strains were prevalent in healthy children. This finding may indicate that there is a widespread source of recessive infection in the community.

Arabidopsis RPG1 is important for primexine deposition and functions redundantly with RPG2 for plant fertility at the late reproductive stage.

Arabidopsis Ruptured Pollen Grain-1 (RPG1/Sweet8) is a member of the MtN3/saliva protein family that functions as a sugar transporter. The rpg1 mutant shows defective exine pattern formation. In this study, transmission electron microscopy (TEM) observations showed that much less primexine was deposited in rpg1 tetrads. Furthermore, microspore membrane undulation was abnormal, and sporopollenin accumulation was also defective. This suggests that a reduced primexine deposition in rpg1 leads to abnormal membrane undulation that affects exine pattern formation. Chemical staining revealed thinning of the callose wall of rpg1, as well as significantly reduced expression of Callose synthase-5 (CalS5) in rpg1. The fertility of the rpg1 mutant could be partly restored at late reproductive stages, potentially complemented in part by RPG2, another member of the MtN3/saliva family, which is expressed in the anther during microsporogenesis. The double mutant, rpg1rpg2, was almost sterile and was not restored during late reproduction. These results suggest that RPG1 and RPG2 are involved in primexine deposition and therefore pollen wall pattern formation.

[Genetic characteristics of enterovirus 71 VP1 and epidemiology of hand-foot-mouth disease in Xinxiang in 2011].

The study was performed to examine the enterovirus 71(EV71) VP1 genetic feature and the epidemiology of hand-foot-mouth disease (HFMD) in Xinxiang in 2011. Real-time RT-PCR was used for the detection of Pan-enterovirus, Coxsackievirus A 16(CA16) and EV71 from stool specimens of HFMD. The VP1 region was amplified from 10 EV71 positive samples and the products were sequenced. EV71 genotypes were characterized by homology and phylogenetic tree analyses. Additionally, epidemic data of Xinxiang HFMD in 2011 was analyzed. The results revealed that 73% of the specimens from severe cases were determined as EV71 positive, which was significantly higher than CA16-positive ones (19%) (P < 0.01). Ten EV71 strains isolated in Xinxiang belonged to C4a cluster of sub-genotype C4, with 2.8% nucleotide and 0.9% amino acid sequences divergence among them. At position 170 in VP1 gene, an alanine(A) was predominant in 9 isolates, while a valine(V) residue was observed in one isolate. Compared to the representative C4a strains which were closely related to Xinxiang isolates, the amino acid variations of the pre-dominant Xinxiang strains generally occurred at position 292, threonine --> alanine (T --> A). A total of 1118 HFMD cases were reported in Xinxiang in 2011, and 92% of them were younger than 3 years old; the incidence rate peaked in April and December, suggesting that it is very necessary to strengthen HFMD prevention and control even in cold weather.

[Genomic characteristics of coxsakievirus A16 isolated in Henan Province].

To reveal the genomic sequence characteristics of coxsackievirus A16 (CoxA16) strain isolated from patients with hand-foot-mouth disease (HFMD) in Henan province. A total of 406 samples were detected by reverse-transcription polymerase chain reaction (RT-PCR) and cell-culture-based isolation of coxsackievirus A16. The whole genome of CoxA16 isolate was amplified using 10 pairs of primers, the sequences were analyzed and phylogenetic tree was generated by bioinformatics software. The full length of HN1162/HN/CHN/2010 genome was 7411bp. Compared with the other CoxA16 strains released in GenBank, the nucleotide similarities were 87.0-97.9%, 77.0%-95.4%, 80.3%-96.9%, 77.9% 96.2%, 80.5-100% in 5'UTR, P1, P2, P3, 3'UTR region, respectively; The similarities of nucleotide and amino acid sequences in VP1 region were 91.4%-96.4% and 99.3%-99.7%, respectively. Phylogenetic tree analysis showed that CoxA16 strains isolated from Henan, Shenzhen, Guangzhou and Fujian belonged to the same cluster. The newly isolated CoxA16 from Henan province belonged to subgenotype C2/B-2. These results will have great significance in monitoring CoxA16 and for prevention and control of hand-foot-mouth disease.