Harnessing CRISPR-Cas12 and Microfluidics Chips for Multiplex Respiratory Pathogens Diagnosis.

To investigate the status and epidemiological characteristics of respiratory pathogens infections in children with influenza-like illnesses (ILI) in Beijing Children's Hospital from 2022 to 2023. A dual amplification technique was used to detect nucleic acids of seven common respiratory pathogens, including influenza A virus (Flu A), influenza B virus (Flu B), mycoplasma pneumoniae (MP), respiratory syncytial virus (RSV), parainfluenza virus (PIV), adenovirus (ADV), and Chlamydia pneumoniae (CP), in outpatient and inpatient children (aged 0-18 years) with influenza-like symptoms who sought medical care at Beijing Children's Hospital, from January 2022 to March 2023. A total of 43 663 children were included in the study, of which 27 903 tested positive for respiratory pathogens with a total detection rate of 63.91%. Flu A had the highest detection rate of 69.93% (27 332/39 084), followed by MP about 13.22% (380/2 875). The total detection rate of RSV, PIV and ADV was 7.69% (131/1 704). Flu B had a detection rate of 0.16% (64/39 084). No CP was detected in this study. A total of 7 cases of dual infections were detected, with a detection rate of 0.41% (7/1 704). The Chi-square test was used to analyze the differences in detection rates of pathogens among different genders, age groups, and different seasons. Among the seven pathogens, only Flu A had statistically significant differences in gender (χ2=16.712, P<0.001). The detection rates of Flu A and MP showed an increasing trend with age (both P trend<0.001), while the detection rates of RSV and PIV showed a decreasing trend with age (both P trend<0.001). Flu A had its epidemic peak in winter and spring, with detection rates of 61.30% (3 907/6 374) and 77.47% (23 207/29 958) respectively; MP and PIV had higher detection rates in autumn (25.14% and 7.64% respectively); RSV showed a relatively higher detection rate in winter (8.69%); Flu B and ADV had lower detection rates throughout the study period (0.16% and 1.17% respectively). In conclusion, children with ILI in 2022-2023 were mainly infected with a single respiratory pathogen, and occasionally dual pathogen infections were observed. Among them, the detection rate of Flu A was the highest, and only Flu A showed a gender difference in detection rate. As the age of the children patients increased, the detection rate of Flu A and MP showed an increasing trend, while RSV and PIV showed a decreasing trend. The prevalence of Flu A, Flu B, MP, PIV, and RSV were seasonal.

Objective: To analyze the distribution and epidemiological characteristics of common non-bacterial pathogens in hospitalized children with acute respiratory tract infections(ARTI)from a multi-center study covering 4 regions in Fujian Province in 2023. Methods: A retrospective cohort study was conducted using medical record analysis.A total of 22 769 hospitalized children with ARTI were enrolled from January to December 2023 across seven regional pediatric medical centers in Fujian Province (covering four major geographical divisions of Fuzhou, Nanping, Sanming and Longyan; all selected hospitals were regional children's medical centers).Using single-tube multiplex PCR with fragment analysis on a Sanger sequencing platform, the nucleic acids of 11 common non-bacterial respiratory pathogens were tested in nasopharyngeal swabs collected from 22 769 children. These pathogens included influenza A virus(FluA), influenza B virus(FluB), parainfluenza virus(PIV), respiratory syncytial virus (RSV), adenovirus (ADV), human rhinovirus (HRV), human bocavirus (HBoV), human coronavirus (HCoV), human metapneumovirus(HMPV), Mycoplasma pneumoniae(MP), and Chlamydia (Ch). Count data were described as [n(%)], and the chi-square test/Fisher's exact test was used to compare the differences in rates between groups. Epidemiological features, including positive detection rates, pathogen profiles, and correlations with region, sex, age and month, were analyzed. Results: Among 22 769 children with ARTI, pathogens were detected in 16 213 cases (71.21%), including 13 340 single infections (58.59%).The detection rates of single pathogens in descending order were human rhinovirus (HRV, 12.95%), Mycoplasma pneumoniae(MP, 12.27%), respiratory syncytial virus(RSV, 11.12%), influenza A virus (Flu-A, 7.98%), parainfluenza virus(PIV, 4.66%), human metapneumovirus(HMPV, 4.60%), adenovirus(ADV, 2.70%), human bocavirus(HBoV, 0.84%), human coronavirus(HCoV, 0.82%), influenza B virus(Flu-B, 0.47%) and Chlamydia(Ch, 0.18%).Mixed infections occurred in 2 873 cases(12.62%), primarily dual infections(2 679 cases).Regional analysis revealed significant disparities:Luoyuan County Hospital (Fuzhou) exhibited the highest total detection rate(86.59%, 1 414/1 633)and mixed infection rate(23.27%, 380/1 633)(both P<0.001), with notably elevated MP (26.39%, 431/1 633);Jian'ou City Hospital(Nanping) ranked second for Flu-A(14.21%, 409/2 879), RSV(13.20%, 380/2 879) and mixed infections(17.12%, 493/2 879);Lianjiang County Hospital(Fuzhou) showed distinct prevalence of Flu-A(10.68%, 130/1 217), PIV(6.00%, 73/1 217), and HBoV(1.73%, 21/1 217); Yong'an City Hospital (Sanming) reported high MP (26.07%, 238/913) and RSV(12.38%, 113/913);Shaowu City Hospital(Nanping) was dominated by MP (18.60%, 407/2 188) and HRV(13.39%, 293/2 188); Tingzhou Hospital(Longyan) had the highest HRV (17.88%, 407/2 276) and Flu-B (0.75%, 17/2 276); and Fuzhou Children's Hospital showed elevated ADV(3.38%, 394/11 663) and HCoV(1.08%, 126/11 663). Except for Flu-B(0.47%, 108/22 769;P=0.054) and Ch(0.18%, 40/22769; P=0.900), all pathogens and mixed infections exhibited significant regional variations (P<0.05).Gender analysis indicated higher detection rates of HRV, RSV, Flu-A, ADV, PIV, HBoV and mixed infections in males, while MP, HMPV, Flu-B, HCoV, and Ch were more prevalent in females, with statistically significant differences for HRV and MP (both P<0.001). Age stratification showed the highest overall detection rate in the 3-<6 years group (75.48%;P<0.001): RSV and Ch peaked in infants (<1 year), HRV, PIV, ADV and HBoV in toddlers (1-<3 years), HMPV, HCoV, and mixed infections in preschool children (3-<6 years), and MP, Flu-A and Flu-B in older children (6-<18 years).Analyzing the prevalent months, the monthly prevalence trends of pathogens in various regions are similar.Seasonal trends demonstrated year-round HRV activity (peaking in spring/autumn), MP prevalence in autumn/winter, RSV surges in spring-summer (April-June) and late summer-autumn (August-October), and Flu-A predominanced in winter-spring. Conclusion: Multiplex PCR with fragment analysis demonstrated high diagnostic efficacy. The top 4 non-bacterial pathogens in Fujian Province's ARTI-hospitalized children in 2023 were HRV, MP, RSV and Flu-A. Pathogen distribution exhibited significant regional, age and seasonal variations, emphasizing the need for targeted prevention strategies.

BackgroundThis study analyzed the results of seven respiratory pathogen tests to investigate their epidemiological characteristics in children and provide clinical evidence for the prevention and control of acute respiratory infections (ARIs) in the pediatric population of Shanghai.MethodsThe test results for the seven pathogens (influenza A virus (FLUA), influenza B virus (FLUB), parainfluenza virus (PIV), adenovirus (ADV), respiratory syncytial virus (RSV), Mycoplasma pneumoniae (MP) and Chlamydia pneumoniae (CP)) were collected from 40,606 pediatric patients exhibiting clear ARI symptoms at Shanghai Children’s Medical Center, affiliated with Shanghai Jiao Tong University School of Medicine from January 2018 to December 2023 and retrospectively analyzed. Statistical analyses were conducted on positive detection rates, infection patterns, epidemic periods and variations based on sex and age.ResultsThe overall positive detection rate for the seven respiratory pathogens was 22.57%. Compared with those in 2018, 2019 (pre-COVID-19) and 2023 (post-COVID-19), the rate significantly decreased during the pandemic period (2020–2022) (P*<0.05), with mono-infections (mostly due to RSV, MP and PIV) being predominant. The epidemic periods of several pathogens shifted significantly after the pandemic. ADV (2.33%) and MP (14.52%) showed the highest positive detection rates among children aged 3 to < 6 years and 6 to < 12 years, respectively. Additionally, FLUA (1.46%) and FLUB (0.59%) exhibited the lowest rates in children aged 0 to < 3 years, while PIV (5.11%) and RSV (9.88%) showing the highest rates in the same age range. Finally, the positive detection rate of MP was significantly higher in girls (6.93%) than in boys (6.18%) (P*<0.05).ConclusionsThe overall positive detection rate for the seven respiratory pathogens decreased significantly during the pandemic (2020–2022), with several pathogens showing notable shifts in their pre- and post-pandemic epidemic periods. MP, RSV and PIV were identified as the primary ARI-causing pathogens in children, and age- or sex-related differences also observed. This study enhances current understanding of the epidemiological characteristics of respiratory pathogen infections among children spanning the pre-, during, and post-COVID-19 periods, and provides critical insights for developing more effective prevention and control strategies in Pudong, Shanghai.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12985-025-03062-5.

Mycoplasma pneumoniae (MP) is an important pathogen associated with respiratory tract infections. Macrolide-resistant MP infections (which mainly contain the A2063G mutation in their 23S rRNA) contribute to severe cases, complications, and sequelae development. Therefore, the development of a sensitive, rapid, and accurate method for MP detection and its A2063G mutation is critical for early differential diagnosis and for guiding clinical medication. Herein, we establish a one-step, highly efficient, and specific fluorescence-based detection system for the MP nucleic acid using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas13a combined with recombinase polymerase amplification (RPA) isothermal technology. A detection limit of 5 copies/μL within 40 min was achieved using this system. When applied to 57 clinical specimens, this method exhibited a sensitivity of 96.3% and a specificity of 100% compared with quantitative real-time polymerase chain reaction (PCR). We also developed a two-step detection system for macrolide-resistant mutations with a sensitivity of 10 copies/μL. The RPA-CRISPR/Cas13a system was further applied to detect 27 clinical specimens, and the results were consistent with the sequencing data. Additionally, the RPA-CRISPR/Cas13a detection system was integrated with lateral flow assay (LFA) technology to develop an LFA-RPA-CRISPR/Cas13a detection system. In conclusion, our RPA-CRISPR/Cas13a detection system enabled rapid, sensitive, and highly efficient detection of MP and its mutation. This new method provides an efficient tool for clinical and point-of-care testing (POCT) to facilitate early treatment and infection control.IMPORTANCEA rapid, sensitive, and highly efficient nucleic acid detection system for Mycoplasma pneumoniae (MP) was developed in this study by integrating clustered regularly interspaced short palindromic repeats (CRISPR)/Cas13a with recombinase polymerase amplification (RPA) technology. A two-step assay based on this technology was then further developed to identify the A2063G mutation in the 23S rRNA gene of MP that was associated with macrolide resistance. The proposed system was then validated using clinical samples, and it demonstrated consistency with conventional diagnostic and sequencing results. Therefore, the RPA-CRISPR/Cas13a system enabled rapid, sensitive, and cost-effective detection of MP and its drug resistance mutation. This method is a robust tool for clinical and point-of-care testing (POCT) applications. These systems will facilitate early treatment and infection control of MP.

Acute respiratory tract infections (ARTIs) are the leading cause of morbidity and death in children < 5 years worldwide. The aim of this study is to analyze the seroprevalence of nine pathogen specific IgMs in children with ARTIs with respect to gender, age, and seasonality in the Guangzhou region. Serum samples were collected from 20160 children with ARTIs admitted to the Guangzhou Women and Children's Medical Center between 2011 and 2012. Serum-specific IgM antibodies to nine respiratory pathogens, Mycoplasma pneumonia (MP), Legionella pneumophila (LP), Coxiella burnetii (C. burnetii), Chlamydophila pneumonia (CP), adenovirus (ADV), respiratory syncytial virus (RSV), type A and type B influenza virus (IVA and IVB), and parainfluenza virus (PIV), were detected using immunofluorescence assay. The male-to-female ratio of all patients was 1.9:1. The median age was 3 years and 8 months with a significant difference in seropositivity to respiratory tract pathogens between children from different age groups. Seropositivity was detected in 43.53% of the children with the top three pathogens being MP (33.15%), RSV (10.27%), and ADV (6.63%), followed by IVB (2.63%), LP (2.25%), IVA (1.59%), PIV (1.57%), CP (0.27%), and C. burnetii (0.13%). The prevalence of single, double, and triple seropositivity was 70.20% (6160/8775), 25.22% (2213/8775), and 4.57% (401/8775), respectively. The total IgM seropositivity for any kind of pathogen in the nine kinds of pathogens peaked in winter (46.53%), while the nadir was observed in summer (41.97%). The top three seroprevalence of nine kinds of pathogen specific IgM was MP, followed by RSV and ADV. The epidemic pathogen specific IgM had a season-specific seropositivity distribution. Seroprevalence of the pathogen should be a focus of attention.

After ending the three-year zero COVID policy in China, the epidemiology of other respiratory pathogens has been affected. This study aimed to characterize of common respiratory pathogen infections in pediatric patients hospitalized for acute respiratory tract infections (ARTIs) in Suzhou before and after ending the zero COVID policy. Nasopharyngeal aspirates (NPAs) were obtained from children with ARTIs (aged ≤ 16 years) at the Children’s Hospital of Soochow University for the detection of respiratory syncytial virus (RSV), influenza A (FluA), FluB, human parainfluenza virus (HPIV), adenovirus (ADV), human rhinovirus (HRV), bocavirus (BoV), human metapneumovirus (HMPV), and mycoplasma pneumoniae (MP). The data were compared between two periods: January 2020 to December 2022 (before ending the zero COVID policy) and January 2023 to May 2024 (after ending the zero COVID policy). Patients were divided into four groups: 0–2, ≥ 3–5, ≥ 6–10, and ≥ 11–16 years. A total of 42,379 patients were enrolled and the top four pathogens identified were MP, HRV, RSV and HPIV with positive rates of 20.2%, 19.5%, 15.1%, and 6.9%, respectively. A total of 28,352 positive cases were detected, with positive rates of 54.0% (n = 11,850/21,941) and 80.7% (n = 16,502/20,438) before and after ending the zero COVID policy, respectively. Total RSV, HRV, HPIV, and MP positivity increased by 27.8%, 39.0%, 12.3%, and 322.7%, respectively, after ending the zero COVID policy compared to positivity before the policy. After ending the zero COVID policy, the positive rates of RSV, HRV, and HPIV increased most in children aged 0–2 years, with increases by 88.8% (OR: 2.3, 95% CI: 2.2–2.5), 50.0% (OR: 1.6, 95% CI: 1.5–1.7), and 69.6% (OR: 1.8, 95% CI: 1.6-2.0), respectively. The greatest increase in MP positivity was 316.9% in the 3–5 years (OR: 5.5, 95% CI: 4.9–6.1). After ending the zero COVID policy, the RSV-positive rate increased most in summer, while HRV was predominantly circulated in spring and the MP-positive rate peaked in autumn. Ending the zero COVID policy facilitated the transmission of common respiratory pathogens in children. Post-pandemic surveillance and control of respiratory pathogens must be strengthened to reduce health risks.

Community-acquired respiratory viruses

ObjectiveTo analyze the epidemic characteristics of common respiratory tract infection pathogens in children with respiratory tract infection, and provide scientific basis for the prevention and control of respiratory tract infection.MethodsA retrospective collection of clinical data was conducted on 11,538 children with respiratory tract infections at Luoyang Maternal and Child Health Hospital from December 2022 to November 2023. The types of respiratory tract infections, including upper and lower respiratory tract infections, as well as five respiratory pathogens: influenza A virus (influenza A), influenza B virus (influenza B virus, adenovirus (ADV), respiratory syncytial virus (RSV), and Mycoplasma pneumoniae (MP) infections, were analyzed and compared for different genders, ages, temperatures, and air quality in different months; And the changes of five pathogens in children with respiratory tract infections of different disease severity.ResultsFrom December 2022 to November 2023, a total of 11,538 children with respiratory infections were included in the analysis, including 6436 males and 5102 females, with an age of 4.92 ± 2.03 years. The proportion of upper respiratory tract infections is as high as 72.17%, and lower respiratory tract infections account for 27.83%. Among them, 2387 were positive for Flu A antigen, with a positive rate of 20.69%, 51 cases were positive for Flu B antigen, and the positive rate was 0.4%, 1296 cases were positive for adv antigen, with a positive rate of 11.23%, 868 cases were positive for RSV antigen, with a positive rate of 7.52%, 2481 cases were positive for MP IgM antibody or MP antigen, and the positive rate was 21.50%. Flu B in male children The infection rate of ADV and MP was higher than that of female children (p < 0.05); Among children in different age groups, the older the age, the older the Flu A The higher the infection rate of MP (p < 0.05), the higher the positive rate of RSV in children with younger age (p < 0.05). The positive rate of ADV in children aged 3–6 years and > 6 years was higher than that in children aged 0–3 years (p < 0.05); Flu A and MP are popular throughout the year, and the positive rate peaks during the period of temperature rise and air quality decline from February to March, and during the period of temperature drop and air quality index rise from August to November, The positive rate of RSV peaked after the turning point of temperature rise from March to April. The infection rate was higher during the period of sharp decline in air quality from March to May and sharp decline in temperature in November, The positive rate of ADV was higher at the turning point of temperature rise from February to March, and then the infection rate decreased. During the period of sharp temperature drop from August to November, the positive rate increased sharply, and the peak of infection occurred; As the disease worsens, The positive rates of Flu A, Flu B, RSV, MP and combined infection with more than two pathogens were all increased (p < 0.05).ConclusionAfter the new coronavirus epidemic in 2022, Flu A and MP have the highest infection rate of respiratory pathogens in children, showing a peak growth in general, with epidemic characteristics changing with environmental temperature, air quality and seasons. The main disease type is upper respiratory tract infection, MP and adv infections were mainly in male children, Flu A, MP and ADV infections are more common in older children, RSV infection was more common in younger children; Flu A, Flu B, RSV and MP infection and the co infection of more than two pathogens may more easily lead to the occurrence of severe pneumonia.

This study aims to evaluate the impact of non-pharmaceutical interventions (NPIs) on the prevalence of respiratory pathogens among hospitalised children with acute respiratory infections (ARIs) in Suzhou. Children with ARIs admitted to the Children’s Hospital of Soochow University between 1 September 2021 and 31 December 2022 and subjected to 13 respiratory pathogen multiplex PCR assays were included in the study. We retrospectively collected demographic details, results of respiratory pathogen panel tests, and discharge diagnostic information of the participants, and described the age and seasonal distribution of respiratory pathogens and risk factors for developing pneumonia. A total of 10,396 children <16 years of age, including 5,905 males and 4,491 females, were part of the study. The positive rates of the 11 respiratory pathogen assays were 23.3% (human rhinovirus (HRV)), 15.9% (human respiratory syncytial virus (HRSV)), 10.5% (human metapneumovirus (HMPV)), 10.3% (human parainfluenza virus (HPIV)), 8.6% (mycoplasma pneumoniae (MP)), 5.8% (Boca), 3.5% (influenza A (InfA)), 2.9% (influenza B (InfB)), 2.7% (human coronavirus (HCOV)), 2.0% (adenovirus (ADV)), and 0.5% (Ch), respectively. Bocavirus and HPIV detection peaked during the period from September to November (autumn), and MP and HMPV peaked in the months of November and December. The peak of InfA detection was found to be in summer (July and August), whereas the InfB peak was observed to be in winter (December, January, and February). HRSV and HRV predominated in the <3 years age group. HRV and HMPV were common in the 3–6 years group, whereas MP was predominant in the ≥6 years group. MP (odds ratio (OR): 70.068, 95%CI: 32.665–150.298, P < 0.01), HMPV (OR: 6.493, 95%CI: 4.802–8.780, P < 0.01), Boca (OR: 3.300, 95%CI: 2.186–4.980, P < 0.01), and HRSV (OR: 2.649, 95%CI: 2.089–3.358, P < 0.01) infections were more likely to develop into pneumonia than the other pathogens. With the use of NPIs, HRV was the most common pathogen in children with ARIs, and MP was more likely to progress to pneumonia than other pathogens.

Underestimation of Influenza Viral Infection in Childhood Asthma Exacerbations

Respiratory tract infection is one of the most common reasons for both morbidity and mortality worldwide. High attention has been paid to the etiological tracing of respiratory tract infection since the advent of COVID-19. In this study, we aimed to evaluate the epidemiological features of pathogens in respiratory tract infection, especially during COVID-19 pandemic. A total of 7668 patients with respiratory tract infection who admitted to Qilu Hospital of Shandong University from March 2019 to Dec 2021 were retrospectively included. The respiratory tract specimens were detected using a commercial multiplex PCR-based panel assay for common respiratory pathogens including influenza A virus (Flu-A), influenza A virus H1N1 (H1N1), influenza A virus H3N2 (H3N2), influenza B virus (Flu-B), parainfluenza virus (PIV), respiratory syncytial virus (RSV), adenovirus (ADV), Boca virus (Boca), human Rhinovirus (HRV), Metapneumovirus (MPV), Coronavirus (COV), Mycoplasma pneumoniae (MP), and Chlamydia (Ch). The positive rates were compared using a chi-square test. Compared with 2019, the positive rate of pathogen detection during from January 2020 to December 2021 was significantly lower, especially the detection of Flu-A. The positive rate of respiratory pathogen strains was 40.18% during COVID-19 pandemic, and a total of 297 cases (4.69%) of mixed infection with two or more pathogens were detected. There was no statistical difference in the positive rate between male and female patients. However, the positive rates of infection were different among different age groups, with higher incidence of RSV in infancy and toddler group, and MP infection in children and teenager group. While, HRV was the most common pathogen in the adult patients. Moreover, Flu-A and Flu-B were higher in winter, and MP and RSV were higher in spring, autumn and winter. The pathogens such as ADV, BOCA, PIV, and COV were detected without significant seasonal distribution. In conclusion, respiratory pathogen infection rates may vary by age and season, regardless of gender. During the COVID-19 epidemic, blocking transmission routes could help reduce the incidence of respiratory tract infection. The current prevalence of respiratory tract infection pathogens is of great significance for clinical prevention, diagnosis and treatment.

This retrospective study analyzed epidemiological features of infections by 13 common respiratory pathogens among children in Shenzhen, China, from January 2020 to February 2025. A total of 73,886 throat swabs from pediatric patients with suspected respiratory infections were tested using multiplex fluorescence PCR-capillary electrophoresis. Human rhinovirus (HRV), respiratory syncytial virus (RSV), Mycoplasma pneumoniae (MP), and human parainfluenza virus (HPIV) were the most prevalent, with positive rates of 24.57%, 12.46%, 11.46%, and 6.86%, respectively. Pathogen positivity rates significantly differed between the coronavirus disease 2019 (COVID-19) pandemic (2020-2022) and post-relaxation period (2023-2025) (P < 0.0001). Seasonal patterns shifted: HPIV peaked in summer, HRV in autumn-winter, MP in summer-autumn, and RSV in spring. After control measures eased, positivity increased across all age groups. HPIV was highest in children aged 6 months to 1 year, HRV in 3-6 years, MP in >6 years, and RSV in 0-6 months. Age- and sex-related differences were significant (all P < 0.001). These findings indicate that evolving COVID-19 mitigation strategies have altered epidemiological patterns, highlighting the need for targeted prevention considering high-risk groups, co-infections, and seasonality.IMPORTANCEThis large-scale pediatric study reveals how coronavirus disease 2019 control measures and their relaxation reshaped respiratory pathogen epidemiology in Southern China. We identified major shifts in seasonal peaks, age-specific susceptibility, and overall infection prevalence, particularly for human rhinovirus, respiratory syncytial virus, Mycoplasma pneumoniae, and human parainfluenza virus. The narrowing or shifting of epidemic windows implies altered transmission dynamics, likely driven by nonpharmaceutical interventions and subsequent immunity gaps. The significant post-relaxation surge across all age groups underscores the vulnerability of children to multiple pathogens once restrictions ease. These findings provide crucial evidence for optimizing pediatric respiratory infection surveillance and designing adaptive, season- and age-specific prevention strategies to mitigate future outbreaks.

Objective To study the etiology of comumunity acquired pneumonia (CAP) in children of Jiaxing city and provide the basis for the clinical diagnosis and treatment.Methods An etiological study was performed on 800 young children with CAP in Jinxing First Hospital from Jan 2008 to Dec 2010.Sputum samples were collected for isolating bacteria and checking the antigen of respiratory syncytial virus ( RSV),adenovirus ( ADV),influenza virus (IV) and parainfluenza virus ( PIV ).IgM antibodies of mycoplasma pneumoniae (MP),ADV,W and PIV paired serum samples were detected.The 202 cases with positive etiology were divided into three groups:bacteria group ( 109 cases),virus group (54 cases) and MP group (39 cases).The leukocyte,C-reactive protein (CRP) and procalcitonin (PCT) were detected.Results The etiology of CAP was identified in 202 (25.25％) children of all the 800 cases,the distribution of causal agents was as follows:Streptococcus pneumoniae in 46 cases (22.77％,46/202 ),Haemophilus influenzae in 32 cases (15.84％,32/202),Staphylococcus in 5 cases (2.48％,5/202),Klebsiella pneumoniae in 8 cases (3.96％,8/202),Escherichia coli in 12 cases (5.94％,12/202),MP in 39 cases ( 19.31％,39/202),RSV in 48 cases (23.76％,48/202),ADV in 1 case (0.50％,1/202),IV in 3 cases ( 1.49％,3/202),and PIV in 2 cases ( 0.99％,2/202 ),Streptococcus pneumoniae and RSV mixed infection in 3 cases ( 1.49％,.3/202),Streptococcus pneumoniae and MP mixed infection in 3 cases ( 1.49％,3/202).RSV infection occured mainly in infants less than 1-year-old,Streptococcus pneumoniae oceured in all ages but was mostly in 1 ～ 3years,Haemophilus influenzae infection occured mainly in infants less than 3-year-old,MP infection occured mainly in infants more than six years.The PCT levels of the three groups were (7.78 ±6.14) ng/ml,(0.39 ±0.56) ng/ml,and (0.20 ±0.34) ng/ml,respectively.There were significant differences among the three groups ( P ＜ 0.05 ).Conclusion RSV infection occurs mainly in infants of age less than 1 year,Streptococcus pneumoniae and Haemophilus influenzae infection occur mainly in infants of age 1 ～3 years,while MP is the leading cause of pneumonia in children of age more than 6 years in Jiaxing city.We can decide pathogen on ages,clinical manifestation and PCT level to guide the rational use of drugs. Key words: Community acquired pneumonia; Pathogenic analysis ; Procaicitonin; Children

Objective To investigate the latest three years’ distribution of 9 kinds of respiratory viruses from respiratory tract infection patients in the first people’s hospital of Xinxiang. Methods Data of 1 482 in- and out-patients underwent virus antibody detection were retrospectively analyzed. Results Among the total 1 482 patients, 559 cases (37.72%) were positive, including 366 cases (24.70%) of mycoplasma pneumoniae (MP), 177 cases (11.94%) of legionella pneumoniae (LP), 126 cases (8.50%)of influenza B virus (INFB), 69 cases (4.66%) of parainfluenza virus (PIVs), 61 cases (4.12%) of influenza A virus (INFA), 28 cases (1.89%) of adeno-virus (ADV), 23 cases (1.55%) of respiratory syncytial virus (RSV), 22 cases (1.48) of chlamydia pneumoniae (CPn), and 16 cases (1.08%) of Q fever rickettsia (COX). The MP positive rate increased in summer (P<0.05), and PIVs increased in spring (P<0.01). In 0 to 14 age group, LP, MP and INFB positive rate were higher than other age groups(P<0.05 or P<0.01). In addition, MP, INFB and PIVs positive rate in women was higher than men(P<0.05). Conclusions MP, LP and INFB are mainly respiratory tract infection pathogens in Xinxiang, and the distribution of respiratory tract infection pathogens is correlated with season, age and gender. Key words: Respiratory tract infection; Pathogens; IgM antibody; Distribution

The patterns of respiratory pathogens have undergone significant changes, underscoring the critical need for accurate pathogen identification to guide targeted treatment. This study aimed to investigate the positive rates of common respiratory pathogens over the past two years using the multiplex molecular testing in clinical settings. This study evaluated respiratory pathogens in 7861 hospitalized patients at Qilu Hospital of Shandong University from March 2022 to February 2024. Pathogen detection was performed using multiplex RT-PCR combined with capillary electrophoresis technology, targeting influenza A virus (Flu-A), influenza A virus H1N1 (H1N1), influenza A virus H3N2 (H3N2), influenza B virus (Flu-B), parainfluenza virus (PIV), adenovirus (ADV), human Metapneumovirus (HMPV), human Coronavirus (HCOV), Mycoplasma pneumoniae (MP), respiratory syncytial virus (RSV), parainfluenza virus (PIV), Boca virus (Boca), human Rhinovirus (HRV), and Chlamydia (Ch). A comparative analysis of epidemiological patterns was conducted between the period during and after implementation of COVID-19 control policies. The overall pathogen detection rate was significantly higher at 65.79% (3786/5754) post COVID-19 pandemic compared to 30.36% (640/2107) during COVID-19 pandemic. With the relaxation of COVID-19 control policies, the positive rates of viruses such as Flu-A, Flu-B, PIV, RSV, and HCOV increased significantly. In contrast, there were no significant differences in the positive rates of HRV and Boca between the two periods. Notably, the positive rate of RSV was significantly higher across all age groups in the post-pandemic COVID-19 period, expect among individuals aged 14-18 and 19-40 years. MP was identified as the predominant pathogen in patients aged 4-13 years. Seasonal variation was evident in the detection rates of respiratory pathogens, ranging from 18.27% in 2022 to 77.79% in 2023. Flu-A H1N1 subtype infections were detected throughout spring, autumn and winter of 2023, peaking in spring and declining gradually in subsequent months. Additionally, MP infections fist emerged in May 2023 and increased monthly, reaching the peak in October of the same year. The findings illustrate the progressive re-emergence and considerable epidemiological importance of multiple respiratory pathogens among hospitalized patients across different age groups and seasons during the two-year surveillance period. Utilizing a multiplex molecular approach for respiratory pathogen surveillance enables accurate assessment of prevalence trends, especially in hospitalized patients with more severe clinical presentations, which can help clinicians to take necessary measures in the management of prevention, control, and precise therapy.