The Study Of Etiology Of Acute Respiratory Infection In Children And Climate-related In Suzhou

Object Jointly monitoring and analyzing epidemiology and clinical characteristics of the bacteria, viruses, Mycoplasma pneumoniae and many pathogenic in children with acute respiratory infection four years in Suzhou; Exploring the relationship between pathogen and meteorological factors.Methods From Oct 2005 to Sep 2009, 8172 hospitalized children with ARI were chosen, of which 6599 cases were collected fresh sputum using sterile suction method, All specimens were detected seven common viruses'antigen and hMPV gene using direct immunofluorescence and RT-PCR, 6404 specimens were cultured for bacteria; of which 7842 cases were collected venous blood 2ml of the day, and of which 2976 cases were collected the second serum 5 to 7 days after admission, the specimens using ELISA for quantitative detection of MP-IgG/IgM. Then analyzed and studyed the positive cases in four methods after collect and collate. To Suzhou weather station to negotiate and obtain the meteorological data, To further explore the relationship between a variety of pathogenic and the climate.Results The positive specimens of one or more pathogens detected was 4756(58.2%) in 8172 cases, the positive was 1883(29.4%) in 6404 bacterial detection specimens, the positive was 1886(28.2%) in 6599 virus detection specimens, the positive was 2630(33.5%) in 7842 MP detection specimens. Total pathogens, bacteria and MP detection rate were increased year by year, the peak of virus detection rate was appear in the following year. The top four of bacterial detection rate is SP(10.8%), HI(4.8%), SA(4.7%), MC(3.4%), the top four of virus detection rate is RSV(15.8%), hMPV(8.3%), PIV-3(2.1%), IVA (2.0%). Pathogen mixed infection rate was 16.9%, mixed infection with bacteria is the most common, followed by virus, MP at least, the form of infection with bacteria+virus is the most common, in all pathogens MP+SP, MP+RSV, SP+RSV were more common. In terms of age and gender distribution, detection rate of 30d～1y and 3～5y group were higher for the bacteria, the younger the higher for the virus, the older the higher for the MP. detection rate of 30d～1y group were highest for the SP, HI, SA, and MC, the younger the higher for the RSV, it was higher in 3～5y, 30d～1y, 1～3y group, respectively, for the hMPV, PIV-3 and IVA, detection rate of female children was higher than male for the HI, PIV-1and MP, other pathogens no gender differences. In terms of seasonal distribution, detection rate of bacteria was lowest in autumn, no difference between the other three seasons, detection rate of virus was higher in winter and spring, lower in summer and autumn, detection rate of MP was higher in summer and autumn, lower in winter and spring(p<0.0001). detection rate of SP, MC in the winter, HI in the spring and summer were higher, RSV in winter was highest, followed by the spring and lowest in summer (p<0.0001). hMPV in winter and spring, PIV-3 in summer were higher, IVA in summer was lower, the other three seasons was no difference, detection rate of SA, PIV-1 and PIV-2 was not significantly different in seasonal distribution. In terms of disease distribution, bacteria easily cause bronchial pneumonia and severe pneumonia, virus easily cause bronchiolitis, MP easily cause URI, asthma attacks, lobar pneumonia and interstitial pneumonia. Pathogen and climate-related analysis showed: The impact of bacterial infection affected by meteorological factors was not obvious, virus infection with temperature, rainfall and sunshine duration was negatively correlated (temperature>sunshine>rainfall), sometimes also there was short- term negative impact of wind speed and humidity, MP infection with temperature and rainfall was positively correlated (temperature>rainfall), with the sunshine was less correlation, but sometimes the impact of sunshine will exceed rainfall, wind speed also has short-term positive effects. HI with wind speed, SA with humidity was positively correlated, MC with temperature was negatively correlated, RSV with five kinds of meteorological factors was negatively correlated (temperature>wind>rainfall >sunshine>humidity), hMPV with temperature was negatively correlated, sometimes also affected by the negative effects of rainfall and sunshine. PIV-3 infection with temperature and rainfall were positively correlated (rainfall>temperature). ADV with humidity was negatively correlated. IVA and meteorological factors was no significant correlation, however, sometimes rate of infection was higher in the cold, heat, more or less sunlight. From the view of the impact of climate on disease, temperature, rainfall, sunshine on the URI, as well as rainfall, sunshine on the LRI was no significant effect, incidence of the LRI was higher in the temperature 10℃～25℃. Bacterial URI at little rain and bacterial LRI in the temperature 10℃～25℃have a higher prevalence,virus URI at low temperature and less sunshine have a higher prevalence, virus LRI at low temperatures, little rain and high sunshine hours have a higher prevalence, LRI of the MP in wet, high sunlight and temperatures above 10℃have a higher prevalence.Conclusion MP is the most common important pathogen of children ARI in local area, followed by viruses, bacteria was the common in mixed infections and severe infections. The most common four pathogens of bacteria and virus are SP, HI, SA, MC and RSV, hMPV, PIV-3, respectively. was significant, bacteria infection are not relatively obvious. The incidence was increased significantly when MP increased with age, the virus decreased with age; The incidence was higher when MP in the summer and autumn high temperature, rainfall, high sunshine hours, the virus in the winter and spring low temperatures, drier, less sunshine. Age, seasonal distribution of bacteria and relationship with climate was not significant. In all pathogens, the effect of RSV affected by meteorological factors was most significant, followed by MP, and then followed that hMPV, PIV-3, ADV, and IVA. Bacterial URI at little rain, bacterial LRI in the temperature 10℃～25℃,viral URI in the winter, viral LRI in the winter high sunshine, LRI of the MP outside the winter have a higher prevalence.