Epidemiological Characteristics And Clinical Research Of Human Parainfluenza Virus 3 Pneumonia In Hospitalized Children In Suzhou Area

ObjectivesTo investigate the epidemic characteristics of human parainfluenza virus 3 pneumonia in hospitalized children and its relationship of meteorological factors in suzhou,and to explore the clinical characteristics of HPIV3 pneumonia.Methods7525 cases of children hospitalized with community-acquired pneumonia(community-acquired Pneumonia,CAP)were obtained from January 2014 to December 2017 in the Department of Respiration,Children's Hospital Affiliated Soochow University.The method of sterile negative pressure suction was used to collect nasopharyngeal secretions.Including sputum culture for bacteria;direct immunofluorescence detection of 7 kinds of common respiratory viruses including human parainfluenza virus 1,2,3(HPIV1,2,3),respiratory syncytial virus(RSV),adenovirus(ADV),influenza virus A and B(InfA,B);reverse transcription polymerase chain reaction(RT-PCR)for the human metapneumovirus(hMPV)and human respiratory rhinovirs(HRV);real-time fluorescentPCR for the human bocavirus virus(HBoV),mycoplasma pneumoniae(MP).Meanwhile,some meteorological data were collected such as monthly average temperature(?),monthly mean humidity(%),monthly precipitation(mm),monthly total sunshine time(h),monthly mean wind speed(m/h)etc.from January 2014 to December 2017 in Suzhou area.Collect the clinical date of the children hospitalized with HPIV3 pneumonia,analyse the clinical features between the single-pathogen infection and multi-pathogen coinfection,and compare the the clinical features with RSV pneumonia,then the relationship between the detection of HPIV3 pneumonia and metrorological factors was analyzed by spearman correlation coefficient and stepwise regression analysis.Results1.2458 cases(32.66%)of virus were positive among 7525 cases.The cases of respiratory syncytial virus(RSV)were 856(11.38%),human rhinovirus(HRV)903(12.00%),human parainfluenza virus 3(HPIV3)268(3.56%),human bocavirus(HBoV)251(3.34%),human metapneumonia virus(hMPV)19(0.25%),adenovirus(ADV)57(0.76%),influenza virus A(InfA)55(0.73%),influenza B(InfB)24(0.32%),human parainfluenza virus 1(HPIV1)20(0.27%)and human parainfluenza virus 2(HPIV2)5(0.07%).The top three detected virus were HRV,RSV and HPIV3.2.The positive rates were respectively 4.20%,5.87%,3.80%,1.24%and 0.62%among the children who were less than 6 months,6 to 12 months,1 to 3 years old,3 to 5 years old and more than or equal to 5 years old.The group of 6-12 month age had the highest detection rate.There was a significant difference in the detection rate between different age groups(x2=58.322,P<0.001),and less than 6 months group of children with higher detection rate than 3 to 5 years old,more than or equal to 5 years old(x2=20.315,24.187,P<0.05),6 to 12 months group of children with higher detection rate than 1 to 3 years old,3 to 5 years old and more than or equal to 5 years old(x2=20.315,33.601,36.465,P<0.05).3.The annual detection rate of HPIV3 pneumonia in 2014 to 2017 were 3.25%,3.06%,4.24%,and 3.75%respectively.There was no significant difference in the detection rate of HPIV3 between the four years(x2=4.611,P>0.05).4.The detection rate of HPIV3 pneumonia was 5.45%in spring,6.47%in summer,1.79%in autumn,0.73%in winter,which was statistically significant in different seasons(x2=127.01,P<0.001).Positivity rate of spring and summer was higher than that of autumn and winter.Positivity rate of summer was higher than that of spring(x2=1.70,P>0.05).Positivity rate of summer was higher than that of autumn and winter(x2=52.11,91.20,P<0.001).Positivity rate of spring was higher than that of autumn and winter(x2=36.44,71.78,P<0.001).Positivity rate of autumn was higher than that of winter.(x2=8.749,P<0.05).5.Among 268 cases of HPIV3 pneumonia children,the main clinical manifestations were cough(98.13%),wheezing(38.06%),fever(46.64%),stuffiness and/or runny nose(40.67%),shortness of breath(6.72%),dyspnea(2.24%),wheezing and/or phlegm(74.25%),chest radiograph abnormalities(95.90%).There are 7 cases of severe HPIV3 pneumonia(2.61%).6.96 cases of HPIV3 pneumonia children had mixed infection,the top three of which including 26 cases of HPIV3+HRV(9.70%),26 cases of HPIV3+MP(9.70%),23 cases of HPIV3+SP(8.58%).7.HPIV3 pneumonia occurred frequently in 6-12 months old,high in spring and summer,and RSV pneumonia in 0-6 months old,high in autumn and winter,they are different in clinical manifestations,high fever(24.63%vs 10.05%,P<0.001)in children with HPIV3 is more common,while wheezing(38.06%vs 62.73%,P<0.001),shortness of breath(6.72%vs 15.54%,P<0.001),and severe pneumonia(2.61%vs 12.15%,P<0.001)is more common in children with RSV pneumonia.8.The detection rate of HPIV3 had highly positive correlation with monthly mean temperature?total rainfall.(r=0.676,0.526,<0.001),moderate correlation with monthly wind speed.(r=0.431,P=0.002).Conclusions1·HPIV3 is one of the most important pathogens of community-acquired pneumonia among hospitalized children in Suzhou area.The group of 6-12 month age had the highest detection rate.2.Co-infection was common in patients with HPIV3 pneumonia.The common pathogen co-infected was HRV,MP and SP.3.The clinical manifestations of HPIV3 pneumonia has no obvious specific characteristics compared with other respiratory virus pneumonia.HPIV3 pneumonia and RSV pneumonia are different in age,season and clinical symptoms.4.The prevalence of HPIV3 pneumonia was higher during spring and summer.The positive rate of HPIN3 has highly positive correlation with monthly mean temperature and total rainfall,and moderate correlation with monthly wind speed.