Serotype distribution and antimicrobial resistance of pediatric Streptococcus pneumoniae isolated from inpatients and outpatients at Beijing Children's Hospital.

BACKGROUND: Understanding the epidemiology of Streptococcus pneumoniae (S. pneumoniae) isolates is important for pneumonia treatment and prevention. This research aimed to explore the epidemiological characteristics of S. pneumoniae isolated from pediatric inpatients and outpatients during the same period. METHODS: S. pneumoniae were isolated from unsterile samples of inpatients and outpatients younger than five years old between March 2013 and February 2014. The serotypes were determined using diagnostic pneumococcal antisera. The resistance of each strain to 13 antibiotics was tested using either the E-test or the disc diffusion method. The Sequence Types (STs) were analyzed via Multilocus Sequence Typing (MLST). RESULTS: The dominant serotypes obtained from inpatients were 19F (32.9 %), 19A (20.7 %), 23F (10.7 %), 6A (10.0 %), and 14 (8.6 %), while those from outpatients were 19F (13.6 %), 23F (12.9 %), 6A (10.0 %), 6B (10.0 %), and 19A (7.9 %). The coverage rates of 13-valent Pneumococcal Conjugate Vaccine (PCV) formulations were high in both groups. The nonsusceptibility to penicillin, cefuroxime, imipenem, erythromycin, and trimethoprim-sulfamethoxazole among the inpatient isolates was 7.1 %, 92.8 %, 65.7 %, 100 %, and 85.0 %, respectively, while that among the outpatient isolates was 0.7 %, 50.0 %, 38.6 %, 96.4 %, and 65.7 %, respectively. There were 45 and 81 STs detected from the pneumococci isolated from inpatients and outpatients, respectively. CC271 was common among both inpatients and outpatients (43.6 % and 14.3 %). CONCLUSIONS: Pneumococcal vaccine-related serotypes are prevalent among both inpatients and outpatients, especially among inpatients, who exhibit more severe antibiotic resistance. Therefore, universal immunization with PCV13 would decrease the hospitalization rate due to S. pneumoniae and the antibiotic resistance rate of S. pneumoniae.

[Research progress on the mechanism of -lactam resistance in group A Streptococci in vivo]. / Aæ—é“¾çƒèŒä½“å† è€å—-å† é °èƒºç±»è¯ç‰©çš„æœºåˆ¶ç ”ç©¶è¿›å±•.

-lactams, including penicillin, have been used for over 80 years in the treatment of group A Streptococcus (GAS) infections. Although -lactam-resistant GAS strains have not been identified in vitro tests, clinical treatment failures have been reported since the 1950s. The mechanism underlying the clinical failure of -lactam treatment in GAS infections remains unclear. Previous research has suggested that -lactam resistance in GAS in vivo is associated with reduced drug susceptibility of strains, bacterial inoculation effects, biofilm formation, the effect of coexisting bacteria, bacterial persistence, and bacterial internalization into host cells. This article reviews the main reports on -lactam treatment failure in GAS infections and analyzes the possible mechanisms of -lactam resistance in vivo. The findings aim to contribute to future research and clinical approaches in the field.

[Recent research on the epidemiology and preventive strategies of neonatal group B Streptococcus infection in the latest decade]. / 新生儿Bæ—é“¾çƒèŒæ„ŸæŸ“æµè¡Œç— å­¦å’Œé¢„é˜²ç­–ç•¥è¿‘åå¹´æ¥çš„ç ”ç©¶è¿›å±•.

Currently, the main strategy for preventing neonatal group B Streptococcus (GBS) infection is prenatal screening combined with intrapartum antibiotic prophylaxis, which has effectively reduced the incidence of neonatal GBS early-onset disease. However, the burden of GBS infection is still significant. The intrapartum antibiotic prophylaxis strategy has limitations such as inducing antibiotic resistance and inability to effectively prevent GBS late-onset disease. It is crucial to develop and evaluate other prevention strategies, while paying close attention to assessing penicillin allergy in pregnant women and how to prevent GBS infection in neonates with negative maternal GBS screening. In recent years, there has been some progress in GBS vaccines and related immunological research, and the use of specific vaccines is expected to significantly reduce GBS infection in neonates.

[Paying attention to the epidemic of group A Streptococcus infections in multiple European and American countries]. / å ³æ³¨æ¬§ç¾Žå¤šå›½Aæ—é“¾çƒèŒæ„ŸæŸ“ç–«æƒ .

At the end of 2022, the World Health Organization reported an increase in group A Streptococcus (GAS) infections, such as scarlet fever, in multiple countries. The outbreak primarily affected children under 10 years old, and the number of deaths was higher than anticipated, causing international concern. This paper reviews the current state of the GAS disease outbreak, its causes, and response measures. The authors aim to draw attention from clinical workers in China and increase their awareness and vigilance regarding this epidemic. Healthcare workers should be aware of the potential epidemiological changes in infectious diseases that may arise after the optimization of control measures for coronavirus disease 2019 to ensure children's health.

The dynamic change of serotype distribution and antimicrobial resistance of pneumococcal isolates since PCV13 administration and COVID-19 control in Urumqi, China.

Objective: This study aims to analyze the serotype distribution and drug resistance of Streptococcus pneumoniae isolated from children aged 8 days to 7 years in Urumqi, China, between 2014 to 2021, during which PCV13 was introduced in the private sector's immunization program and COVID-19 control was administrated in the last 2 years. Methods: Serotypes of S. pneumoniae isolates were determined by Quellung reaction, and their susceptibility against 14 antimicrobials were tested. According to the start year of PCV13 administration (2017) and COVID-19 control (2020), the study period was divided into three stages: 2014-2015, 2018-2019, and 2020-2021. Results: A total of 317 isolates were involved in this study. The most common serotypes were type 19F (34.4%), followed by 19A (15.8%), 23F (11.7%), 6B (11.4%), and 6A(5.0%). The coverage rate of both PCV13 and PCV15 was 83.0%. The coverage of PCV20 was a little higher at 85.2%. The resistance rate against penicillin was 28.6% according to the breakpoints of oral penicillin, which would reach up to 91.8% based on the breakpoints of parenteral penicillin for meningitis. The resistance rates to erythromycin, clindamycin, tetracycline, and sulfamethoxazole-trimethoprim were 95.9%, 90.2%, 88.9%, and 78.8%, respectively. The PCV13 isolate was more resistant to penicillin than the non-PCV13 ones. There was not any significant change found in the serotype distribution since the PCV13 introduction and the COVID-19 control. The resistance rate against oral penicillin slightly elevated to 34.5% in 2018-2019 from 30.7% in 2014-2015 and then decreased significantly to 18.1% in 2020-2021 (χ 2 = 7.716, P < 0.05), while the resistance rate to ceftriaxone (non-meningitis) continuously declined from 16.0% in 2014-2015 to 1.4% in 2018-2019 and 0% in 2020-2021 (Fisher = 24.463, P < 0.01). Conclusion: The common serotypes of S. pneumoniae isolated from children in Urumqi were types 19F, 19A, 23F, 6B, and 6A, which we found to have no marked change since the PCV13 introduction and the COVID-19 control However, the resistance rate to oral penicillin and ceftriaxone significantly declined in the COVID-19 control stage.

[Interpretation of "Clinical Considerations for Monkeypox in Children and Adolescents" released by the US Centers for Disease Control and Prevention]. / ç¾Žå›½ç–¾ç— é¢„é˜²å’ŒæŽ§åˆ¶ä¸­å¿ƒå‘å¸ƒçš„ã€Šå„¿ç«¥å’Œé’å°‘å¹´çŒ´ç—˜çš„ä¸´åºŠæ³¨æ„äº‹é¡¹ã€‹è§£è¯».

In order to cope with monkeypox in children and adolescents, the US Centers for Disease Control and Prevention released "Clinical Considerations for Monkeypox in Children and Adolescents", which is specially written for pediatric health workers serving children and adolescents under the age of 18 years to standardize the clinical management of children and adolescents with exposure to monkeypox (human monkeypox or animal monkeypox) or with suspected or confirmed monkeypox. This document highlights the characteristics of children and adolescents and gives some valuable suggestions to the special issues in pediatric clinical practice, and it is worth studying by pediatric health workers who are preparing for a possible epidemic of monkeypox.

[Clinical features and epidemiological significance of pertussis in infants]. / å©´å„¿ç™¾æ—¥å’³çš„æµè¡Œç— å­¦æ„ä¹‰åŠå ¶ä¸´åºŠç‰¹ç‚¹.

Infantile pertussis is clear evidence for the persistent transmission of pertussis in communities. Infants are the most vulnerable population for pertussis infection and are also important nodes in pertussis transmission networks in communities, and therefore, the prevention of infantile pertussis is the core of prevention and control measures against pertussis including vaccine immunization. Although the cases of pertussis reported in China are mainly infants with pertussis, the actual number of infants with pertussis might be higher than the reported number. It is necessary in clinical practice to improve the awareness of this disease and promote related laboratory tests. On the basis of emphasizing the identification of pertussis in infants, timely diagnosis and treatment, follow-up visits, and standard management of the close contacts of infants with pertussis should be performed to reduce and block the community transmission of pertussis.

[Diagnosis and treatment of human monkeypox]. / 人感染猴痘的诊断和治疗.

The guideline for the diagnosis and treatment of monkeypox (2022 edition) issued by National Health Commission of the People's Republic of China introduces the key knowledge of the diagnosis and treatment of human monkeypox (HMPX) and does not systematically introduce the sampling methods and requirements of specimens for HMPX etiology testing and the discrepancy in diagnostic criteria between China and overseas. However, the doctors who are not engaged in dermatology lack understanding of the sampling methods and requirements of specimens for laboratory diagnosis of HMPX, and there are few relevant references available. This article collects the information on the diagnosis and treatment of HMPX, so as to provide a reference for learning, understanding, and application of this guideline.

Clinical characteristics and epidemiological significance of coronavirus disease 2019 in children and adolescents. / 儿童和青少年2019å† çŠ¶ç— æ¯’ç— çš„ä¸´åºŠè¡¨çŽ°åŠæµè¡Œç— å­¦æ„ä¹‰.

The epidemic of coronavirus disease 2019 (COVID-19) started in late December 2019, and spread rapidly throughout the world. In March 2020, the World Health Organization (WHO) declared global epidemic of COVID-19. According to the American Academy of Pediatrics, nearly 13 million children have been diagnosed with COVID-19 since the outbreak. In general, children and teens have milder symptoms and fewer deaths from COVID-19 than adults. Understanding the symptoms, infectivity, and transmission patterns of COVID-19 in children and adolescents is of great significance for timely identifying suspected patients and developing effective control measures. Considering that some children will not be vaccinated for quite some time in the future, it is more important to improve the understanding of the clinical and epidemiological significance of COVID-19 in children and adolescents. This article summarizes the current understanding of the clinical manifestations and epidemiological significance of COVID-19 in children and adolescents to provide a reference for clinical diagnosis and treatment and the formulation of epidemic prevention and control strategies in children's gathering institutions such as kindergartens and schools.

[Learning from the past: the history of human monkeypox and the atypical multi-country outbreak in 2022]. / çŸ¥å¾€é‰´ä»Šï¼šäººæ„ŸæŸ“çŒ´ç—˜å²åŠå ¶éžåŒå¯»å¸¸çš„2022å¹´å¤šå›½æš´å‘ç–«æƒ .

In 2022, the outbreak of human monkeypox (HMPX) occurred in many non-endemic countries. World Health Organization (WHO) assesses that this outbreak is "atypical". The history of monkeypox and HMPX must be reviewed to clearly recognize the "typical" outbreaks to fully understand this comment. Therefore, this paper reviews the epidemiological history of monkeypox, especially HMPX, and discusses and analyzes the atypical manifestations and the possible causes of the present outbreak based on the recent views of WHO, other organizations/institutions, and experts. The text describes the thought-provoking history of the interaction between the monkeypox virus and the human being in the past 64 years, and provides various information and views on the outbreak of HMPX, which is helpful to understand risk assessment and the potential impact of this outbreak on clinical and public health in future.

[The investigation on the acute, severe hepatitis of unknown origin in children]. / å„¿ç«¥ä¸æ˜ŽåŽŸå› æ€¥æ€§ä¸¥é‡è‚ç‚Žç— ä¾‹è°ƒæŸ¥è¿›å±•.

In April 2022, the United Kingdom notified the World Health Organization (WHO) of an unexpected increase of acute hepatitis of unknown origin in children. Subsequent investigations have found more than 400 cases in more than 20 countries and regions around the world. Although the potential role of adenovirus type 41 in the pathogenesis of these cases is one hypothesis, but it is probably not the only pathogenic factor, and other infectious and non-infectious causes cannot be completely ruled out. For hepatitis caused by non-hepatitis A, B, C, D and E viruses, there is a lack of systematic monitoring and research, and many unknowns still exist. According to the current etiology speculation and epidemiological characteristics of adenovirus in China, cases of acute hepatitis with unknown origin may be found in China in the future. There is also a risk of imported cases. This article systematically sorts out the reports and studies on child acute hepatitis of unknown origin, hoping to attract the attention of pediatric clinicians in China, raise awareness and vigilance, and calmly prepare for possible abnormal situations.

Clinical characteristics, antimicrobial resistance, and risk factors for mortality in paediatric invasive pneumococcal disease in Beijing, 2012-2017.

BACKGROUND: To analyse clinical characteristics, antibiotic susceptibility, and risk factors for mortality in paediatric invasive pneumococcal disease (IPD) in Beijing. METHODS: Paediatric IPD patients in our hospital were retrospectively collected from 2012 to 2017. Clinical manifestations, laboratory tests, antimicrobial susceptibility and serotype of isolates, and risk factors for mortality of IPD were analysed. RESULTS: Overall, 186 IPD cases were enrolled. The major manifestations were meningitis (76), pneumonia with bacteraemia (60), bacteraemia without focus (21), and pneumonia with empyaema (22). Of 72 cases with underlying diseases, leukaemia (18.0%), congenital heart disease (15.3%), primary immunodeficiency disease (12.5%), nephrotic syndrome (12.5%), and cerebrospinal fluid leakage (12.5%) were most common. In total 96.9% of isolates would have been covered by the pneumococcal conjugate vaccine (PCV13), including 19F (32.8%), 19A (23.4%), 4 (17.2%), and 23F (9.4%). Nonsusceptibility rates of penicillin, cefotaxime, and cefepime among nonmeningitis patients increased between 2012 and 2017; The mortality rate was 21.5%. Meningitis, respiratory failure, multiple organ failure, and white blood cell count < 4000 cells/µL were independent risk factors for mortality. CONCLUSION: Meningitis was the most common clinical manifestation of IPD, and was frequently associated with death. Strains in the PCV13 vaccine would cover most of the cases, and so wider use of PCV13 should be considered.

Epidemiology of non-vaccine serotypes of Streptococcus pneumoniae before and after universal administration of pneumococcal conjugate vaccines.

The universal administration of pneumococcal conjugate vaccines (PCVs) had been demonstrated as an effective way to prevent Streptococcus pneumoniae infection. However, the immunity induced by PCVs protected against the infections caused by vaccine serotypes, which were usually more frequent than non-vaccine serotypes (NVTs). The prevalence and pathogenicity of NVTs after universal vaccination have caused widespread concern. We reviewed the epidemiology of non-PCV13 S. pneumoniae before and after PCV13 introduction, and explored the potential reasons for the spread of NVTs. Emerging and spreading NVTs can be regarded as the focus for future serotype epidemiological survey and vaccine optimization.AbbreviationsIPD: invasive pneumococcal disease PCV: pneumococcal conjugate vaccines VT: vaccine serotypeNVT: non-vaccine serotype.

One cross-sectional investigation revealed that non-vaccine serotypes of Streptococcus pneumoniae could be identified more frequently in elderly Chinese people.

OBJECTIVE: To analyze the serotype distribution and drug resistance of Streptococcus pneumoniae isolated from hospitalized patients of all ages in Zhongjiang county, Sichuan province, where the young children have just begun to vaccinate the PCV13 in private sector. METHODS: Serotypes were determined for 387 isolates of S. pneumoniae by Quellung reaction. Antibiotic susceptibility was tested with the E-test or disc diffusion method. RESULTS: The most common serotypes were type 19F and confirmed for 88 isolates (22.7%), followed by 19A (15.0%), 6B (7.8%), 16F (7.8%), 23F (7.0%) and 15A (4.4%). The coverage rates of PCV13 and PPSV23 were 63.3% and 65.1%. With the increase of age, the proportion of PCV13 types decreased significantly, from 71.3% (<2 years old) to 41.9% (≥60 years old). The intermediate rate and resistance rate of the isolates to oral penicillin were 48.6% and 45.2%, respectively. The resistance rate of erythromycin was high (94.4%). The PCV13 isolates was more resistant to penicillin than the non-PCV13 ones. CONCLUSION: The PCV13 coverage rate in pediatric isolates was higher than those in adult isolates. The adults, especially the elderly, may be the reservoir of non-PCV13 types. It is necessary to investigate the serotype distribution of S. pneumoniae based on all age population to assess potential epidemics of non-vaccine serotype associated with PCVs administration.

Properties of Mucoid Serotype 3 Streptococcus pneumoniae From Children in China.

Objective: To investigate the characteristics of hosts, antimicrobial susceptibility, and molecular epidemiology of mucoid serotype 3 Streptococcus pneumoniae (S. pneumoniae) isolated from children in China. Method: S. pneumoniae isolates collected between January 2016 and December 2019 were analyzed. S. pneumoniae isolates with mucoid phenotype were selected visually, and serotype 3 isolates were confirmed by Quellung reaction. The antimicrobial susceptibility was measured by E-test. Multilocus sequence typing was used for clonal analysis. Results: Twenty (3.04%) isolates of mucoid serotype 3 S. pneumoniae were identified from 657 clinical isolates, and all of them were noninvasive strains. The mean age of the hosts was 5.69 ± 3.28 years. The isolates included: 50.0% from the dissected tonsil or adenoid tissue in children with obstructive sleep apnea-hypopnea syndrome, 45.0% from sputum or bronchial lavages in children with pneumonia, and 5.0% from vaginal secretions of one patient with vulvovaginitis. All isolates were susceptible to penicillin, cefuroxime, ceftriaxone, meropenem, vancomycin, levofloxacin, trimethoprim/sulfamethoxazole, and rifampin but resistant to erythromycin. Sequence type (ST)505 and its clonal complex (CC) were the main genotypes (95%). Antimicrobial susceptibility of ST180 and ST505 were compared, and the minimum inhibitory concentration (MIC) of ST505 isolates was significantly higher than that of ST180 for tetracycline, trimethoprim/sulfamethoxazole, and meropenem. Conclusions: Mucoid serotype 3 Streptococcus pneumoniae can be isolated from various body parts, among which the respiratory system is the most common. It can cause noninvasive infection in children, and it has high susceptibility to a variety of antibiotics, especially ß-lactams, but is resistant to macrolides. CC505 is the novel clonal complex found in China, which may be related to the worldwide mainstream clonal complex (CC180) but has its own biological characteristics.

Clinical and molecular characteristics of Staphylococcus aureus isolated from Chinese children: association among the agr groups and genotypes, virulence genes and disease types.

BACKGROUND: This study was aimed to investigate the clinical and molecular epidemiology of Staphylococcus aureus (S. aureus) isolated from Chinese children and determine the possible relationship among the accessory gene regulator (agr) groups and genotypes, as well as among the virulence genes and disease types. METHODS: S. aureus strains were isolated from Beijing Children's Hospital between October 2017 and October 2019. The isolates and 19 virulence genes were characterized using multi-locus sequence typing, staphylococcal protein A (spa), staphylococcal cassette chromosome mec, and agr typing. RESULTS: A total of 191 non-repetitive S. aureus clinical isolates were divided into 33 sequence types (STs), 18 clonal complexes (CCs), and 59 spa types. ST59 (39.8%), t437 (37.7%), and agr I (84.8%) were the predominant types. CC59, CC25, CC22, CC951, CC8, and CC398 belonged to agr I. CC5 and CC15 were assigned to agr II, and CC30 was characterized as agr III. CC121 was classified under agr IV. The eta, etb, and bbp genes were more prevalent in agr IV (P < 0.001 for each), while tst was more prevalent in agr group III compared to the other groups (P < 0.001). Nearly all isolates that harbored lukS/F-PV belonged to agr I (P = 0.005). However, the correlation between disease types and agr groups was not significant (P > 0.05). CONCLUSIONS: An association among the agr groups and genotypes, as well as specific toxin genes, was observed among the S. aureus strains isolated from Chinese children. However, a statistical correlation was not found among the agr groups and disease types.

[Research advances in the treatment strategies for severe pertussis in children].

At present, effective antibiotics and comprehensive symptomatic/supportive treatment as early as possible are mainly used for the treatment of severe pertussis in clinical practice. However, some children with severe pertussis have unsatisfactory response to commonly used drugs and treatment measures in the intensive care unit and thus have a high risk of death. Studies have shown that certain treatment measures given in the early stage, such as exchange transfusion, may help reduce deaths, but there is still a lack of uniform implementation norms. How to determine the treatment regimen for severe pertussis and improve treatment ability remains a difficult issue in clinical practice. This article reviews the advances in the treatment of severe pertussis, in order to provide a reference for clinical treatment and research.

One single-center cross-sectional investigation on varicella antibody level of all age groups in Chinese people.

Varicella outbreaks were mainly reported in developed regions with high vaccine coverage, but not in undeveloped areas. It is still not clear that whether the published data of varicella epidemiology could reflect the reality in China or not. In 2019, 657 subjects from People's Hospital of Chongqing Youyang County were included. Anti-varicella-zoster virus (VZV) IgG antibodies were determined by ELISA. The anti-VZV IgG levels were categorized as positive when values were ≥100 mIU/mL. Our results showed that the rates of anti-VZV IgG seropositivity (χ2 = 328.957, P < .0001) and geometric mean titers (P < .0001) were significantly influenced by age. The seropositivity declined dramatically from 84.5% in subjects ≤3 m of age, to 7.9% in subjects of >3 m-1 y (P < .0001). Then, the positivity rate increased slowly as age to 26.7% in >1-<3 y (P = .0006), and 34.5% in 3-<7 y (P = .4294). A steady rise (45.6%) in positivity was observed in subjects aged 7-<18 y. After then, the positivity began to increase robustly. A total of 87.8% of adults aged 18-<40 y had acquired VZV-specific immunity (P < .0001). The highest positivity rate was found in 40-<60 y  (98.3%) and ≥60 y (98.2%) group. In conclusion, most subjects of >3 m-<7 y age were susceptible to VZV. The proportion of subjects with natural infection-induced immunity increased with age. Nearly all subjects over 40 ages had positive anti-VZV IgG antibodies, which proved that they were infected by this virus in the past. These results suggested that VarV should be included in the national immunization program in China.