Epidemiological trends for human schistosomiasis prevalence in Hubei Province from 2004 to 2018 based on Joinpoint regression analysis / 中国血吸虫病防治杂志

Objective To analyze the trends of human schistosomiasis prevalence in Hubei Province from 2004 to 2018, so as to provide the evidence for formulating the schistosomiasis elimination strategy in the province. Methods All data pertaining to human schistosomiasis prevalence in Hubei Province were collected from 2004 to 2018, and the trends for changes in seroprevalence, egg-positive rate and prevalence of human Schistosoma japonicum infection were analyzed using a Joinpoint regression model. Results Both of the numbers of residents seropositive and egg-positive for S. japonicum infections appeared a tendency towards a decline in Hubei Province from 2004 to 2018, and the prevalence of human S. japonicum infections reduced from 6.85% in 2004 to 0 in 2018. Joinpoint regression analysis showed that the prevalence of human S. japonicum infections appeared an overall tendency towards a reduction in Hubei Province from 2004 to 2018 [average annual percent change (AAPC) = −24.1%, P < 0.01], and the trends for the reduction were both significant during the period from 2004 to 2006 [annual percent change (APC) = −35.1%, P < 0.01] and from 2006 to 2018 (APC = −22.1%, P < 0.01). The prevalence of human S. japonicum infections appeared a tendency towards a decline in islet (AAPC = −25.1%, P < 0.01), inner embankment (AAPC = −26.4%, P < 0.01) and hilly subtypes of schistosomiasis-endemic areas (AAPC = −32.5%, P < 0.01) of Hubei Province from 2004 to 2018, and the prevalence all appeared a tendency towards a decline during the infection control stage (from 2004 to 2008), the transmission control stage (from 2009 to 2013) and the transmission interruption stage (from 2014 to 2018) (AAPC = −28.0%, −24.4% and −63.8%, all P values < 0.01). The seroprevalence of human S. japonicum infections appeared an overall tendency towards a decline in Hubei Province from 2004 to 2018 (AAPC = −14.5%, P < 0.01), and the trends for the reduction were both significant during the period from 2004 to 2012 (APC = −8.4%, P < 0.01) and from 2012 to 2018 (APC = −22.1%, P < 0.01). In addition, the egg-positive rate of human S. japonicum infections appeared an overall tendency towards a decline in Hubei Province from 2004 to 2018 (AAPC = −30.6%, P < 0.05), and the trend for the reduction was significant during the period from 2007 to 2014 (APC = −15.5%, P < 0.01). Conclusions The prevalence of human schistosomiasis appeared a tendency towards a decline in Hubei Province from 2004 to 2018, and the islet and inner embankment subtypes of endemic areas are a high priority for schistosomiasis control during the stage moving towards elimination in Hubei Province.

[Current Status of and Challenges in Diagnosis and Treatment of Childhood Diffuse Parenchymal Lung Diseases/Childhood Interstitial Lung Diseases].

The medical field in China has witnessed encouraging progress in specialized theoretical research and clinical practice concerning childhood diffuse parenchymal lung diseases/childhood interstitial lung diseases (chDPLD/chILD) after many years of hard work. However, we have also encountered many tasks and challenges. We must approach the problem with a holistic perspective, and collect, accumulate and analyze, in a uniform way, the data from all over the country. We should try our best to obtain more pathological materials for further analysis of the diagnosis and treatment as well as clinical research. The diagnosis protocol and treatment recommendations should be revised regularly. Moreover, we emphasize the adoption of the clinico-radio-genetic-pathological (C-R-G-P) management model and the multi-disciplinary team (MDT) approach to the diagnosis and treatment of chDPLD/chILD. In this way, we will be able to improve our cognitive understanding and enrich our experience in the prevention and management of chDPLD/chILD further more.

Establishment of an indicator system for schistosomiasis transmission risk assessment after transmission interruption in Hubei Province based on the Delphi method / 中国血吸虫病防治杂志

Objective To establish an indicator system for assessment of schistosomiasis transmission risk after transmission interruption in Hubei Province, so as to provide insights into the precise control of schistosomiasis. Methods The indicator system was preliminarily established based on data collection, literature review, expert interviews. Two rounds of expert consultation were performed. The indicator system was screened based on the importance, operability, sensitivity and comprehensive score of the indicators, and the weights of each indicator were calculated. The credibility of the Delphi method was evaluated by calculating the active coefficient of the experts, degree of expert authority and coordination levels of experts’ opinions. Results An indicator system for assessment of schistosomiasis transmission risk was preliminarily established, including 3 primary indicators, 12 secondary indicators and 44 tertiary indicators. A Delphi consultation was performed among 17 experts participating in schistosomiasis control, management and research. Following two rounds of consultation, a risk assessment indicator system was finally constructed, including 3 primary indicators, 10 secondary indicators and 35 tertiary indicators. Among the primary indicators, the variable with the highest normalized weight was the current status of schistosomiasis (0.420 2), followed by social factors (0.397 3) and natural environments (0.182 5). Among the secondary indicators, those with high combined weights included risk monitoring (0.142 3), current snail status (0.140 1), and current prevalence of human and livestock infections (0.137 8). Among the tertiary indicators, those with high combined weights included the positive rate of wild feces (0.049 8), the prevalence of snail infections (0.047 4), and the area of snail habitats submerged by floods (0.046 8). During the two-round consultation, the active coefficients of the experts were 85.00% and 100.00%, the degree of expert authority was both 0.75 and greater, and the coordination levels of experts’ opinions were 0.405 to 0.521 and 0.592 to 0.695 (all P values < 0.05). Conclusion An indicator system for assessment of schistosomiasis transmission risk is successfully established after transmission interruption in Hubei Province based on the Delphi method, which provides insights into the identification of the schistosomiasis transmission risk and the targets for schistosomiasis control in Hubei Province.

Survey of snail distribution in Four-lake Basin of Hubei Province / 中国血吸虫病防治杂志

Objective To investigate the distribution of Oncomelania snails in Four-Lake Basin of Hubei Province, so as to provide scientific evidence for the development of snail control interventions. Methods The snail distribution was surveyed by means of the retrospective study and cross-sectional survey in the Four-Lake Basin in Spring of 2016. The data pertaining to the endemic situation of schistosomiasis were collected and analyzed in the Four-Lake Basin from 2008 to 2018, and the associations of snail habitat areas with the prevalence of Schistosoma japonicum in humans and bovines were examined. Results There were 16 003 snail habitats in the 9 schistosomiasis-endemic counties (districts) in the Four-Lake Basin in 2016, covering an area of 246 million m2. The mean density of living snails was 0.622 5 snails/0.1 m2, which was relatively high in weed-type settings (0.688 0 snails/0.1 m2) and ditches (0.706 4 snails/0.1 m2). Type I (current snail habitats, 53.03%) and Ⅱ- Ⅳ (historical snail habitats, 46.97%) settings were predominant snail habitats. A big change was seen in snail habitats in dry farmland, marshland and paddy farmland, and environmental modification resulted in satisfactory snail control effectiveness. In addition, the area of snail habitats positively correlated with the changes in the prevalence of S. japonicum infections in humans (r = 0.842, P < 0.01) and livestock (r = 0.695, P < 0.01). Conclusions The integrate strategy with an emphasis on the control of the source of S. japonicum infections results in remarkable snail control effectiveness in the Four-Lake Basin; however, there is a risk of re-emerging snail habitats.

[Administrative village-based spatial distribution specificity of Oncomelania hupensis and its relationship with water systems in Hubei Province].

OBJECTIVE: To investigate the spatial distribution of Oncomelania hupensis snail habitats at the administrative village scale in schistosomiasis-endemic areas of Hubei Province, so as to provide scientific bases for precise control of O. hupensis snails in the province. METHODS: Data regarding snail distribution at the village level in Hubei Province in 2017 were collected to create a spatial analysis database of snail distribution in Hubei Province. The spatial aggregations of O. hupensis distribution were analyzed using Moran's I index and Local Moran's I index. In addition, the distances from schistosomiasis-endemic villages to the Yangtze River were captured using the software ArcGIS 13.0, and their correlations with area of snail habitats were examined with the Spearman correlation method. RESULTS: O. hupensis snails were mainly distributed in 5 450 endemic villages from 63 counties of 13 cities in Hubei Province in 2017. The global spatial autocorrelation analysis showed spatial aggregations in the areas of historically accumulated snail habitats, current areas of snail habitats, areas of snail habitats outside the embankment and snail habitats inside the embankment (all Z Scores > 0, all P values < 0.05), and no spatial aggregation was seen in the areas of snail habitats in hilly areas (Z Score > 0, P > 0.05). There were four types of spatial distribution of historically accumulated areas of snail habitats, areas of current snail habitats, areas of snail habitats outside the embankment and snail habitats inside the embankment, including the high-high type (H-H type), high-low type (H-L type), low-high type (L-H type) and random distribution type, and a high percentage of the H-H type was found. There were 340, 125 and 110 endemic villages with the H-H type of areas of historically accumulated snail habitats, current areas of snail habitats and areas of snail habitats outside the embankment, and these villages were mainly concentrated in Wuhan and Jingzhou cities, with almost consistent spatial aggregation locations. There were 319 endemic villages with the H-H type of distribution of snail habitats inside the embankment, which were mainly distributed in Jingzhou, Xiaogan and Huangshi cities. In addition, the areas of historically accumulated snail habitats, current areas of snail habitats and areas of snail habitats outside the embankment negatively correlated with the distance from the endemic villages to the Yangtze River (r = -0.094, P < 0.01; r = -0.225, P < 0.01; r = -0.177, P < 0.01). CONCLUSIONS: The clustering areas of snail habitats along the Yangtze River Basin, notably the villages near the Yangtze River are key regions for snail monitoring and control in Hubei Province.

Three-dimensional analysis of the physiologic drift of adjacent teeth following maxillary first premolar extractions.

We assessed the three-dimensional (3D) pattern of the physiologic drift of the remaining adjacent teeth after premolar extraction due to orthodontic reasons and the associated factors. Data were collected from 45 patients aged 17.04 ± 5.14 years who were scheduled to receive a fixed appliance after maxillary premolar extraction. Seventy-five drift models were obtained and digitalized via 3D scanning. The average physiologic drift duration was 81.66 ± 70.03 days. Angular and linear changes in the first molars, second premolars, and canines were measured using the 3D method. All the examined teeth had tipped and moved towards the extraction space, leading to space decreases. Posterior teeth primarily exhibited significant mesial tipping and displacement, without rotation or vertical changes. All canine variables changed, including distal inward rotation and extrusion. The physiologic drift tended to slow over time. Age had a limited negative effect on the mesial drift of posterior teeth, whereas crowding had a limited positive effect on canine drift. Thus, the mesial drift of molars after premolar extraction may lead to molar anchorage loss, particularly among younger patients. The pattern of the physiologic drift of maxillary canines can help relieve crowding and facilitate labially ectopic canine alignment, whereas canine drift is accelerated by more severe crowding.

Administrative village-based spatial distribution specificity of Oncomelania hupensis and its relationship with water systems in Hubei Province / 中国血吸虫病防治杂志

Objective To investigate the spatial distribution of Oncomelania hupensis snail habitats at the administrative village scale in schistosomiasis-endemic areas of Hubei Province, so as to provide scientific bases for precise control of O. hupensis snails in the province. Methods Data regarding snail distribution at the village level in Hubei Province in 2017 were collected to create a spatial analysis database of snail distribution in Hubei Province. The spatial aggregations of O. hupensis distribution were analyzed using Moran’s I index and Local Moran’s I index. In addition, the distances from schistosomiasis-endemic villages to the Yangtze River were captured using the software ArcGIS 13.0, and their correlations with area of snail habitats were examined with the Spearman correlation method. Results O. hupensis snails were mainly distributed in 5 450 endemic villages from 63 counties of 13 cities in Hubei Province in 2017. The global spatial autocorrelation analysis showed spatial aggregations in the areas of historically accumulated snail habitats, current areas of snail habitats, areas of snail habitats outside the embankment and snail habitats inside the embankment (all Z Scores > 0, all P values < 0.05), and no spatial aggregation was seen in the areas of snail habitats in hilly areas (Z Score > 0, P > 0.05). There were four types of spatial distribution of historically accumulated areas of snail habitats, areas of current snail habitats, areas of snail habitats outside the embankment and snail habitats inside the embankment, including the high-high type (H-H type), high-low type (H-L type), low-high type (L-H type) and random distribution type, and a high percentage of the H-H type was found. There were 340, 125 and 110 endemic villages with the H-H type of areas of historically accumulated snail habitats, current areas of snail habitats and areas of snail habitats outside the embankment, and these villages were mainly concentrated in Wuhan and Jingzhou cities, with almost consistent spatial aggregation locations. There were 319 endemic villages with the H-H type of distribution of snail habitats inside the embankment, which were mainly distributed in Jingzhou, Xiaogan and Huangshi cities. In addition, the areas of historically accumulated snail habitats, current areas of snail habitats and areas of snail habitats outside the embankment negatively correlated with the distance from the endemic villages to the Yangtze River (r = −0.094, P < 0.01; r = −0.225, P < 0.01; r = −0.177, P < 0.01). Conclusion The clustering areas of snail habitats along the Yangtze River Basin, notably the villages near the Yangtze River are key regions for snail monitoring and control in Hubei Province.

Effects of nicotine on proliferation and survival in human umbilical cord mesenchymal stem cells.

Cigarette smoking is known to have negative effects on tissue repair and healing. The aim of this study is to investigate the effects of nicotine in human umbilical cord mesenchymal stem cells (MSCs). After nicotine treatment, MSCs became pyknotic, vacuoles appeared in the cytoplasm and nucleus, and the nuclear boundary became fuzzy as observed using atomic force microscopy. Cell proliferation was inhibited in a dose-dependent manner (P < 0.05 for all concentrations). The proportion of apoptotic MSCs was significantly increased in a dose-dependent manner. The mitochondrial membrane potential was significantly decreased (P < 0.05). Nicotine-treated MSCs had a significantly higher G0/G1 ratio (P < 0.05). Peptide mass fingerprinting identified 27 proteins that were differentially expressed between MSCs with and without nicotine treatment. These nicotine exerted toxic effects on MSCs are likely related, at least in part, to the altered expression of multiple proteins that are essential to the health and proliferation of these cells.

[Chest CT features and outcome of necrotizing pneumonia caused by Mycoplasma pneumoniae in children (report of 30 cases)].

OBJECTIVE: To summarize the chest CT features and outcome of necrotizing pneumonia (NP) caused by Mycoplasma pneumoniae in children and to review the changes of common inflammatory parameters in NP patients to help clinicians understand the proper timing of CT scan. METHOD: The imaging data from 30 cases of Mycoplasma pneumoniae pneumonia in NP group and 24 cases with non-necrotizing Mycoplasma penumoniae pneumonia (control group) were analyzed retrospectively. The changes of common inflammatory parameters in NP group and control group were compared. RESULT: (1) The chest CT findings of NP (30 cases): 28 cases showed unilateral pneumonia, and 20 cases showed single lobar consolidation, 10 cases had multiple lobes involvement; pulmonary cavities were seen in 27 cases. There were decreased enhancement areas in the consolidation (22 cases). (2) The dynamic changes of CT signs during follow-up: The CT scan performed during the 1 - 2 months after onset of disease (23 cases) showed that pulmonary consolidation in 2 cases (9%) were absorbed, 18 cases (78%)had cavities in lung, 16 cases (70%) had pleural thickening, 2 cases (9%) atelectasis and 1 case (4%) bronchopleural fistula;the CT scan performed during the 2 - 3 months after onset of disease (11 cases) showed pulmonary consolidation in 7 cases (64%) were absorbed, 10 cases (91%) pleural thickness, 7 cases (64%) with cavities in lung, 5 cases (45%) atelectasis, 2 cases (18%) pulmonary lobe cysts and 1 case bronchopleural fistula. The CT scan performed at 3.5 years of disease course (10 cases) showed that there were no pulmonary consolidation in any of the cases, 4 cases had atelectasis, 4 cases had pulmonary cysts, and 1 case had band-like scars. (3) There were significant differences between NP group and control group in the maximum peripheral blood WBC, proportion of neutrophil and C-reactive protein(CRP, mg/L) (P < 0.01, 0.01, 0.001, respectively), and there was significant difference between the 2 groups in the duration of fever, abnormal WBC(d) and CRP(d) (P < 0.001). CONCLUSION: The chest CT features of NP caused by Mycoplasma pneumoniae in children were single lobular consolidation in most cases, NP had decreased parenchymal enhancement and cavity in the consolidation, and recovery was slow, the outcome included recovery, atelectasis or lobar cystic degeneration. The clinicians should pay more attention to the common inflammatory parameters when they suspect the Mycoplasma pneumoniae pneumonia is progressing into necrosis and make correct decision for chest CT examination.

[Pulmonary surfactant protein gene mutation associated with pediatric interstitial lung disease: a case study and the review of related literature].

OBJECTIVE: To report a case of pulmonary surfactant protein (SP) gene mutation associated with pediatric interstitial lung disease, and study the clinical diagnosis process and review of related literature, to understand the relationship between interstitial lung disease and SP gene mutation in infants and children. METHOD: The clinical, radiological, histological, and genetic testing information of a case of SP gene mutation related pediatric interstitial lung disease were analyzed and related literature was reviewed. RESULT: A 2-year-old girl without a history of serious illness was hospitalized because of the shortness of breath, cough, excessive sputum, and the progressive dyspnea. Physical examination on admission revealed tachypnea, slight cyanosis, and the retraction signs were positive, respiratory rate of 60 times/minute, fine crackles could be heard through the lower lobe of both lungs; heart rate was 132 beats/minute. No other abnormalities were noted, no clubbing was found. Laboratory test results: pathologic examination was negative, multiple blood gas analysis suggested hypoxemia. Chest CT showed ground-glass like opacity, diffused patchy infiltration. Bronchoalveolar lavage fluid had a large number of neutrophils, and a few tissue cells. Eosinophil staining: negative. Fluconazole and methylprednisolone were given after admission, pulmonary symptoms and signs did not improve, reexamination showed no change in chest CT. Then lung biopsy was carried out through thoracoscopy. Histopathology suggested chronic interstitial pneumonia with fibrosis. The heterozygous mutation of R219W in the SFPTA1 and the S186N in SFTPC were identified by SP-related gene sequencing. The review of related literature showed that polymorphisms at the 219th amino acid in SP-A1 allele were found in adults with idiopathic pulmonary fibrosis (IPF), but there is no related literature in pediatric cases. The patient in this report had a mutation at the SP-A1 allele consistent with related literature. Data of 17 young children with mutation in SP-C gene showed that all the 17 cases had dyspnea and tachypnea, chest CT revealed diffuse opacities in lungs, the pathology of lungs was NSIP and CPI. There were 17 kinds of mutation and the common mutation was I73T. The mutation of S186N in SFTPC in our case has never been shown in previously published literature. CONCLUSION: A case of interstitial lung disease with S186N gene mutation in SFTPC was preliminarily diagnosed in an infant. The SP-C gene mutations and polymorphisms are associated with pediatric interstitial lung disease.

[Chest radiographic findings in children with 2009 influenza A (H1N1) virus infection].

OBJECTIVE: To evaluate chest radiographic findings of children with 2009 influenza (H1N1) virus infection. METHOD: Data of 235 patients who had microbiologically confirmed H1N1 infection and available chest radiograph obtained between May 1(st) 2009 and Jan. 31(st) 2010 were retrospectively analyzed. The final study group was divided on the basis of clinical course [group 1 mild, outpatients without hospitalization (n = 172); group 2 moderate, inpatients with brief hospitalization (n = 49); group 3 severe, ICU admission (n = 14)]. Four pediatric radiologists reviewed all the chest radiographs of lung parenchyma, airway, pleural abnormalities and also anatomic distribution of the disease. RESULT: No significant sex or age differences were found among the study groups (P > 0.05). The mean interval between the onset of clinical symptom and the initial chest radiography was (5.91 ± 1.64) days (group 1), (3.60 ± 1.43) days (group 2) and (1.21 ± 0.41) days (group 3), respectively. The differences among the three groups were significant statistically (χ(2) = 13.368, P < 0.01). The ratio of abnormality presented at initial chest X-ray was 79.7% in group 1, 91.8% in group 2 and 100% in group 3. Radiographically, there were prominent peribronchial markings (group 1, 55.2%; group 2, 83.7%; and group 3, 78.6%), consolidation (group 1, 34.3%; group 2, 69.4%; and group 3, 100.0%), hyperinflation (group 1, 22.1%; group 2, 44.9%; and group 3, 50.0%) and ground glass opacity (group 1, 0.6%; group 2, 2.0%; and group 3, 14.3%) in the chest radiographs. The differences of presenting were statistically significant (P < 0.01). In the severe group, the lesions distributed diffusely and asymmetrically with multi-lobe involvements. CONCLUSION: In children with 2009 influenza A H1N1 viral infection, the interval between the onset of clinical symptom and initial chest radiography, the ratio of abnormality presented at initial chest X-ray film and the severity of chest film are parallel to their clinical situation.

[Clinical study on interstitial lung disease in children of China].

OBJECTIVE: Interstitial lung disease in children represents a heterogeneous group of disorders of both known and unknown causes. This study aimed to understand better the causes of the disease in children and to provide information on the current approach to diagnosis and management of the disease. METHOD: Through the Pediatric Diffuse Parenchymal Lung Disease/Pediatric Interstitial Lung Disease Cooperative Group of China, data of 93 cases of interstitial lung disease of children from 11 hospitals were collected with the same questionnaire in 2009. Respiratory tract secretions were obtained for bacterial culture. Respiratory virus antigen examination, mycoplasma antibody, EB virus, cytomegalovirus, and herpes simplex viruses antibody detection were performed. Cells in the sputum, gastric juice and bronchoalveolar lavage fluid (BALF) were tested for hemosiderin. The CT or high resolution CT (HRCT) of the lung and blood-gas analysis were also performed. Fourteen cases underwent lung biopsy and 25 cases underwent bronchomicrocopy. Data were then pooled and discussed through a series of meetings. RESULT: Fifty-three cases were male, 40 were female and their age ranged from 8 months to 14 years. Thirty-nine cases were diagnosed as bronchiolitis obliterans (BO); 39 as idiopathic pulmonary hemosiderosis (IPH); 7 as idiopathic interstitial pneumonia (IIP) of unknown causes, of whom 4 cases had non specific interstitial pneumonia, 1 case as acute interstitial pneumonia and 1 case as lymphocytic interstitial pneumonia, 1 case as idiopathic pulmonary fibrosis; 2 cases as secondary interstitial lung disease, one was secondary to SLE, one to human immunodeficiency virus (HIV) infection; 2 cases had hypersensitive pneumonitis; 2 cases had pulmonary alveolar proteinosis; 1 case had bronchiolitis obliterans organizing pneumonia; 1 case had lipoid pneumonia;1 case of diffuse panbronchiolitis; 1 case of microlithiasis alveolaris pulmonum. Forty two cases had cough, 24 of them also had tachypnea, 8 cases had clubbing. HRCT showed that 56 cases had groundglass-like opacification; 30 cases had mosaic appearance; 1 case had diffuse micronodular opacities, 1 case had diffuse reticulonodular opacities and cysts. CONCLUSION: Interstitial lung disease in children is a heterogeneous group of disorders. In this study diagnoses of 11 diseases were made, the top third diagnoses were BO, IPH and IIP, respectively.

[Analysis of clinical manifestations of 159 hospitalized children infected with 2009 novel influenza A (H1N1) virus].

OBJECTIVE: To analyze the clinical characteristics of hospitalized pediatric patients infected with 2009 H1N1 influenza. METHODS: Totally 159 children (83 male and 76 female) with influenza A (H1N1) confirmed by the real-time reverse-transcriptase-polymerase-chain-reaction assay were admitted to a special ward of Capital Institute of Pediatrics from November 2009 to January 2010. Clinical manifestations, laboratory and therapy data from the hospitalized children were collected by designed case report form and analyzed. RESULTS: Out of 159 hospitalized patients, 139 (87.4%) were under the age of 5 years and 34.0% of them had at least one underlying medical conditions. Proportions of the severe cases, pneumonia and underlying medical diseases were similar between the 78 infants and 81 older children. All of these 159 cases had influenza-like symptoms at onset and the most common presentations were fever (115 cases, 72.3%) and cough (154 cases, 96.8%). Five severe cases presented dyspnea, cyanosis and hypoxemia. The virus easily invaded into the lower respiratory tract as indicated by that 61% of the cases had findings consistent with pneumonia by X-ray and/or CT and 21.6% had bacterial co-infection. Part of them had mycoplasma pneumonia (20 cases, 27.0%) or other respiratory viruses (5 cases, 3.1%) co-infection simultaneously. The duration of fever was similar between the H1N1 virus sole infection group and the co-infection group (t = 0.975, P > 0.05), but the average course of the disease and hospitalized days of the latter group were longer than the former (t = 3.182 and 3.190, P < 0.01). The proportion of children with pneumonia in the co-infection group was significantly higher than that in the H1N1 sole-infection group (χ(2) = 4.082, P < 0.05). CONCLUSIONS: Most of the H1N1 infected pediatric patients had mild respiratory symptoms, a few of them developed severe manifestations. Dyspnea and hypoxemia were the early signals for the developing severe cases. Rational and experienced treatment with antibiotics was important addition to the antiviral therapy for those co-infected with bacteria.