Despite targeting by CRISPR-Cas system, antimicrobial resistance plasmids are prevalent in clinical isolates of carbapenem-resistant Klebsiella pneumoniae which represent a major public health threat. A stable co-existence of plasmids and CRISPR-Cas systems is mediated by anti-CRISPR (Acr) proteins. Here, we report that previously identified AcrIE10 encoded by a resistance plasmid combines two functions: it inhibits CRISPR immunity by directly binding Cas7* subunit through its Acr domain, and acts as an Acr-associated (Aca) protein that self-represses the transcription of Acr locus. AcrIE10 is an example of an Aca protein that utilizes N-terminal ribbon-helix-helix (RHH) domain to specifically recognize the inverted repeat (IR) region in its own promoter. Crucially, a dimerization of AcrIE10 dimers is required for the effective binding to the IR and self-repression, while stoichiometry-dependent interaction with Cas7* facilitates transition to de-repressed state. These findings elucidate molecular mechanisms by which AcrIE10 operates as a dual functionAcr-Aca protein to achieve a delicate balance between host CRISPR-Cas immunity and plasmid anti-defense.

The hypervirulent carbapenem-resistant Klebsiella pneumoniae (hv-CRKP) poses a substantial challenge to the global health care. However, the mechanism behind its evolution and transmission remain elusive. Here, four virulence plasmid types were identified from 310 hv-CRKP isolates collected nationwide during 2017-2018, based on their aerobactin (iuc locus) lineage and IncFIB replicons. Notably, pIUC1-IncFIB(K)(37) and pIUC1-IncFIB(Mar), representing two epidemic virulence plasmids in Asia and Europe, respectively, accounted for >90% of the hv-CRKP episodes. Analysis of 494 K. pneumoniae isolates (376 from 2010-2013; 118 from 2017-2018) and 2578 public K. pneumoniae genomes indicated the notable role of IncFIB(Mar) plasmids in the hv-CRKP emergence and spread. Conjugation assays showed the helper IncFIB(Mar) plasmid could efficiently transfer into a hypervirulent strain and uniquely retromobilize with pIUC1-IncFIB(K)(37) back into CRKP. Thereafter, the IncFIB(Mar) plasmid either lost rapidly or recombined with pIUC1-IncFIB(K)(37), generating the hybrid pIUC1-IncFIB(Mar) plasmid. Our findings elucidated formation, evolution, and dissemination trajectories of the two major hv-CRKP strains in different regions.

PURPOSE:To evaluate the effectiveness and safety of oral levofloxacin verse trimethoprim-sulfamethoxazole (TMP-SMX) for the treatment of macrolides-resistant pertussis in pediatric outpatients. METHODS:A prospective observational study was conducted at a pediatric pertussis outpatient clinic during the pertussis outbreak in 2024. For eligible children with PCR-confirmed pertussis, administration of either levofloxacin (8-10 mg/kg/dose, once or twice daily) or TMP-SMX (4-20 mg/kg/dose, twice daily) depended on parents' preference. Effectiveness and safety were evaluated for the 5-14 days duration of levofloxacin and TMP-SMX treatment in terms of alleviation of cough symptoms, bacteriologic clearance of Bordetella pertussis and adverse effects. RESULTS:Among 193 enrolled pertussis cases, eighty-four (43.53 %) received levofloxacin and 109 (56.48 %) received TMP-SMX. After completing treatment, paroxysmal cough resolved or improved in 96.43 % of levofloxacin group and 94.50 % (103/109) of TMP-SMX group (p = 0.554). Nocturnal cough resolved or improved in 98.81 % of levofloxacin group and in 98.17 % of TMP-SMX group (p = 0.057). There was no significant difference in bacteriologic clearance rate between levofloxacin group and TMP-SMX group determined by PCR (92.00 % vs 87.06 %, p = 0.378) and culture (100 % vs 100 %, p > 0.378). Symptom resolution rate did not differ significantly among patients treated for 5 or 7 days with either levofloxacin or TMP-SMX. Adverse events were reported in 9.2 % of TMP-SMX-treated patients and 2.4 % of levofloxacin-treated patients (p < 0.05). Drug rash was reported in nine (8.26 %) TMP-SMX-treated patients. CONCLUSIONS:Oral levofloxacin showed a comparable clinical effectiveness and a favorable safety profile to TMP-SMX for the treatment of non-severe pertussis with a 5-7 days course in children.

OBJECTIVE:This study aimed to investigate the virulence characteristics of Klebsiella pneumoniae (KP) strains isolated from children to analyze the genetic relatedness between pediatric and local adult CRKP isolates and to identify clinical risk factors associated with high-risk strains. METHODS:KP strains and corresponding clinical data were collected at a tertiary provincial children's hospital in Henan province from January 2021 to May 2023. The molecular and clinical characteristics of pediatric carbapenem-resistant KP (CRKP) strains were analyzed. Genomic data from local adult isolates were integrated, and the virulence profiles of pediatric and adult isolates were compared. Clinical risk factors for isolating high-risk strains were initially screened via LASSO regression and then evaluated via multivariate binomial regression. RESULTS:Among the 205 collected KP isolates, 87 (42.4%) were CRKP, and 118 (57.6%) were carbapenem-sensitive KP (CSKP). The predominant carbapenem resistance gene was blaKPC-2 (89.7%), followed by blaNDM-1 (5.7%) and blaIMP-4 (4.6%). Ten sequence types (STs) were identified among the CRKP isolates, with ST11-KL47-KPC2 (52.9%) being the predominant genotype. Screening for virulence genes revealed that 55 (63.2%) CRKP isolates carried both the hypervirulence-associated genes iuc and rmpA2. Single-nucleotide polymorphism (SNP) analysis revealed that 34 of these strains had fewer than 10 SNPs. Phylogenetic and population genetic analyses revealed close genomic relatedness between pediatric and adult CRKP strains. Young age and exposure to invasive procedures were identified as independent risk factors for the isolation of iuc+rmpA2+ CRKP. CONCLUSIONS:The ST11-KL47-KPC2 genotype was the predominant CRKP isolate in pediatric patients. The close genomic relatedness between pediatric and adult CRKP isolates suggests a common ancestor that has disseminated across populations. The high prevalence and clonal transmission of pediatric iuc+rmpA2+ CRKP strains warrant heightened clinical vigilance.

Vaccine hesitancy is a common issue for children with immune thrombocytopenia (ITP) in China. The objective of this paper is to assess the immunization statuses of children with ITP, analyze the possible relationship between immunization and thrombocytopenia, and evaluate the safety of immunization after ITP remission. We included 186 children with an ITP history and followed up with them for two years after receiving re-immunization recommendations. The participants had an overall age-appropriate vaccine coverage of 57.9%. Vaccine-associated thrombocytopenia occurred in 99 (53.2%, 95% CI = 46.06–60.26) children ranging from 0 to 34 days following immunization, with 14 vaccines involved. One hundred and fifty-four (82.3%, 95% CI = 76.72–87.54) children were advised to restart immunization, whereas 32 (17.2%, 95% CI = 12.46–23.28) were advised to postpone partial or full vaccination. Following the follow-up, 150 (80.6%, 95% CI = 74.37–85.68) children completed the catch-up immunization, whereas 27 (14.5%, 95% CI = 10.17–20.30) partially completed it. Four patients with thrombocytopenia relapsed following the re-immunization. Incomplete catch-up immunization was related to the factors of chronic thrombocytopenia, vaccine-associated thrombocytopenia, and the relapse of ITP following re-immunization. ITP may occur after immunization with vaccines other than measles-containing vaccines. Re-immunization in children with ITP generally does not result in a relapse, regardless of whether the previous thrombocytopenia was vaccine-associated.

Objectives: Klebsiella pneumoniae ( K. pneumoniae ) is one of the most common bacteria in the hospital-acquired central nervous system (CNS) infections. Central nervous system infections caused by carbapenem-resistant K. pneumoniae (CRKP) are associated with significant mortality rates and high hospital costs due to limited antibiotic treatment options. This retrospective study aimed to evaluate the clinical efficacy of ceftazidime-avibactam (CZA) for the treatment of CNS infections caused by CRKP.Methods: Twenty-one patients with hospital-acquired CNS infections caused by CRKP who received treatment with CZA for >= 72 hours were enrolled. The primary outcome was to assess the clinical and microbiology efficacy of CZA for the treatment of CNS infections caused by CRKP.Results: A high burden of comorbidity was discovered in 20 of 21 patients (95.2%). Most patients had a history of craniocerebral surgery and 17 (81.0%) of the patients were in the intensive care unit with a median APACHE II score of 16 (IQR 9-20) and SOFA score of 6 (IQR 3-7). Eighteen cases were treated by CZA-based combination therapies, while the remaining three cases were treated with CZA alone. At the end of the treatment, the overall clinical efficacy was 76.2% (16 of 21) with a bacterial clearance rate of 81.0% (17 of 21) and all-cause mortality of 23.8% (five of 21).Conclusion: This study showed that CZA-based combination therapy is an effective treatment option for CNS infections caused by CRKP.(c) 2023 Elsevier Ltd and International Society of Antimicrobial Chemotherapy. All rights reserved.

In recent years, the detection rate of carbapenem-resistant K. pneumoniae has increased and represents a major threat to clinical anti-infective therapy. Compared with KPC-type carbapenemases and NDM-type metallo-β-lactamases, OXA-48 family carbapenemases are another important resistance mechanism mediating bacterial resistance to carbapenems.

Sequence type (ST) 15 has become an emerging clone of carbapenem-resistant Klebsiella pneumoniae in which type I-E* CRISPR-Cas usually exists, indicating that the CRISPR-Cas system may not be able to block the transfer of bla KPC plasmids. The purpose of this study was to explore the mechanisms underlying dissemination of bla KPC plasmids in K. pneumoniae ST15.

BACKGROUND:Parents and healthcare providers usually defer or avoid immunization for children with neurological conditions. This study was conducted to investigate the common issues of immunization among these special children and the impact of specialists' recommendation on improving immunization practice. METHOD:We included 2,221 children with underlying neurological conditions seeking vaccination consultation at the first Immunization Advisory Clinic in China during 2017-2019. The primary neurological conditions and immunization status were analyzed. All parents were informed to self-report the adverse events following catch-up immunization. For specially concerned children with hereditary disorders, immune-related encephalopathy and epilepsy, we conducted the active follow-up to monitor the compliance with recommendation and the adverse events. RESULT:All counselling children were assessed as not having any contraindication of immunization. A total of 2,019 (90.9%) children with underlying neurological conditions had delayed immunization and 99 (4.5%) had non-immunization. The coverage rate of age-appropriate vaccines was 56.1%. The most concerned vaccines were diphtheria, tetanus and acellular pertussis combined vaccine, diphtheria and tetanus combined vaccine, meningococcal polysaccharide vaccine and Japanese encephalitis vaccine. Resuming immunization was recommended for the 2,048 (92.2%) children. Most of counselling children complied with the specialists' recommendation. Neither progress nor flaring of the neurological medical conditions was reported from parents. CONCLUSION:Vaccine hesitancy was a common issue for Chinese children with all kinds of neurological conditions. Specialized consultation on immunization is helpful to build vaccine confidence for the special children. Immunization for children with underlying neurological conditions is generally safe.

OBJECTIVES:Enterococcus faecium is one of the important pathogens causing nosocomial infection, which can be resistant to fosfomycin by obtaining the plasmid-encoded fosfomycin resistance genes, and the mutation of MurA protein encoded by chromosome is a newly discovered fosfomycin resistance mechanism in recent years. METHODS:In this study, we found a fosfomycin-resistant clinical isolate of E. faecium Efm_1415 with fosfomycin MIC of 512 mg/L, carrying Asp50Glu mutant of MurA protein, which was never reported before. To study the role and mechanism of this mutant protein in fosfomycin resistance, we used gene cloning, protein expression, and purification, steady-state kinetic, fosfomycin inhibition assay, and next-generation sequencing (NGS) to investigate the functions, characters, and enzymatic kinetic properties of MurA protein. RESULTS:The results revealed that the Asp50Glu MurA can mediate a 4-fold increase in the fosfomycin MIC of the host bacteria. Compared with the wild-type MurA, the affinity of the Asp50Glu MurA to the substrates was increased, and the enzyme activity cannot be inhibited by the concentration of fosfomycin less than 100 mg/L. CONCLUSIONS:The research on the mutant MurA had gained a new understanding of the fosfomycin resistance mechanisms and helped to find new antibiotics with MurA enzyme as the target of action.

Background: To understand the regional epidemiology and clinical characteristics of adenovirus pneumonia in hospitalized children during the 2019 outbreak of respiratory adenoviruses in China. Methods: We analyzed the epidemiologic trend of adenovirus in children hospitalized for acute lower respiratory tract infections in Xiamen in 2019. Adenovirus was identified using direct fluorescent antibody detection. During the peak seasons of adenovirus epidemic, 170 adenovirus-positive specimens were obtained for molecular typing, and the clinical data were collected. Results: Among the 9890 children hospitalized for acute lower respiratory tract infection, 609 (6.2%) were tested positive for adenovirus. The detection rate of adenovirus was significantly higher in boys than in grils (9.5% vs. 4.6%, P < 0.05). Adenovirus activity increased markedly between April and August with the prevalence of 7.3%–12.4%. During the outbreak season, type 7 accounted for 70.6%, followed by type 3 (28.8%) and type 4 (0.6%). Of the 155 cases of adenovirus pneumonia, the median age was 3.0 years (range: 4 month to 9 years), 153 (98.7%) had fever with a mean fever duration of 9.04 ± 5.52 days, 28 (16.5%) had wheezing, 93 (60%) showed segmental or lobar consolidation with atelectasis and 13 (8.4%) showed pleural effusion. Forty-six (29.6%) cases developed severe pneumonia, 7 (4.1%) required mechanical ventilation and 2 (1.2%) died. Younger age, longer duration of fever and higher fever spike were more frequently seen in severe cases ( P < 0.05). Twenty-five (16.2%) had C-reactive protein ≥ 40 mg/L, and 91 (58.7%) had procalcitonin ≥ 0.25 mg/L. Conclusions: Adenovirus types 7 and 3 caused the outbreak of adenovirus pneumonia in community children during late spring to summer in 2019 in Xiamen. The majority of adenovirus pneumonia resembles bacterial pneumonia. The incidence of severe pneumonia was high when type 7 predominantly prevailed. Adenovirus type 7 was more common in severe cases than in nonsevere cases.

Diarrhoea remains a major cause of childhood morbidity and mortality worldwide. This study aimed to monitor the aetiology of acute diarrhoea in children in Shanghai. Paediatric outpatients with acute diarrhoea were enrolled in the study from Jan 2015 to Dec 2018. Faecal samples were collected for testing. Enteric bacteria were identified and typed by culture and serotyping, respectively. Enteric viruses were identified by real-time PCR. Enteric pathogens were identified in 1572 (58.4%) of the 2692 enrolled children with acute diarrhoea. Viruses were detected more frequently than bacteria (41.3% versus 25.0%). Nontyphoidal Salmonella spp. (NTS) was the most common (10.3%) bacteria isolated, followed by enteropathogenic Escherichia coli (EPEC) (6.5%), enteroaggregative Escherichia coli (EAEC) (6.2%), Campylobacter spp. (3.6%), enterotoxigenic Escherichia coli (ETEC) (1.1%), Shigella spp. (0.2%), and enterohemorrhagic Escherichia coli (EHEC) (0.1%). Rotavirus was the most common (16.0%) virus detected, followed by norovirus (15.5%), adenovirus (7.2%), sapovirus (3.0%) and astrovirus (2.7%). Rotavirus, norovirus and NTS were the major pathogens responsible for diarrhoea in Shanghainese children. Improving uptake of the rotavirus vaccine and strengthening foodborne-pathogen prevention will aid in reducing the burden of diarrhoeal disease in children in Shanghai.

由于VR影像的空间特殊性,本研究通过设计空间视觉引导,解决观看空间中信息冗余的问题,帮助弥补VR影像剪辑点不宜过多、可用运动较少的弱点.通过分析VR影像的特点及其视觉引导特性,结合心理学中的空间工作记忆和视觉搜索的理论,开展VR影像中的空间视觉引导设计.VR影像的创作可以通过增加留白、设置目标关联以及控制场景元素辨识度等方式实现有效的引导,从而调动观者建立视觉目标与心理预期目标之间的关联,进而达到营造氛围,推动叙事的目的.VR影像的空间视觉引导设计优化了观众的视觉搜索效率,增强了观众接受信息的速度,提升了VR影像的创作空间.

Background: Antimicrobial resistance is a significant clinical problem in pediatric practice in China. Surveillance of antibiotic use is one of the cornerstones to assess the quality of antibiotic use and plan and assess the impact of antibiotic stewardship interventions. Methods: We carried out quarterly point prevalence surveys referring to WHO Methodology of Point Prevalence Survey in 16 Chinese general and children’s hospitals in 2019 to assess antibiotic use in pediatric inpatients based on the WHO AWaRe metrics and to detect potential problem areas. Data were retrieved via the hospital information systems on the second Monday of March, June, September and December. Antibiotic prescribing patterns were analyzed across and within diagnostic conditions and ward types according to WHO AWaRe metrics and Anatomical Therapeutic Chemical (ATC) Classification. Results: A total of 22,327 hospitalized children were sampled, of which 14,757 (66.1%) were prescribed ≥1 antibiotic. Among the 3,936 sampled neonates (≤1 month), 59.2% ( n = 2,331) were prescribed ≥1 antibiotic. A high percentage of combination antibiotic therapy was observed in PICUs (78.5%), pediatric medical wards (68.1%) and surgical wards (65.2%). For hospitalized children prescribed ≥1 antibiotic, the most common diagnosis on admission were lower respiratory tract infections (43.2%, n = 6,379). WHO Watch group antibiotics accounted for 70.4% of prescriptions ( n = 12,915). The most prescribed antibiotic ATC classes were third-generation cephalosporins (41.9%, n = 7,679), followed by penicillins/β-lactamase inhibitors (16.1%, n = 2,962), macrolides (12.1%, n = 2,214) and carbapenems (7.7%, n = 1,331). Conclusion: Based on these data, overuse of broad-spectrum Watch group antibiotics is common in Chinese pediatric inpatients. Specific interventions in the context of the national antimicrobial stewardship framework should aim to reduce the use of Watch antibiotics and routine surveillance of antibiotic use using WHO AWaRe metrics should be implemented.

Serogroup Y Neisseria meningitidis (NmY) is rare in China, and only serogroup A and C meningococcal polysaccharide vaccines (MPVs) are included in the national vaccination schedule. We describe a case of fulminant meningococcemia caused by NmY, which occurred in a pediatric patient (2 years old) for the first time in China, confirmed by culture. Although the boy was treated in time, the dry gangrene in his toes and fingers left him with severe sequelae. An NmY isolate was cultured from the blood of the patient, and showed decreased susceptibility to penicillin (minimum inhibitory concentration of 0.125 lg/ml), with sequence type (ST) 1655 assigned to clonal complex (cc) 23. Genomic analysis showed it was clustered with isolates from Italy, UK, Finland, and South Africa, sharing designation of Y:P1.5-1,10-1:F4-1:ST-1655(cc23). The emergence of NmY invasive meningococcal disease cases challenges local immunization strategy and warrants wider usage of MPV-ACYW if there is sustained circulation of NmY. (C) 2021 Elsevier Ltd. All rights reserved.

Background: Non-polio enrerovirus causes a wide spectrum of neurologic syndromes. The epidemiological and clinical profiles of non-polio enrerovirus-associated central nervous system infections vary by regions and over year. Objectives: This study aimed to understand the prevalence, serotypes and clinical characteristics of enterovirusassociated aseptic meningitis, encephalitis and meningo-encephalitis in children in Shanghai during 2016-2018. Methods: We collected the clinical data and the cerebrospinal fluid specimens from the pediatric patients with aseptic meningitis, encephalitis and meningo-encephalitis during 2016-2018. The nested RT-PCR and sequencing were performed to identify enterovirus and serotypes. Results: A total of 424 patients were included in this study and their non-duplicated cerebrospinal fluid specimens were collected during the acute stage of illness. Based on PCR assay, enterovirus was detected in 272 (64.15 %) patients, of whom, the ratio of male to female subjects was 1.99, and the mean age was 5.71 +/- 3.55 years (range: 0.03-16 years). There were 17 serotypes identified. Echovirus 30 (24.63 %), Coxsackievirus A10 (20.96 %), Coxsackievirus A6 (18.01 %) accounted for 63.6 %, followed by Coxsackievirus B5 (7.72 %), Echovirus 6 (5.88 %), and other serotypes (22.8 %). Of the 10 (3.68 %) critically severe patients, all had refractory seizure, 8 required mechanical ventilation, 7 survivors had recurrent attacks of epilepsy and 3 abandoned treatment; Coxsackievirus A10, Echovirus 9, Coxsackievirus A2, Coxsackievirus A6 and Echovirus 6 were identified. Conclusions: Non-polio enterovirus is the major pathogen causing aseptic meningitis, encephalitis and meningoencephalitis in Chinese children and can cause life-threatening encephalitis and severe sequelae.

Virtual reality technology has three basic characteristics: immersion, interaction and imagination. When it combines with film art, it gives a new vitality to the film, allowing the audience to gain immersed audio-visual experience, and let them have more interactive links with the film. However, in the context of film, narrative and interaction are contradictory. How to integrate interaction into film narrative is the focus of this paper. First of all, the paper analyzes the audience’s psychological motivation while they are watching films to explore when and how do they want to interact, then proposes a new concept “perceptual interaction” to define the interaction form of VR films, and summarizes the features of “perceptual interaction”, including deep immersion and “suitable to film conditions”. Though great differences are in the design of interactive forms between different categories of films, “perceptual interaction” has a set of interacting mechanisms at the emotional level, so the interaction mode of “attention - cognition - awaken - interaction - feedback” is proposed, which provides a reference for interaction design of VR films.

We first described the 2019 novel coronavirus infection in 10 children occurring in areas other than Wuhan. The coronavirus diseases in children are usually mild and epidemiological exposure is a key clue to recognize pediatric case. Prolonged virus shedding is observed in respiratory tract and feces at the convalescent stage.

To understand the epidemiological and clinical features of the symptomatic and asymptomatic pediatric cases of COVID-19, we carried out a prospective study in Shanghai during the period of January 19 to April 30, 2020. A total of 49 children (mean age 11.5 ± 5.12 years) confirmed with SARS-CoV-2 infection were enrolled in the study, including 11 (22.4%) domestic cases and 38 (77.6%) imported cases. Nine (81.8%) local cases and 12 (31.6%) imported cases had a definitive epidemiological exposure. Twenty-eight (57.1%) were symptomatic and 21 (42.9%) were asymptomatic. Neither asymptomatic nor symptomatic cases progressed to severe diseases. The mean duration of viral shedding for SARS-CoV-2 in upper respiratory tract was 14.1 ± 6.4 days in asymptomatic cases and 14.8 ± 8.4 days in symptomatic cases ( P > 0.05). Forty-five (91.8%) cases had viral RNA detected in stool. The mean duration of viral shedding in stool was 28.1 ± 13.3 days in asymptomatic cases and 30.8 ± 18.6 days in symptomatic participants ( P > 0.05). Children < 7 years shed viral RNA in stool for a longer duration than school-aged children ( P < 0.05). Forty-three (87.8%) cases had seropositivity for antibodies against SARS-CoV-2 within 1–3 weeks after confirmation with infection. In conclusion, asymptomatic SARS-CoV-2 infection may be common in children in the community during the COVID-19 pandemic wave. Asymptomatic cases shed viral RNA in a similar pattern as symptomatic cases do. It is of particular concern that asymptomatic individuals are potentially seed transmission of SARS-CoV-2 and pose a challenge to disease control.