Objective To study human bocavirus (HBoV) induced respiratory tract infection in Guangdong Province in China. Methods HBoV was deteced by using polymerase chain reaction (PCR) technology and was identified by DNA sequences. Results One strain of HBoV was detected and identified from 50 samples collected from children with acute respiratory tract infections. This was the first clinical case of HBoV infection reported in Guangdong and was named as GD-1 strain. The HBoV capsid protein (VP) gene amplified from the specimen by PCR was identified by sequencing and was compared with gene sequences in GenBank. Phylogenetic trees were constructed for sequence homology analysis. The nucleotides similarities between GD-1 and Beijing strains, France strains and Canada strains were over 98%, while the simlilarity was over 36% compared with Korea KNIH-2K6GJ2713 strain and over 77% compared with US NH4549 strain. Conclusion HBoV infection does exist in Guangdong Province. It is valuable to start systemic study on it.

Objective To discuss the significance of different types of human rhinovirus (HRV) as pathogen and the clinical features of different types of HRV in pediatric intensive care unit(PICU).Methods Eight hundred and fifty-two nasopharyngeal aspirates specimen (NPA) were collected from children who were admitted to PICU,the Second Affiliated Hospital of Shantou University Medical College from November 2010 to October 2015 and were tested by using nested reverse transcription-polymerase chain reaction (RT-PCR).Gene fragments for VP4/VP2 capsid protein amplified from HRV positive specimens were sequenced for HRV genotype confirmation.Then clinical characteristics of these HRV positive cases were analyzed.Results Among these 852 specimens tested,214 (25.12％) were HRV positive,including 95 samples(44.39％) positive for HRV-A,17 samples (7.94％) for HRV-B,and 55 samples(25.70％)for HRV-C determined by sequence analysis;while the species of 47 samples (21.96％) of the total were unclassified clearly.HRV-A,HRV-B,HRV-C co-infection with other respiratory viruses accounted for 33.68％ (32/95 cases),29.41％ (5/17 cases),and 29.09％ (16/55 cases),respectively.The clinical characteristics of children infected with HRV-A,HRV-B,HRV-C were similar,and wheezing and polypnea were more common with HRV-C infections than HRV-A and HRV-B infections.The severity among children positive for different groups HRV showed no significant difference (H =0.631,P ＞ 0.05),as well as that between children co-infected with HRV and other viruses and those infected with HRV only (H =0.886,P ＞ 0.05).Conclusions Different types of HRV were major causes of infectious disease in pediatric critical disease.The clinical characteristics of children infected with HRV-A,HRV-B,HRV-C were similar.Wheezing and polypnea were more common with HRV-C infections than HRV-A and HRV-B infections.

Objective To discuss the etiology and clinical characteristics of human rhinovirus (HRV) as pathogen of central nervous system infection .Methods Two hundred and five cerebrospinal fluid (CSF) specimens were collected from children with fever and convulsions who were admitted to the pediatric intensive care unit with suspicion of central nervous system infection from June 2011 to December 2012 .Genome Lab Genetic Analysis System (GeXP) was applied to detect HRV from CSF .Specimens with positive results were amplified by nested reverse transcription‐polymerase chain reaction and followed by gene sequencing . Clinical data of HRV positive cases were analyzed . Results Of the 205 CSF specimens ,7 samples were positive for HRV ,which were composed of 2 HRV‐A ,1 HRV‐B and 4 HRV‐C (including 1 HRV‐Ca) .There were 6 boys and 1 girl among the 7 positive cases for HRV .Six children were less than 3 years old ,except one was 9 years old .The onset time was mainly concentrated between September and October . The main clinical manifestations were fever and convulsions . The clinical diagnosis before the pathogen confirmation included viral encephalitis ,epilepsy ,febrile convulsion ,benign infantile convulsions with mild gastroenteritis (CwG ) and hand‐foot‐and‐mouth disease ( HFMD ) . Although the disease severity of the 7 cases varied ,all ended with favorable prognosis .Conclusions HRV is one of pathogens of viral central nervous system infection .All types of HRV can cause central nervous system infection ,among which HRV‐C accounts for the majority .The clinical manifestations of HRV central nervous system infection could mimic febrile convulsion ,CwG and HFMD .

Objective To analyze the clinical features of PICU patients with bocaviral infection.Meth-ods Nasopharyngeai aspirates specimens were collected from 450 children who were admitted to PICU with a-cute respiratory tract infection in our hospital from June 2010 to December 2011 .Multiplex PCR was applied to detected human bocavirus and emerging respiratory virus.Bocavirus positive PCR results were sequenced and the clinical data of the positive cases were analysed.Results Human bocavirus positive samples were detected in 30 cases(6.7%) among 450 throat swab specimens.Human bocavirus as a single infection was found in 16 cases (53.3%).Mixed infections were found with in 14 cases(46.7%) of 30 positive samples.According to pediat-ric critical illness score,there were 13 cases of non-serious,2 cases of serious and 1 case was extremely serious in 16 single infections cases.There were 12 cases of non-seriuo s and 2 serious cases in 14 mixed infections. There were no statistically significant differences between single and mixed infections in the severity of the dis-ease( P>0.05 ) .Conclusion Bocavirus can cause severe respiratory tract infections.Mixed infections does not increase the severity of the disease.

Objective To study the significance of human rhinovirus C as a pathogen and the clini-cal features of human rhinovirus C infection in pediatric intensive care unit. Methods From November 2010 to April 2012,570 nasopharyngeal aspirates specimens were collected from children who were admitted to the pediatric intensive care unit with respiratory infections. Nest reverse transcription-polymerase chain reactions were applied to detect the human rhinovirus C. The other common respiratory viruses were detected by multi-plex polymerase chain reaction. The clinical data were collected. Results One hundred and seventy human rhinovirus positive samples ( 29. 8%) were detected in 570 nasopharyngeal aspirates specimens. The VP2/VP4 and 5′UTR region of the human rhinovirus genome was amplified from 170 human rhinovirus positive samples with 80. 6%(136/170) success. While 20. 0%(34/170) samples in total were unclassified to spe-cies. There were 85 single infected samples including 52 of type A,7 of type B,26 of type C. The nucleotide homology was 74. 0% to 99. 2% and the nucleotide variations was 3. 4% to 32. 3% in stains of human rhino-virus C. The late fall and early winter were the epidemic seasons of human rhinovirus C infection. Cough,fe-ver, polypnea and wheezing were the common symptoms. Conclusion Human rhinovirus C is the major cause of infectious disease in pediatric critical illnesses. Human rhinovirus C infections often cause cough, fever,polypnea and wheezing.

Objective:To analyze the detection rate of respiratory syncytial virus(RSV)and human rhinovirus(HRV), in different months and age groups, and the clinical characteristics in children in eastern Guangdong from 2019 to 2020.Methods:Pharyngeal swabs were collected from 6 658 children with respiratory tract infections hospitalized in the Second Affiliated Hospital of Shantou University Medical College from January 2019 to December 2020, and respiratory pathogen nucleic acid was detected.The detection rate, month distribution, age group distribution, and clinical characteristics of single RSV as well as single HRV positive cases were analyzed and compared.Results:There were 416 single RSV positive cases(6.25%)and 341 single HRV positive cases(5.12%).The detection rates of RSV was higher than those of HRV, and the difference was statistically significant( χ2=7.880, P<0.05).The detection rates of HRV in March, April, November and December were higher than those of RSV, and the detection rates of RSV in July, August and September were higher than those of HRV, with statistically significant difference( P<0.05).The highest detection rate of RSV was in the age group of ≤6 months with a detection rate of 13.47%(192/1 425), which gradually decreased with age, and the difference was statistically significant( P<0.01).The detection rates of HRV fluctuated between 4.21% and 6.13% in each age group, and the differences among the detection rates of each age group were not statistically significant( P>0.05).All RSV-positive cases showed cough, while 77.13%(263/341)of HRV-positive cases showed cough, with a statistically significant difference( P<0.001).The incidence of wheezing in RSV-positive cases was 37.26%(155/416)compared with 28.45%(97/341)in HRV-positive cases, with a higher incidence of wheezing in RSV than that in HRV, and the difference was statistically significant( P<0.05).In terms of indicators to assess severe pneumonia, RSV-positive cases showed a higher proportion of increased respiratory rate, decreased oxygen saturation or dyspnea than HRV-positive cases, and all differences were statistically significant( P<0.05). Conclusion:The detection rate of single RSV is higher than that of single HRV in children with respiratory infections in eastern Guangdong from 2019 to 2020.The epidemic season of RSV is mainly in autumn, and the epidemic season of HRV is mainly in winter and spring.RSV is more susceptible up to 6 months of age, and the detection rate decreases gradually with age, and there is no significant difference in the detection rate of HRV by age.RSV-positive cases are more likely to have cough and wheeze.RSV-positive cases are more likely to have increased respiratory rate, decreased oxygen saturation, or respiratory distress.

Objective To explore the morbidity and clinical characteristics of mumps meningoencephalitis in children without parotitis.Methods Two hundred and twenty-three cerebrospinal fluid (CSF) specimens were collected from children who were diagnosed as viral encephalitis at Department of Pediatrics,the Second Affiliated Hospital of Shantou University Medical College from June 2010 to February 2016.Multiplex PCR was applied to detect the mumps virus,and other common viral,including measles virus,enterovirus,enterovirus 71 type,coxsackie virus A16 type,dengue virus,Japanese encephalitis virus,rubella virus,herpes simplex virus,human cytomegalovirus,Epstein-Barr virus,Chikungunya virus and Charon evagatus in mumps virus positive specimens were detected by PCR.The clinical data of patients with mumps virus infection were analyzed.Results In 223 CSF specimens,positive mumps virus were detected in 11 cases (4.9％),of whom,the mycobacterial,fungal,conventional CSF cultures and other common viral cause in CSF were negative.One case presented parotitis on the sixth day after admission.Of 11 cases with positive mumps virus,there were 10 cases without parotitis.The cardinal symptoms of mumps meningoencephalitis in children without parotitis were fever,headache,vomiting and seizures,and the CSF parameters,brain magnetic resonance imaging,electroencephalogram ofthe patients were all similar to other viral encephalitis,while the prognosis was good in children with mumps meningoencephalitis without parotitis,but the CSF return to normal needed a long time,the longest time up to 4 weeks.Conclusion Mumps meningoencephalitis may occur in children without parotitis,and the most common symptom are fever,headache,vomiting and seizures.

Objective:To investigate the clinical features of adenoviral encephalitis (AE), and to provide reference for clinical diagnosis and treatment of adenoviral encephalitis.Methods:From January 2012 to December 2020, 1 185 cerebrospinal fluid (CSF) samples of hospitalized children with suspected central nervous system infection in the Second Affiliated Hospital of Shantou University Medical College were collected for the detection of 22 common respiratory pathogens and common pathogens for encephalitis by polymerase chain reaction. Records of patients with adenovirus positive in CSF were reviewed and relevant clinical manifestations, laboratory tests and imaging examination results were collected for analysis.Results:Among 1 185 CSF samples, 242 samples were positive for viral nucleic acid, with detection rate of 20.4%, including 1.9%(23/1 185) of adenovirus. As for 23 children diagnosed with AE, 18 were male, five were female, with the age of (44.8±35.9) months, ranging from two months and 19 days to 10 years. Of 23 children, 21(91.3%) presented with fever, followed by convulsions (16 cases, 69.6%), headache (four cases, 17.4%), vomiting (11 cases, 47.8%), consciousness change (11 cases, 47.8%) and emotion disturbance (three cases, 13.0%). Among 23 children, eight cases had white blood cell counts (WBC) of (6 to <10)×10 9/L, 10 cases had WBC of (10 to 20)×10 9/L and the white blood cell classification was mainly neutrophils (21 cases, 91.3%), and C reactive protein of 20 cases (87.0%) was in the normal range. Cerebrospinal fluid examination showed that WBC were less than 15×10 6/L in 20 cases (87.0%), and WBC ≥15×10 6/L in three cases, which were up to 500×10 6/L; the protein of 19 cases was in the normal range, the glucose of 15 cases was in the normal range, and the chloride of 19 cases was in the normal range. Among 16 cases with brain magnetic resonance imaging examination, eight cases did not show abnormality, six cases with local meningeal linear enhancement, one case with small intracranial malacia, and one case with extensive intracranial lesions. For 13 cases who received electroencephalogram (EEG) test, seven cases showed normal EEG or marginal state, four cases showed extensive medium and high amplitude slow wave, one case showed spike wave or spike slow wave and one case had both of the above two changes. Among 23 children, 22 cases recovered including one case had secondary epilepsy, and the remaining one case had severe brain dysfunction and was unable to suck when discharged, with an indwelling gastric tube and accompanied by secondary epilepsy. Conclusions:The clinical manifestations and auxiliary examinations of children with AE have no obvious specificity. Most children with AE have a good prognosis, but a small number of them may have serious sequelae.

Objective:To investigate the complicated virus infection of infants with pertussis and its effect on the disease.Methods:From January 2019 to March 2020, a total of 100 hospitalized infants with pertussis were admitted to the Second Affiliated Hospital of Medical College of Shantou University, nasopharyngeal swabs were collected for detection of ten pathogens including pertussis, namely respiratory syncytial virus(RSV), parainfluenza virus(PIV), bordetella pertussis (BP), human rhinovirus(HRV), human bocavirus(HBoV), human metapneumovirus(hMPV), influenza B virus (INF-B), adenovirus, influenza A virus and cytomegalovirus(CMV). According to the results of pathogen detection, all infants were divided into single detection group of BP(single detection group) and co-detection group of BP combined with viruses(co-detection group). The clinical data of the two groups were retrospectively analyzed and compared to explore the differences of clinical characteristics and its impact on the course of disease.Results:Among 100 cases, there were 54(54.0%) boys and 46(46.0%)girls.The age ranged from 28 days to 2 years and 5 months, with a median age of 3.5 months.Fifty-six cases were classified as single detection group, while 44 cases were included into co-detection group.Among infants in co-detection group, fourteen cases were co-infected with CMV(31.8%, 14/44), seven cases with HRV(15.9%, 7/44), seven cases with PIV(15.9%, 7/44), four cases with RSV(9.1%, 4/44), one case with hMPV(2.2%, 1/44), eight cases with CMV+ HRV(18.2%, 8/44), one case with HRV+ HBoV (2.2%, 1/44), one case with CMV+ PIV(2.2%, 1/44)and one case with CMV+ PIV+ INF-B(2.2%, 1/44). The number of infants in the single detection group who had cyanosis before treatment, requiring repiratory support, PICU admission, severe pneumonia or abnormal myocardial enzymes were higher than those in the co-detection group( P<0.05), while the months of age were lower than that in the co-detection group( P<0.05). When comparing the clinical characteristics of infants over three months of age, only the number of cases of combined cyanosis before treatment and the number of days in hospital were higher in the single detection group than those in the co-detection group ( P<0.05), no statistically significant differences were found in the other clinical characteristics between the two groups( P>0.05). Conclusion:The cases of infants requiring repiratory support, complicated with severe pneumonia or abnormal myocardial enzymes in the single detection group are higher than those in the co-detection group, which may be attributed to the small age of months.

Objective To discuss the change trends of pathogen of severe hand,foot and mouth dis-ease(HFMD) in Chaoshan area during 2011 to 2015. Methods All 1410 throat swabs of cases who were diagnosed as HFMD were collected from children hospitalized in our hospital during May 2011 to August 2015. Enterovirus were detected by nest RT-PCR,and the results of these positive cases diagnosed as severe HFMD were analyzed. Results (1) There were 216 positive cases(67. 29％,216/321) diagnosed as severe HFMD,including 53. 70％ ( 116/216 ) enterovirus 71 ( EV71 ), 19. 91％ ( 43/216 ) coxsackievirus A16 (CA16),12. 04％(26/216) CA6,8. 80％(19/216) CA10,3. 24％(7/216) CA4,0. 93％(2/216) coxsack-ievirus B5, 0. 46％ ( 1/216 ) enteric cytopathogenic human orphan virus and 0. 93％ ( 2/216 ) unclassified samples were unclassified to species. (2) Five cases of critical HFMD were all caused by EV71. (3) The EV71 positive samples were given priority to severe cases ( 51. 79％,116/224 ) and the non EV71 positive samples were given priority to mild cases ( 82. 08％, 458/558 ) , the difference was statistically significant (χ2 =91. 68,P<0. 001). (4) The change trends of severe HFMD year by year were consistent with the change trends of EV71 composition,and were highly correlated(Rs=0. 9,P=0. 037). (5) Severe HFMD caused by non EV71 virus gradually increased. Conclusion Severe HFMD in Chaoshan area during 2011 to 2015 were mainly caused by EV71,non EV71 viruses including CA16,CA6,CA10,CA4,coxsackievirus B5, enteric cytopathogenic human orphan virus 6 could also develop to severe HFMD. The composition ratio of severe HFMD increased accordingly in the year of EV71 as the dominant pathogen. The proportion of severe HFMD caused by non EV71 virus gradually increased after 2013 year.