A Multicenter Study of Viral Aetiology of Community-Acquired Pneumonia in Hospitalized Children in Chinese Mainland.

Community-acquired pneumonia (CAP) is one of the leading causes of morbidity and mortality in children worldwide. In this study, we aimed to describe the aetiology of viral infection of pediatric CAP in Chinese mainland. During November 2014 to June 2016, the prospective study was conducted in 13 hospitals. The hospitalized children under 18 years old who met the criteria for CAP were enrolled. The throat swabs or nasopharyngeal aspirates (NPAs) were collected which were then screened 18 respiratory viruses using multiplex PCR assay. Viral pathogens were present in 56.6% (1539/2721) of the enrolled cases, with the detection rate of single virus in 39.8% of the cases and multiple viruses in 16.8% of the cases. The most frequently detected virus was respiratory syncytial virus (RSV) (15.2%, 414/2721). The highest detection rate of virus was in < 6-month-age group (70.7%, 292/413). RSV, human metapneumovirus (HMPV), human parainfluenza viruses (HPIVs) and influenza B virus (Flu B) showed the similar prevalence patterns both in north and south China, but HPIVs, Flu A, human bocavirus (HBoV), human adenovirus (HAdV) and human coronaviruses (HCoVs) showed the distinct circulating patterns in north and south China. Human enterovirus/human rhinovirus (HEV/HRV) (27.6%, 27/98), HBoV (18.4%, 18/98), RSV (16.3%, 16/98) and HMPV (14.3%, 14/98) were the most commonly detected viruses in severe pneumonia cases with single virus infection. In conclusion, viral pathogens are frequently detected in pediatric CAP cases and may therefore play a vital role in the aetiology of CAP. RSV was the most important virus in hospitalized children with CAP in Chinese mainland.

A multi-center study on Molecular Epidemiology of Human Respiratory Syncytial Virus from Children with Acute Lower Respiratory Tract Infections in the Mainland of China between 2015 and 2019.

Human respiratory syncytial virus (RSV) is a major pathogen of acute lower respiratory tract infection among young children. To investigate the prevalence and genetic characteristics of RSV in China, we performed a molecular epidemiological study during 2015-2019. A total of 964 RSV-positive specimens were identified from 5529 enrolled patients during a multi-center study. RSV subgroup A (RSV-A) was the predominant subgroup during this research period except in 2016. Totally, 535 sequences of the second hypervariable region (HVR-2) of the G gene were obtained. Combined with 182 Chinese sequences from GenBank, phylogenetic trees showed that 521 RSV-A sequences fell in genotypes ON1 (512), NA1 (6) and GA5 (3), respectively; while 196 RSV-B sequences fell in BA9 (193) and SAB4 (3). ON1 and BA9 were the only genotypes after December 2015. Genotypes ON1 and BA9 can be separated into 10 and 7 lineages, respectively. The HVR-2 of genotype ON1 had six amino acid changes with a frequency more than 10%, while two substitutions H258Q and H266L were co-occurrences. The HVR-2 of genotype BA9 had nine amino acid substitutions with a frequency more than 10%, while the sequences with T290I and T312I were all from 2018 to 2019. One N-glycosylation site at 237 was identified among ON1 sequences, while two N-glycosylation sites (296 and 310) were identified in the 60-nucleotide duplication region of BA9. To conclusion, ON1 and BA9 were the predominant genotypes in China during 2015-2019. For the genotypes ON1 and BA9, the G gene exhibited relatively high diversity and evolved continuously.

Molecular Characteristics of Human Adenovirus Type 3 Circulating in Parts of China During 2014-2018.

Human adenoviruses (HAdVs) are important pathogens causing respiratory infections; 3.5-11% of childhood community-acquired pneumonia is associated with HAdV infection. Human adenovirus type 3 (HAdV-3), leading to severe morbidity and mortality, is one of the most prevalent genotype among adenoviruses responsible for acute respiratory infections (ARIs) in children in China. To identify the genetic variation of HAdV-3 in children with ARIs in China, a molecular epidemiological study was conducted. A total of 54 HAdV-3 isolated strains were obtained from children with ARIs in Beijing, Wenzhou, Shanghai, Shijiazhuang, Hangzhou, Guangzhou, and Changchun from 2014 to 2018. Thirty-two strains of which were selected for whole-genome sequencing, while the hexon, penton base, and fiber genes were sequenced for remaining strains. Bioinformatics analysis was performed on the obtained sequences. The phylogenetic analyses based on whole-genome sequences, major capsid protein genes (hexon, penton base, and fiber), and early genes (E1, E2, E3, and E4) showed that the HAdV-3 strains obtained in this study always clustered together with the reference strains from Chinese mainland, while the HAdV-3 prototype strain formed a cluster independently. Compared with the prototype strain, all strains possessed nine amino acid (AA) substitutions at neutralization antigenic epitopes of hexon. The homology models of the hexon protein of the HAdV-3 prototype and strain BJ20160214 showed that there was no evident structural change at the AA mutation sites. Two AA substitutions were found at the Arg-Gly-Asp (RGD) loop and hypervariable region 1 (HVR1) region of the penton base. A distinct AA insertion (20P) in the highly conserved PPPSY motif of the penton base that had never been reported before was observed. Recombination analysis indicated that partial regions of protein IIIa precursor, penton base, and protein VII precursor genes among all HAdV-3 strains in this study were from HAdV-7. This study showed that the genomes of the HAdV-3 strains in China were highly homologous. Some AA mutations were found at antigenic sites; however, the significance needs further study. Our data demonstrated the molecular characteristics of HAdV-3 circulating in China and was highly beneficial for further epidemiological exploration and the development of vaccines and drugs against HAdV-3.

Genetic variations in the fusion protein of respiratory syncytial virus isolated from children hospitalized with community-acquired pneumonia in China.

To identify the variations in fusion (F) protein gene of RSV in China, a molecular epidemiological study was conducted. A total of 553 RSV positive specimens were collected from 2338 pediatric patients hospitalized with community-acquired pneumonia during a multi-center study conducted during 2014-2016. A total of 252 samples (183 RSV A, 69 RSV B) were selected for F gene sequencing, and analyzed together with 142 F gene sequences downloaded from GenBank. The result showed that all the Chinese RSV A and RSV B strains could be divided respectively into three branches. Compared with RSV A/B prototype sequences respectively, there were significant amino acid (AA) mutations at multiple antigenic sites. For RSV A, changes were found at AA residues 122, 124, 125, 276 and 384, and for RSV B at AA residues 45, 116, 125, 172, 173 and 202. Variations in human histocompatibility leukocyte antigen-restricted CTL epitopes were also observed. In total, 56 amino acid differences for the complete F protein were found between the RSV A and B groups in China, while several mutations were only found in the RSV B strains during 2015-2016. The RSV F gene is relatively conserved in China, however, limited mutations are still occurring with time.

Chinese guidelines for childhood asthma 2016: Major updates, recommendations and key regional data.

OBJECTIVE: With increased industrialization and urbanization in China, pediatric asthma is becoming more prevalent. Despite a growing body of evidence, there remains a significant unmet need for adequate management of childhood asthma. The Subspecialty Group of Respiratory Diseases of the Society of Pediatrics, the Chinese Medical Association, and the editorial board of the Chinese Journal of Pediatrics have recently updated the "Guidelines for diagnosis and optimal management of asthma in children," first published in 2008. METHODS: This article reviews the major updates to the guidelines and covers the main recommendations for diagnosis, assessment, and treatment of pediatric asthma in China. Key regional data on epidemiology, clinical features, disease burden, knowledge among children and parents, and risk factors including pollution are provided to contextualize the recommendations. RESULTS: The major updates to the guidelines include: (1) A more practical definition of asthma; (2) assessment of asthma control that takes into account both current symptom control and future risk; (3) classification based on disease severity that corresponds with treatment step; (4) differentiation between difficult-to-treat and poorly controlled asthma; (5) an open-ended approach to pharmacological management; and (6) allergen immunotherapy (AIT) in mild- to moderate-persistent asthma. CONCLUSIONS: The updated "Guidelines for the diagnosis and optimal management of asthma in children (2016)" combine the latest national and international clinical evidence and experience to provide practical and reliable recommendations to Chinese clinicians.

Uncontrolled asthma and its risk factors in Chinese children: A cross-sectional observational study.

OBJECTIVE: Asthma afflicts many children in China but information about asthma management among Chinese pediatric asthma patients is limited. This study aims to evaluate asthma control among Chinese pediatric patients and identify risk factors associated with uncontrolled asthma. METHODS: A total of 4223 patients with persistent asthma aged 2-16 years from 42 tertiary hospitals across all regions of mainland China except Tibet were surveyed. Asthma Control Test (ACT), Childhood Asthma Control Test (C-ACT) and Global Initiative for Asthma (GINA) criteria were used to assess asthma control for children aged 12-16 years, 4-11 years and 2-3 years, respectively. Uncontrolled asthma was defined as ACT or C-ACT score ≤19 or GINA-defined uncontrolled asthma. Risk factors associated with uncontrolled asthma were identified using multivariate logistic regression models. RESULTS: Asthma was uncontrolled in 19.9% of the subjects. High rates of uncontrolled asthma were found in subjects with treatment non-adherence (44.1%), concomitant allergic rhinitis (AR) (23.3%), disease duration ≥ 1.5 years (22.8%), and first-degree relatives with AR (21.5%). The risk of uncontrolled asthma was much higher in the treatment non-adherence group compared to the complete adherence group (OR = 5.79, p < 0.001). Concomitant AR, disease duration ≥ 1.5 years, and first-degree relatives with AR were also confirmed as risk factors associated with uncontrolled asthma. CONCLUSIONS: About 20% of Chinese pediatric asthma patients had uncontrolled asthma. Treatment adherence and AR were the most significant risk factors. Tailored measures aimed at improving treatment adherence and diagnosis and treatment of AR should be adopted to improve the level of asthma control in Chinese children.

[Suggestions on the diagnostic criteria of childhood obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To evaluate the sleep architecture and hypoxia and clinical features of habitual snoring children with an obstructive sleep apnea-hypopnea index (OAHI) 1 to 5. METHOD: The polysomnographic data of 267 children aged from 2 to 16 years with habitual snoring were analyzed retrospectively, and the clinical features were analyzed in 108 of the children. The recruited children were divided into primary snoring group (PS group, OAHI≤1), obstructive sleep apnea hypopnea syndrome (OSAHS) group (15 or dostructive apnea index>1, LSpO2<0.92). RESULT: The oxygen desaturation index of the intermediate OSAHS group (3.8±0.4) was significantly higher than that of PS group (1.6±0.1) (χ2=34.5, P<0.01). The LSpO2 of intermediate OSAHS group was significantly lower than that of PS group (89(87,91) vs. 93(91,94), χ2=40.2, P<0.01). Comparing to the PS group, the non-rapid eye movement 1 ratio (N1%) was significantly higher (19.0±1.2 vs. 14.2±0.1, χ2=14.1, P<0.01), and the non-rapid eye movement 3 ratio (N3%) was significantly lower (24.4±1.0 vs. 29.0±1.1, P<0.01) in the intermediate OSAHS group. The pediatric questionnaire score intermediate OSAHS group was higher than PS (0.41±0.19 vs. 0.28±0.14, χ2=8.52, P=0.01). The adenoids-nasopharynx ratio was higher than that of PS group (0.70±0.07 vs. 0.62±0.10, χ2=8.96, P=0.01). The hypertrophy of tonsil was higher than PS group (2(1,2) vs. 1(1,2), χ2=7.95, P<0.05). CONCLUSION: Hypoxia and abnormal sleep structure are present in HS children with an OAHI of 1 to 5, and they also have the clinical features of OSAHS.

[Establishment and Implementation of Humanistic Nursing Care in Ophthalmic Ward].

PURPOSE: To discuss the role of humanistic nursing care in improving the nursing quality and patients' degree of satisfaction in ophthalmic ward. METHODS: A mode of humanistic nursing care was established, hospital environment was improved and work flow was arranged in details. Nurses received professional training of humanistic care skills. By using multiple educational approaches, nursing care with responsibility system can be delivered in a continuous and seamless manner. RESULTS: The measures of humanistic nursing care were fully implemented. The nurses' communication ability was improved and the nurses worked more actively. The quality of nursing and patients' degree of satisfaction (99%) were equally significantly improved. No mistake occurred and no complaint was received from the patients. CONCLUSION: Proper application of humanistic care in clinical nursing provides high-quality nursing for patients.

Nursing care of the laryngeal mask airway in pediatric cataract surgery.

PURPOSE: To investigate the important experience of nursing care of the laryngeal mask airway (LMA) in children undergoing cataract surgery. METHODS: Fifty-five children undergoing cataract surgery were anesthetized by inhaling sevoflurane through a LMA and received perioperative nursing care. The safety of perioperative nursing for these children was also evaluated. RESULTS: Through perioperative nursing care and psychological counseling for children with LMA, all patients were anesthetized without complications and underwent successful surgeries. No severe postoperative complications were observed. CONCLUSION: Nursing care specific for LMA is a vital part of the success of anesthesia and pediatric cataract surgery.

Prevention and control of perioperative incision infection in patients undergoing day cataract surgery.

PURPOSE: To explore the effects of the prevention and control of perioperative incision infection on the quality of day cataract surgery. METHODS: The nursing care and efficacy of 5087 patients undergoing day cataract surgery between October 2012 and October 2013 were retrospectively reviewed. The disinfection and isolation guidance was established for perioperative prevention and control of infection, topical administration of ocular agents, reexamination and healthcare instruction, and alternative measures were taken. RESULTS: All 5087 patients successfully underwent day surgery of phacoemulsification combined with intraocular lens implantation. All cases recovered without incision infection. CONCLUSION: Preoperative preparation, and intraoperative and postoperative prevention and control of infection serve as vital measures for effectively avoiding the incidence of incision infection in patients undergoing day cataract surgery.

Respiratory syncytial virus induces leukotriene C4 synthase expression in bronchial epithelial cells.

BACKGROUND AND OBJECTIVE: Respiratory syncytial virus (RSV) results in acute wheezing in infants and is frequently associated with recurrent wheezing. Although RSV-induced wheezing clinically resembles that of asthma, corticosteroids are not equivalently effective in RSV-associated wheezing. The study sought to determine the mechanisms of RSV-induced wheezing by establishing an in vitro model of RSV-infected human bronchial epithelial cells (16-HBEC). METHODS: Leukotriene C4 synthase (LTC4 S) messenger RNA (mRNA) expression in 16-HBEC was detected using fluorescence quantitative polymerase chain reaction, and the relative level of LTC4 S mRNA was expressed as quotient cycle threshold (qCt) based on the threshold cycle number value compared with that of ß-actin. Cysteinyl leukotrienes (CysLT) in culture supernatant were measured by enzyme-linked immunosorbent assay. RSV-infected 16-HBEC was incubated with gradient concentration of budesonide (BUD) to assess its effects on LTC4 S expression and CysLT secretion. RESULTS: RSV infection resulted in increased LTC4 S mRNA expression between 48 and 96 h post-infection. High level of CysLT was detected in the supernatant of RSV-infected 16-HBEC. BUD at concentrations of 10(-10) to 10(-5) mol/L did not significantly alter LTC4 S mRNA expression. CONCLUSIONS: RSV infection upregulated LTC4 S expression in HBEC leading to increased CysLT secretion. Such induction was not attenuated by BUD, suggesting that CysLT might contribute to the pathogenesis of RSV-induced wheezing.

Effects of nebulized high-dose budesonide on moderate-to-severe acute exacerbation of asthma in children: a randomized, double-blind, placebo-controlled study.

BACKGROUND AND OBJECTIVE: The efficacy of inhaled corticosteroids (ICS) in asthma exacerbation are yet to be clarified. The aim of this study was to investigate the efficacy of nebulized ICS in children with moderate-to-severe acute exacerbation of asthma in an emergency room setting in order to elucidate the potential use of ICS as the first-line therapy in the management of acute exacerbation of asthma. METHODS: This was a prospective, randomized, double-blind, placebo-controlled study. Paediatric patients with moderate-to-severe acute exacerbation of asthma in emergency room were randomized to receive nebulized salbutamol and ipratropium bromide, with the addition of nebulized high-dose budesonide (BUD group, n = 60) or normal saline (control group, n = 58), three doses in the first hour. RESULTS: The improvement in forced expiratory volume in 1 s was similar in both groups at 0 h after three doses of nebulization, but there was significantly further improvement at 1 and 2 h in the BUD group (0.095 ± 0.062 L and 0.100 ± 0.120 L, respectively) compared with the control group (0.059 ± 0.082 L and 0.021 ± 0.128 L, respectively), P = 0.013 and 0.001, respectively. Complete remission rate was significantly higher (84.7% vs 46.3%, P = 0.004) and need for oral corticosteroids was significantly lower (16.9% vs 46.3%, P = 0.011) in BUD group than in control group. CONCLUSION: On the basis of nebulized short-acting bronchodilators, addition of nebulized high-dose budesonide resulted in clinical improvement in children with moderate-to-severe acute exacerbation of asthma, suggesting that nebulized high-dose ICS can be used as first-line therapy for non-life-threatening acute exacerbation of asthma in children.

[The efficacy of nebulized budesonide in acute moderate to severe exacerbations of asthma in children].

OBJECTIVE: To evaluate the effect of nebulized budesonide (BUD) in acute moderate to severe exacerbations of asthma in children. METHODS: Forty children, 5 to 15 years of age, with acute moderate to severe attacks of asthma, were randomized into BUD group and control group, receiving nebulized 0.5% salbutamol (150 µg/kg) + 0.025% ipratropium bromide (1 ml) + 0.05% budesonide (2 ml) or nebulized 0.5% salbutamol (150 µg/kg) + 0.025% ipratropium bromide (1 ml) + saline (2 ml) at half-hourly intervals for 3 doses respectively. Lung function, respiratory rate (RR), heart rate(HR), oxygen saturation (SaO2) and clinical score (CS) were monitored. RESULTS: The baseline characteristics of the 2 groups were similar. After 3 doses of nebulization, CS, RR, SaO2, FEV(1) and FEV(1)% were significantly improved in both groups (P < 0.05). The CS in BUD group was significantly lower than that in control group at the end of 2 h after the third dose of nebulization 0 (0) vs 0 (1), Z = 2.522, P = 0.012. There were no significant differences in RR, HR and SaO2 between 2 groups (P > 0.05). The improvement of FEV(1)% in the first hour and the second hour after 3 doses of nebulization was 8.0 (6.8)% and 5.5 (6.5)% in BUD group, and 6.0 (8.5)% and 1.0 (6.5)% in control group, the improvement in BUD group being significantly greater than that in control group (Z = 2.270 and 2.686, P = 0.023 and 0.007 respectively). The improvement of FEV(1) in the second hour after 3 doses of nebulization was significantly greater in BUD group than in control group 0.07 (0.12) L vs 0.01 (0.10) L, Z = 2.455, P = 0.014. The full recovery rate in BUD group at the end of 2 h after completion of nebulization was significantly higher than that in control group (17/20, 85.0% vs 9/18, 50.0%, χ(2) = 5.371, P = 0.024). The proportion of patients who needed to use oral corticosteroids was significantly lower in BUD group than in control group (3/20, 15.0% vs 8/18, 44.4%, χ(2) = 3.993, P = 0.046). The hospitalization rate was 5% (1/20) in BUD group, and 17% (3/18) in control group, but the difference was not statistically significant (P > 0.05). CONCLUSION: Nebulized BUD in high dose and at short intervals combined with rapid-acting bronchodilators has an additional bronchodilator response, associated with more rapid and better improvement in clinical symptoms and lung function, indicating that it is preferred in the early management of acute moderate to severe exacerbation of asthma in children.

[Questionnaire-based survey of allergic diseases among children aged 0 - 14 years in the downtown of Beijing, Chongqing and Guangzhou].

OBJECTIVE: In recent years, the incidence of allergic diseases in China is increasing. With serious influence on the patients' quality of life and even life-threatening, now allergic diseases have become an important public health problem in our country. This survey aimed to obtain a general epidemic outline of children's major allergic diseases, i.e., childhood asthma, allergic rhinitis and eczema in the downtown of Beijing, Chongqing and Guangzhou. METHOD: Childhood asthma questionnaire was established by Delphi method based on guidelines for childhood asthma diagnosis and prevention made by Chinese medical association in 2008 with reference to the International Study of Asthma and Allergies in Childhood questionnaire (ISAAC). This study was carried out from Oct. 2008-Mar. 2009, in Beijing, Chongqing and Guangzhou by a multi-stage sampling method, covering a sample of 24 290 children aged 0 - 14 years by a multi-stage sampling method, the population of children surveyed in the downtown of Beijing Chongqing and Guangzhou was 10 372, 9874 and 4072 respectively; of whom males were 5545, 5258, 2159, and females were 4917, 4588, 1877; the ratio of males to females in the three cities were 1.11:1, 1.15:1, 1.15:1; the average age of surveyed children were 7.63, 8.74 and 8.30 years old. All the questionnaire was filled in by the parents of children or other guardian of children. RESULT: The self-reported prevalence of asthma in Beijing, Chongqing and Guangzhou was 3.15%, 7.45%, 2.09%, the self-reported prevalence of allergic rhinitis was 14.46%, 20.42%, 7.83%, and the prevalence of eczema was 20.64%, 10.02%, 7.22%. In the survey, asthma combined with allergic rhinitis had the highest rate, 49.54%, 50.14%, 34.83%, respectively in the 3 cities. The self-reported prevalence of asthma and allergic rhinitis was significantly higher in male than female. Besides, the self-reported prevalences of asthma and allergic rhinitis were relatively lower in children under 1 year and over 10 years of age. CONCLUSION: The prevalence of asthma, allergic rhinitis and eczema and other allergic diseases in children 0 - 14 years of age in the three cities gradually increased, and the prevalence of allergic diseases in Chongqing was relatively higher.

Self-reported prevalence of childhood allergic diseases in three cities of China: a multicenter study.

BACKGROUND: Several studies conducted during the 1990s indicated that childhood allergic diseases were increasing worldwide, but more recent investigations in some Western countries have suggested that the trend is stabilizing or may even be reversing. However, few data are available on the current status of allergic disease prevalence in Chinese children. The aim of the present study was to investigate the prevalence rates of asthma, allergic rhinitis, and eczema in children of three major cities of China, to determine the status of allergic diseases among Chinese children generally, and to evaluate the prevalence of allergic diseases in children of different ages. METHODS: We conducted a cross-sectional survey between October 2008 and May 2009 in three major cities of China (Beijing, Chongqing, and Guangzhou) to evaluate the prevalence rates of childhood allergic diseases including asthma, allergic rhinitis, and eczema, using a questionnaire of the International Study of Asthma and Allergies in Childhood (ISAAC) group. A total of 24,290 children aged 0-14 years were interviewed, using a multi-stage sampling method. To acquire data on children aged 3-14 years, we visited schools and kindergartens. To access children too young to attend school or kindergarten, we extended our survey to community health service centers. Each questionnaire was completed by a parent or guardian of a child after an informed consent form was signed. RESULTS: Of the 24,290 children in our study, 12,908 (53.14%) were males and 11,382 (46.86%) females; 10,372 (42.70%) were from Beijing, 9,846 (40.53%) from Chongqing, and 4,072 (16.77%) from Guangzhou. Our survey indicated that in Beijing, Chongqing, and Guangzhou, the prevalence rates of asthma were 3.15%, 7.45%, and 2.09%, respectively; the rates of allergic rhinitis were 14.46%, 20.42%, and 7.83%; and the rates of eczema were 20.64%, 10.02%, and 7.22%. The prevalence of allergic diseases varied with age. Asthma was relatively less common both in children aged under 2 years, and in those aged 9 years or more, in each of the three cities. The prevalence of allergic rhinitis was also lower in children younger than 2 years. The prevalence of eczema fell with age. CONCLUSIONS: A marked increase in the prevalence rates of allergic diseases in China (compared with earlier data) was evident. Further studies exploring the precise causes of this increase are warranted.

Current trends of the prevalence of childhood asthma in three Chinese cities: a multicenter epidemiological survey.

OBJECTIVE: To analyze the prevalence of asthma and asthma related symptoms among children aged 0-14 years in three Chinese cities and to obtain a crude estimation of the trend of childhood asthma prevalence in China. METHODS: A cross-sectional, population-based survey of prevalence of asthma was conducted in children aged from 0 to 14 years in 3 major cities of China (Beijing, Chongqing, and Guangzhou) with different geographic locations. All the subjects were randomly selected by a multi-stage sampling method. Three to five schools and kindergartens in 2 urban districts in each city were randomly selected for the survey, and a validated questionnaire that included the core questions of the International Study of Asthma and Allergies in Childhood, Phase III questionnaire and several additional questions were used. All questionnaires were completed by parents or guardians of the selected children. Children whose parents responded affirmatively to the question "Has your child ever been diagnosed as asthma by a doctor" were recognized as victims of asthma. RESULTS: The prevalence of asthma in Beijing, Chongqing, and Guangzhou was 3.15%, 7.45%, and 2.09%, respectively. These values were significantly higher than those obtained 10 years ago in the national epidemiological survey in 2000 which used the same method of investigation and the same diagnotic criteria (χ²=3.938, P=0.047; χ²=73.506, P≤0.001; χ²=11.956, P=0.001, in each city). Of the asthmatic children 57.21%, 69.91%, and 60.00% had their first attack before the age of 3 in Beijing, Chongqing, and Guangzhou, respectively. Wheezing was the primary clinical manifestation for all asthmatic children, followed by persistent cough and repeated respiratory infections. Both the prevalence of asthma and asthma-related symptoms were statistically higher in males than in females. CONCLUSION: The prevalence of childhood asthma is statistically higher than that 10 years ago in the three Chinese cities.