Objective To investigate the genotype and mutation frequency of thalassemia in child patients of Shenzhen region so as to provide evidences for the gene diagnosis and genetic counseling of thalassemia.Methods A total of 1 206 child patients suspected with thalassemia were retrospectively analyzed.The gene deletion of α-thalassemia was detected by Gap-PCR.The point mutations of α-thalassemia and β-thalassemia were determined by reverse dot blot(RDB)-PCR.The specimens suspected with HKαα and rare gene mutations were determined with nested PCR and gene sequencing,respectively.Results The detection rate of thalassemia was 76.9％ (927/ 1 206).Among them,α-thalassemia accounted for 40.5％ (489/1 206),and--SEA/αα was the most common gene mutation(75.1％);β-thalassemia accounted for 33.7％ (406/1 206),and the main IVS-2-654 (C→T) and CDM1-42 (-TCTT) heterozygous mutations accounted for 35％ and 32.5％,respectively.In addition,there were 32(2.7％) β-thalassemia patients with α-thalassemia mutation,1 patient with HKαα/ααQS,1 α-thalassemia patient with CD61 (AAG→TAG)/--SEA and 1 β-thalassemia patient with CD5 (CCT→C).Conclusion The are complicated gene mutation types and rare gene mutations of thalassemia in child patients of Shenzhen region.

Objective To analyze the etiological characteristics and the variation of pathogens spectrum in hospitalized children with a-cute respiratory tract infection(ARTI)before and after COVID-19 under"the level B of management for class B"of infectious diseases(Level B for Class B)in Shenzhen,in order to provide reference for the clinical diagnosis,treatment and prevention of ARTI.Meth-ods The ARTI cases from January 8,2022 to July 30,2022 were selected as before"Level B for Class B",and the cases from Janu-ary 8,2023 to July 30,2023 were selected as after"Level B for Class B".The pharyngeal swab samples submitted for analyzing 11 common pathogens,such as COVID-19,influenza virus(Ⅳ),respiratory syncytial virus(RSV)and mycoplasma pneumoniae(MP)in the children with ARTI admitted to Shenzhen Children's Hospital.Results SARS-CoV-2 were detected as positive in 347 cases,a-mong which 225 cases were before"Level B for Class B"including 29 cases combined with other pathogens(12.89％,29/225)and human parainfluenza viruses(HPIV)was the most common(31.03％,9/29).After"Level B for Class B",SARS-CoV-2 were detec-ted as positive in 122 cases,including 28 cases combined with other pathogens(22.95％,28/122),and RSV was the most common(28.57％,8/28).There was a statistical difference between the positive rate of SARS-CoV-2 combined with other pathogens before and after"Level B for Class B"(X2=5.834,P=0.016).After"Level B for Class B",the total pathogen detection rate(positive for at least one pathogen)was 60.82％(2 864/4 709)in the spring(January 8,2023 to April 30,2023),and influenza virus A(IVA)(22.64％,1 066/4 709),rhinovirus(HRV)(19.86％,935/4 709)and RSV(13.29％,626/4 709)were the main pathogens,and there were 301 cases(6.39％,301/4 709)of mixed infections.In the summer(May 1,2023 to July 30,2023),the total detection rate of pathogens was 70.26％(4 012/5 710),among which RSV(21.63％,1 235/5 710),MP(13.91％,794/5 710),HPIV(10.05％,574/5 710)were the main pathogens,and there were 710 cases(12.43％,710/5 710)of mixed infections,all of which were significantly higher than the same period before"Level B for Class B".The difference was statistically significant(P＜0.05).Conclusion After"Level B for Class B"for COVID-19,the detection rate of 11 common pathogens increased significantly and the pathogen spectrum of ARTI changed significantly.