For a long time, macrolides have been the first choice for the antibacterial treatment for pertussis.However, in the past decade, resistance to macrolide antimicrobials has been common in clinically isolated Bordetella pertussis in China, which is in contradiction with the recommended macrolide treatment.Therefore, Trimethoprim-Sulfamethoxazole (TMP-SMZ) is suggested as the first choice for antibacterial treatment for pertussis in China, with a dosage determined according to age and body weight, lasting 14 days.If TMP-SMZ cannot be used, full-dose and full-course β-lactam antimicrobials may be used, of which the effects should be assessed carefully.The impact of other antibacterial drugs, such as quinolones and tetracyclines, on the elimination of Bordetella pertussis should also be evaluated as soon as possible to treat adult pertussis and potential cases caused by drug-resistant bacteria in future.

Objective:To determine the erythromycin resistance of Bordetella pertussis isolates and their ptxP1 and ptxP3 phenotypic composition and compare clinical manifestations of children with pertussis caused by the two types of strains. Methods:This was a cross-sectional study, the pertussis cases diagnosed using bacterial culture from January 2019 to December 2022 in Beijing Children′s Hospital and the First People′s Hospital of Wuhu were collected.Any suspected Bordetella pertussis colonies were identified by the slide agglutination test.The susceptibility of isolates to erythromycin was detected by the E-test and K-B test.The ptxP gene was amplified by polymerase chain reaction and sequenced to determine its genotype. t-test, Mann-Whitney U-test, Chi-square test and Fisher′s exact test were use to statistical analysis. Results:A total of 192 strains of Bordetella pertussis were identified, including 188 (97.9%) erythromycin-resistant strains.Among the 188 strains, 30.3%(57/188) belonged to the ptxP1 genotype and 69.7%(131/188) belonged to the ptxP3 genotype.In children aged below 1 year old, the incidence of paroxysmal cough caused by infection with the ptxP3 strain was higher than that with the ptxP1 strain (57.1% vs.29.4%, P<0.05), and children infected with the ptxP3 strain were more likely to develop apnea or asphyxia (23.8% vs.17.6%), post-tussive vomiting (44.4% vs.32.4%), whooping cough (72.0% vs.50.0%) and pneumonia or bronchitis (85.7% vs.73.5%) compared to those infected with the ptxP1 strain, but the differences were not statistically significant(all P>0.05). In children aged 1 year old and above, the white blood cell count of children infected with the ptxP1 strain was higher than that of infections with the ptxP3 strain [13.5(9.9, 24.5)×10 9/L, 10.3 (7.0, 16.4)×10 9/L, P<0.05], and children infected with the ptxP1 strain were more likely to contract other pathogen infections than those infected with the ptxP3 strain (17.4% vs.4.4%, P>0.05). Conclusions:ptxP3 erythromycin-resistant Bordetella pertussis has become the main pathogen of pertussis.Infants with pertussis caused by the ptxP3 erythromycin-resistant strain show more significant manifestations and a higher possibility of severe symptoms than those infected with the ptxP1 erythromycin-resistant strain.

Group A Streptococci(GAS)can cause multiple diseases such as pharyngotonsillitis, scarlet fever, streptococcal toxic shock syndrome(STSS), necrotizing fasciitis, and so on, making it extremely difficult to monitor all GAS infections.Developed countries such as the United States and the United Kingdom have classified invasive GAS diseases/infections(iGAS) or certain specific types, such as STSS, as notifiable diseases.China only includes scarlet fever caused by GAS infections in the legal infectious diseases.Although case reports or clinical studies of STSS and necrotizing fasciitis in China can be found, there is a lack of investigation and summary on iGAS, and there are few materials to introduce its definition and diagnostic criteria.Based on a recently diagnosed typical case, this paper intends to introduce the definition and diagnostic criteria of iGAS adopted in the United States, the United Kingdom and other developed countries, as well as the valuable early manifestations and risk factors, and the incidence of iGAS.Given the epidemiological changes in GAS infections in recent years, this paper also emphasizes the importance of paying attention to GAS infections, especially iGAS, aiming to arouse the attention of China′s clinical doctors and urge them to carry out research on this group of diseases.

It is difficult to accurately distinguish pharyngitis caused by Group A Streptococcus(GAS) from other pathogens according to the clinical presentation alone, which cannot effectively guide the rational use of antimicrobials.The pharyngeal swab culture, rapid antigen detection test, nucleic acid test, and blood test can help definitively diagnose GAS pharyngitis.However, there are differences in different guidelines on who the laboratory test methods are intended for, interpretation of laboratory test results and so on.This article summarizes and analyses the laboratory diagnostic modalities and their characteristics, as well as recommendations for GAS pharyngitis in different guidelines to provide references for the clinical diagnosis, antimicrobial treatment, and further study of GAS pharyngitis.

Pertussis is a highly contagious acute respiratory infection.Although childhood vaccination has been widely practiced, it does not result in lifelong immunity.On December 21, 2022, aiming to meet the challenge of pertussis epidemic in the world, European Centre for Disease Prevention and Control published laboratory diagnosis and molecular surveillance of Bordetella pertussis, which describes in detail the protocols for laboratory diagnosis and molecular technology for pertussis, and it is worthwhile to study and learn from healthcare professionals and technicians engaged in the field of diagnosis and treatment of pertussis disease in China.This article introduces and interprets the main contents of the document.

The disease surveillance found that non-pharmaceutical interventions (NPIs) to prevent and control corona virus disease 2019 (COVID-19) also significantly affected the epidemiology of other infectious diseases.With the withdrawal of NPIs, the World Health Organization and other organizations have notified outbreaks of different infectious diseases.Compared with the epidemiology of these diseases before the COVID-19 pandemic, the outbreaks presented a number of atypical characteristics.The health workers should know and beware of these unusual changes to adjust strategies for diagnosis and treatment in time for the people′s health.

In recent years, although great progress has been made in the etiology diagnosis of pertussis, the treatment is unsatisfactory.In particularly, the diagnosis and treatment of severe pertussis urgently need standardization.To date, no diagnostic guidelines for severe pertussis have been published.There are many differences in diagnostic terms, definitions, or diagnostic criteria for severe pertussis in published reports, and it is also difficult to evaluate the efficacy difference among therapeutic strategies for pertussis.This article aims to provide several personal opinions on the diagnosis of severe pertussis, including infant pertussis screening, risk assessment of severe illness and death, severity assessment, and diagnosis, thus highlighting the clinical concern of severe pertussis in infants.

World Health Organization (WHO) reported that a total of 559 meningitis cases and 18 deaths were reported in the southeast of Niger from November 1, 2022 to January 27, 2023.Children were the major of patients.Among the laboratory confirmed cases, 93.7%(104/111) were epidemic cerebrospinal meningitis.Since 2021, the epidemic of meningococcal disease has attacked the gay and bisexual men in Florida, USA.This paper briefly reviews the occurrence and development of the two outbreaks of epidemic cerebrospinal meningitis, as well as the causes and countermeasures.The current prevention and control measures of meningitis is discussed based on the " Defeating meningitis by 2030: Global Road Map" issued by WHO in 2021.This paper is expected to attract the attention and to improve awareness and vigilance of domestic clinical and public health workers, which would lead to strengthen the surveillance, prevention and control of meningitis.

Objective:To examine whether the mixed infection rate in pertussis infants is significantly higher than that in non-pertussis infants with respiratory tract infection, to explore the mixed infection pathogen distribution in pertussis infants, and to provide reference for clinical diagnosis and treatment.Methods:A case-control study was conducted on 118 nasopharyngeal swabs collected from infants who applied for clinical pertussis etiological testing (culture and specific nucleic acid detection of Bordetella pertussis) in Beijing Children′s Hospital, Jiaxing Maternity and Child Health Care Hospital and Wuhu No.1 People′s Hospital from August 2018 to January 2021.According to the pertussis etiological testing results, the patients were divided into the pertussis group (65 cases) and non-pertussis group (53 cases). Thirty-three pairs of cases were matched according to age, onset season and city.All nasopharyngeal swabs were tested for infections of other pathogens using FilmArray RP2, which can detect 21 respiratory infection pathogens.The mixed infection rate was compared between groups by Chi- square test. Results:According to the FilmArray RP2 test results, 56.9%(37/65) cases in pertussis group and 15.1%(8/53) cases in the non-pertussis group were positive for multiple pathogens, and the difference was statistically significant ( χ2=21.651, P<0.001). The top 5 mixed infection pathogens in pertussis infants were human rhinovirus/enterovirus (HRV/EV) (38.5%, 25/65), parainfluenza virus (PIV) (18.5%, 12/65), respiratory syncytial virus (RSV) (10.8%, 7/65), coronavirus (Cov) (10.8%, 7/65), and adenovirus (ADV) (7.7%, 5/65). The mixed infection rates of the pertussis group in spring, summer, autumn and winter were 46.2% (6/13), 58.3%(14/24), 55.6%(5/9), and 63.2%(12/19), respectively.Comparison of matched and unmatched cases achieved similar results. Conclusions:Among clinical suspected pertussis infant specimens, the mixed infection rate in confirmed cases is tremendously higher than that in non-pertussis infants.The main mixed infection pathogens in pertussis infants are HRV/EV, PIV, RSV, Cov, and ADV.Mixed infection in pertussis children commonly occurs in four seasons, with the highest incidence in winter.

Objective:To evaluate the relationship between the Panton-Valentine leukocidin (pvl) strain and clinical characteristics, and to describe the molecular biological characteristics of invasive Staphylococcus aureus ( S. aureus) infected clinical isolates. Methods:The isolates of S. aureus caused by invasive infection were collected in Beijing Children's Hospital Affiliated to Capital Medical University from January 2016 to December 2019, and the clinical data of the corresponding children were collected retrospectively using electronic medical records. Multilocus sequence typing, spa typing and pvl gene were analyzed using the PCR. In addition, the minimum inhibitory concentrations (MIC) of antibiotics of all isolates were detected by the micro-broth dilution method, and the isolates were divided into the pvl+ and pvl- groups according to whether or not the S. aureus isolates carried pvl. The t test and the Mann-Whitney U test were used to compare the clinical symptoms between the pvl+ and pvl- groups. Chi-square test was used to compare the drug susceptibility between the two isolates. Results:A total of 127 cases of invasive S. aureus infection were collected during the study period. The white blood cell count, neutrophil count, and C-reaction protein level in the pvl+ group were significantly higher than those in the pvl- group ( P=0.001, P=0.001, P=0.005). The rate of pvl carrier was 44.9%. Among 57 pvl+ pathogenic strains, 64.9% (37/57) were MRSA. The multidrug resistance rate of pvl- isolates was higher than that of pvl+ isolates (70% vs. 49.12%, P=0.02). Conclusions:In invasive S. aureus infection, pvl+ strain is associated with elevated inflammatory markers in children. the positive rate of pvl is higher in clinical isolates, and the multidrug resistance rate of pvl- S. aureus is higher.