Adenoviridae ; genetics ; Adenoviridae Infections ; epidemiology ; virology ; Adolescent ; Child ; Child, Preschool ; China ; epidemiology ; Cities ; epidemiology ; DNA, Viral ; analysis ; Humans ; Infant ; Respiratory Tract Infections ; epidemiology ; virology

OBJECTIVETo study the epidemiological characteristics of respiratory adenovirus (ADV) infections in children from the Suzhou area, China.

METHODSThe clinical data of ADV-positive children out of 35 529 children with respiratory tract infections who were hospitalized in the Children's Hospital of Soochow University between January 2006 and December 2015 were retrospectively studied.

RESULTSOf the 35 529 children with respiratory tract infections, 440 (1.24%) were ADV-positive. There was no significant difference in the rate of ADV infections between boys and girls (1.18% vs 1.34%). The ADV infection rates of children at the age of <1 year old, 1-3 years old, 3-7 years old and 7-14 years old were 0.39% (71/18 002), 1.12% (103/9 191), 3.14% (201/6 398), and 3.35%( 65/1 938) respectively and the rate increased with age (P<0.01). The ADV infection rates in spring [1.85%(60/8 658)] and summer [2.20%(189/8 606)] were significantly higher than in autumn [0.30%(27/8 952)] and winter [0.69%(64/9 313)] (P<0.01).

CONCLUSIONSThe ADV infection rate is increased with age in the children from the Suzhou area, but it is not associated with gender. ADV infections are more common in spring and summer.

Adenoviridae Infections ; epidemiology ; Adolescent ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Male ; Respiratory Tract Infections ; epidemiology ; Time Factors

Acute Disease ; Adenoviridae Infections ; epidemiology ; Adolescent ; Child ; Child, Preschool ; China ; epidemiology ; Humans ; Infant ; Infant, Newborn ; Respiratory Tract Infections ; epidemiology ; virology

UNLABELLEDTo investigate the epidemiological features and types of human adenoviruses (ADV) in children with acute respiratory tract infection in Nanjing area, China. Nasopharyngeal aspirates and nasopharyngeal swabs were collected from 644 outpatients or hospitalized pediatric patients with ARTI at the Children Hospital of Nanjing, Jiangsu Province, China, between August 2010 and July 2011. Adenoviruses were identified and typed from the collected clinical specimens by nested-PCR based on the partial region of the hexon gene. Other 12 respiratory viruses including human bocavirus (HBoV), respiratory syncytial virus (RSV), human rhinovirus (HRV), parainfluenza viruses 1-4 (PIV1-4), influenza virus A/B (IFVA/B), human metapneumovirus (HMPV), human coronavirus NL63 and HKU1 (HCoV-HKU1 and HCoV-NL63) were also identified by PCR method. All PCR positive products were sequenced and phylogenetic analysis was conducted. It was showed that adenoviruses were detected in 171 patients out of 644 (26. 55%) children, 120 (70.18%, 120/171) for ADV3, 16 (9.36%,16/171) for ADV7, 12 (7.02%, 12/171) for ADV1, 10 (5.85%, 10/171) for ADV2, 6 (3.51%, 6/171) for ADV5, 3 (1.75%, 3/171) for ADV6, 3 (1.75%, 3/171) for ADV57, and 1 (0.58%,1/171) for ADV41. ADV infection could occur in any season. There was a higher possibility of ADV infection from April to July in 2011. Most cases (96.49%) were younger than 7 years old. A total of 99 of the 171 ADV-positive children (57.89%) were co-infected with other respiratory viruses. Respiratory syncytial virus (RSV) and human rhinovirus (HRV) were the most common additional respiratory viruses, Lower respiratory tract infections were the most frequent diagnoses made in the hospital, in which there were 52 pneumonia (30.4%) cases.

CONCLUSIONADV is one of the most important pathogens of acute respiratory tract infection in children in Nanjing area, and adenovirus type 3 was the most prevalent serotype. It is important to develop long-term surveillance.

Adenoviridae ; classification ; genetics ; isolation & purification ; Adenoviridae Infections ; epidemiology ; virology ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Male ; Molecular Sequence Data ; Phylogeny ; Respiratory Tract Infections ; epidemiology ; virology

Adenoviridae ; classification ; genetics ; pathogenicity ; Adenoviridae Infections ; epidemiology ; prevention & control ; virology ; Age Distribution ; Child, Preschool ; Humans ; Infant ; Infant, Newborn

OBJECTIVEAdenovirus (ADV) is one of the most common causes of acute respiratory infections in infants and children. The objective of this study was to investigate the prevalence of adenovirus infection among pediatric patients with acute respiratory infections in Beijing and the types of the adenoviruses circulating in Beijing on the molecular bases.

METHODClinical specimens including throat swabs from outpatients and nasopharyngeal aspirates from hospitalized patients were collected from patients with acute respiratory infections in a consecutive period of 6 years from Jan 2003 to Dec 2008. Adenoviruses were identified from the collected clinical specimens by tissue culture and/or immunofluorescence assay and typed by nested-PCR based on the sequence of the encoding gene of hexon. Primers were designed for PCR amplification using hexon gene of adenovirus as target. One primer pair was designed as universal primers for amplifying a 1278 bp gene fragment located at the hexon gene of adenovirus types 3, 7, 11 and 21. Four primer pairs with the sequences located within the region of this 1278 bp fragment were designed specifically for amplifying adenoviruses types 3, 7, 11 or 21, respectively, which were used for a multiplex nest-PCR in a single tube. The products from this multiplex nest-PCR were 502 bp (for type 3), 311 bp (for type 7), 880 bp (for type 11) and 237 bp (for type 21), respectively, and the type of the adenovirus tested can be determined after agarose electrophoresis analysis of the PCR products. For those strains which could not be typed by the multiplex nest-PCR, the gene fragment was amplified by a universal primer pair for all adenovirus types from group A to F and the PCR products were sequenced directly.

RESULTOut of 17 941 clinical specimens collected, including 4378 throat swabs from outpatients and 13 563 nasopharyngeal aspirates from hospitalized patients, 304 were adenovirus positive by tissue culture and/or immunofluorescence assay, the overall positive rate was 1.69% (304/179 41). Among these 304 adenovirus positive specimens, 184 were by virus isolation and 184 by immunofluorescence assay, among which 64 were positive by both methods. The types of the adenoviruses were tested for 285 patients including 174 viral isolates and 111 clinical specimens. By using the multiplex nest-PCR, 272 were typable, including 174 (61.1%, 174/285) for ADV3, 92 (32.3%, 92/285) for ADV7, 6 for ADV11 (2.1%, 6/285) and no adenovirus type 21 was detected. Sequence analysis for those 13 nontypable specimens by the multiplex nest-PCR showed that 9 were ADV2 (3.2%, 9/285), 2 were ADV6 (0.7%, 2/285), 1 was ADV1 (0.4%, 1/285) and 1 was ADV5 (0.4%, 1/285). Most of the patients positive for adenovirus were under 5 years of age and 64.4% were from patients with lower respiratory infections, such as bronchiolitis and pneumonia. All the 5 cases of severe pneumonia with pulmonary failure were caused by ADV7 infection.

CONCLUSIONAdenovirus is still an important pathogen for acute respiratory infection in infants and young children and most of the adenoviruses associated with acute respiratory infections in children in Beijing from 2003 to 2008 were ADV3 and ADV7. ADV7 could cause severe lower respiratory infections.

Acute Disease ; Adenoviridae ; classification ; isolation & purification ; Adenoviridae Infections ; epidemiology ; prevention & control ; Adolescent ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Prevalence ; Respiratory Tract Infections ; epidemiology ; prevention & control ; virology

OBJECTIVEThe study was designed to evaluate adenovirus infection in hospitalized children with diarrhea.

METHODStool specimens were collected from 519 hospitalized children with diarrhea during 2010, including those defined as community-acquired diarrhea (CAD) who developed diarrhea symptoms within 48 hours after admission, and those defined as hospital-acquired diarrhea (HAD) whose symptoms of diarrhea occurred beyond 48 hours after admission. PCR was employed to identify adenovirus in fecal samples by using universal primers for adenoviruses of all types, and specific primers for adenovirus group F. PCR products with expected size were sequenced for adenovirus typing. Clinical data for children with adenovirus positive specimens were analyzed.

RESULTA total of 519 hospitalized children, including 289 with CAD and 230 with HAD, were enrolled in the study. Out of 519 stool specimens, 76 showed PCR products with expected 301 bp and identified as adenovirus by sequencing, and the overall positive rate was 14.6%. Out of 289 CAD samples, 43 were positive (positive rate was 14.9%). Of them, 20 were identified as enteric adenovirus infection (adenovirus type 41, Ad41). Thirty-three out of 230 HAD samples were positive (positive rate was 14.3%). Of them, 13 were characterized as enteric adenovirus infection (one was Ad40 and others were Ad41). Ad41 in this study could be divided into two genotypes by phylogenetic tree analysis. Non-enteric adenoviruses were identified in 43 specimens (43/76, 56.6%) including 5 of serotype 1, 8 of serotype 2, 15 of serotype 3, 10 of serotype 7, 1 of serotype 12, and 4 of serotype 31. In this study, the positive rate of adenovirus between CAD children and HAD children did not differ (χ(2) = 0.03, P > 0.05), while the positive rate of enteric adenovirus was high in CAD children.

CONCLUSIONAdenovirus infection was the main cause of diarrhea in hospitalized children. In this study, the positive rate of adenovirus was similar between children with CAD and with HAD. Enteric adenovirus (adenovirus group F) was the most common adenovirus serotype detected in 2010 in Beijing, and Ad41 was the dominant type.

Adenoviridae ; classification ; genetics ; isolation & purification ; Adenoviridae Infections ; epidemiology ; Age Distribution ; Child, Hospitalized ; Child, Preschool ; China ; epidemiology ; DNA, Viral ; analysis ; Diarrhea ; epidemiology ; virology ; Diarrhea, Infantile ; epidemiology ; virology ; Feces ; virology ; Female ; Humans ; Infant ; Male ; Polymerase Chain Reaction ; Sex Distribution

PURPOSE: Acute respiratory tract infections are the most common illnesses in children. The great majority of these infections involving lower respiratory tracts infections(LRTIs) are caused by respiratory viruses such as respiratory syncytial virus(RSV), parainfluenza virus(PIV), influenza virus (Flu), and adenovirus(ADV), etc. Our purpose was to determine seasonal epidemiology and clinical characteristic features of each viral infection. METHODS: Nasopharyngeal aspirate(NPA)s were collected from 4,554 hospitalized children diagnosed as LRTIs on the first day of admission. The study period was from September 1998(Autumn) through May 2003(Spring). Respiratory viruses were detected in 881(19 percent) cases by isolation of the virus or by antigen detection method using indirect immunofluorescent staining. We reviewed the medical records of 837 cases retrospectively. RESULTS: The identified pathogens were RSV in 485 cases(55 percent), PIV in 152 cases(17 percent), FluA in 114 cases(13 percent), ADV in 79 cases(9 percent) and FluB in 51 cases(6 percent). Outbreaks of RSV occurred every year, mostly in the November through December period and of PIV in the April through June period. LRTIs by FluA reached the highest level in January, 2002. FluB infection showed an outbreak in April, 2002. The clinical diagnoses of viral LRTIs were bronchiolitis in 395 cases(47 percent), pneumonia in 305 cases(36 percent), croup in 73 cases(9 percent) and tracheobronchitis in 64 cases(8 percent). CONCLUSION: Viruses are one of the major etiologic agents of acute LRTIs in chidren. Therefore, we must continue to study their seasonal occurrence and clinical features to focus on management, and also for reasons of prevention.
Adenoviridae ; Bronchiolitis ; Child ; Child, Hospitalized ; Croup ; Diagnosis ; Disease Outbreaks ; Epidemiology* ; Humans ; Medical Records ; Orthomyxoviridae ; Paramyxoviridae Infections ; Pneumonia ; Respiratory Syncytial Viruses ; Respiratory System* ; Respiratory Tract Infections* ; Retrospective Studies ; Seasons

BACKGROUND: The information on the incidence, seasonal variation and clinical pattern of respiratory virus infections is very important for clinicians in managing their patients. This study was aimed to define the epidemiology of respiratory viral pathogens in Seoul and the neighboring areas from March 2004 to February 2006. METHODS: A total of 6,533 specimens were cultured for respiratory viruses during the study period. Madin-Darby canine kidney (MDCK), LLC-MK2, and HEp-2 cells, or R-mix cells (Diagnostic Hybrids Inc., Athens, Ohio, USA) were used for culture. Influenza virus types A & B (Inf A & B), parainfluenza virus (PIV), respiratory syncytial virus (RSV), and adenovirus (ADV) were identified by indirect immuno-fluorescent staining. Medical records of the patients with positive virus cultures were reviewed retrospectively. RESULTS: One or more viral agents were isolated from 1682 specimens (25.7%). The pathogens identified were RSV 37.2%, ADV 19.9%, Inf A 18.9%, PIV 17.5% and Inf B 6.4%. The most frequent pathogen of pneumonia and acute bronchiolitis was RSV and that of croup was PIV. Upper respiratory tract infections were more prevalent in adults and the most frequently caused by influenza virus. Influenza virus itself was more frequently isolated in children less than six years old, which was different from previous reports. Influenza virus was mostly isolated in the winter and spring, while RSV was usually isolated from early fall with a peak incidence in the winter. Inf A and RSV showed a dampening effect on the occurrence of other viruses during their major epidemic. PIV was mostly detected in the spring and summer. ADV was isolated throughout the whole year. CONCLUSIONS: The epidemiological characteristics of respiratory virus infections in Seoul and the neighboring areas in 2004-2006, were similar to the findings of previous reports except for some minor changes. These findings could be useful to clinicians in managing their patients.
Adenoviridae ; Adult ; Bronchiolitis ; Child ; Croup ; Epidemiology* ; Humans ; Incidence ; Kidney ; Medical Records ; Ohio ; Orthomyxoviridae ; Paramyxoviridae Infections ; Pneumonia ; Respiratory Syncytial Viruses ; Respiratory Tract Infections ; Retrospective Studies ; Seasons ; Seoul

BACKGROUND: Studies on the incidence and seasonality of respiratory viruses that are the main cause of lower respiratory tract disease in children are insufficient in Korea. In the present study, the epidemiology of respiratory viruses in children was studied during the last 2 years and, the indirect immunofluorescent (IF) method was compared with the direct IF method. METHODS: A total of 814 pediatric inpatients hospitalized for lower respiratory tract infection at Hanyang University Hospital were studied from April, 1996 to July, 1998. Nasopharyngeal aspirates were obtained from these patients and indirect IF (Respiratory Panel I Viral Screening & Identification Kit, Light Diagnostics, Chemicon, Temecula, CA, USA) was performed for the following viruses : respiratory syncytial virus (RSV), parainfluenza virus type I, II and III, influenza virus A, B, and adenovirus. Sixty-nine of these samples were tested by direct IF (IMAGENTM, DAKO, UK) and indirect IF, simultaneously. RESULTS: 1) Viral pathogens were detected in 30.5% of nasopharyngeal aspirates. Among the positive cases, RSV was 60.6%, influenza A 35.3%, adenovirus 5.2%, influenza B 4.0%, and parainfluenza II 0.8%. 2) The occurrence rate of RSV in spring, summer, fall and winter was 7.3%, 13.6%, 31.45%, 33.45%, respectively, and showed a unique pattern in that the incidence rate in the summer of 1997 was 22.2%. A unique pattern was also observed for influenza A, which was continuously detected from December 1997 to July 1998. 3) The positive rate of indirect IF was statistically higher than that of direct IF. Excluding the results of the influenza A, there was no statistically significant difference between the two methods. CONCLUSION: RSV was the most frequently detected virus in viral respiratory infections in children. Infection usually began in the fall and most frequently detected in the winter and lasted until spring. High incidence of RSV in summer 1997 and continuous detection of influenza A till summer 1997 suggest some change of epidemic pattern. The discordance between direct and indirect IF was probably due to the difference in quality of the anti-influenza A reagent rather than a real difference in the two methods.
Adenoviridae ; Child* ; Epidemiologic Studies* ; Epidemiology ; Humans ; Incidence ; Influenza, Human ; Inpatients ; Korea ; Mass Screening ; Orthomyxoviridae ; Paramyxoviridae Infections ; Respiratory Syncytial Viruses ; Respiratory Tract Diseases ; Respiratory Tract Infections ; Seasons