Prevalence Of Respiratory Viruses Research Articles

Respiratory viruses in children attending Kindergarten

No: 1626 Presentation at ESCV 2015: Oral 16 Routine sequencing of enteroviruses in clinical materials identifies the presence of new Group-C enterovirus types in the Netherlands C.C. Van Leer-Buter1,∗, R. Poelman1, R. Borger1, J. Weel2, C.H. Benne3, H.G.M. Niesters1 1 Division of Clinical Virology, Department of Medical Microbiology, University of Groningen, The Netherlands 2 Izore, Laboratory for Medical Microbiology, Leeuwarden, The Netherlands 3 CERTE Laboratory for Infectious Diseases, Groningen, The Netherlands Background: Enteroviruses (EV) that infect humans belong to four EV groups (A–D) while the rhinoviruses can be divided into three genogroups (A–C). While rhinoviruses are seen primarily as respiratory pathogens, EV can cause a wide variety of diseases in affecting different organ systems, The fact that respiratory infections may be caused by EV infections has been clear since the identification of EV-D68 in 1962. During the summer and fall of 2014, the largest EV-D68 outbreak took place in the USA and it was shown that the strains of the EV-D68 outbreak in North America also circulated in Europe. EV types are defined by sequence divergence in the VP-1 capsid coding region. Ongoing mutations and recombination of the viruses is causing the appearance of new EV types. The newest additions to the expanding cloud of EV typeswere identified either as new variants found in the poliovirus surveillance programs or in respiratory secretions that were sampled as part of studies investigating respiratory viruses. Methods: During a four-year period, all samples from patients with clinical presentations compatible with EV infections were screened using a laboratory-developed test All EV isolates were subsequently genotyped by sequencing the VP1 region. To complete the data with samples from secondary hospital care and general practice, EV isolates from two regional laboratories were included in the routine genotyping program. Results: Enteroviruses were detected in 657 clinical samples, and genotypes could be obtained from 607. EV was detected in 88 CSF samples, 7 vesicular fluids, 13 plasma and serum samples, 85 respiratory samples, and in 338 fecal samples. 76were unidentified materials from general practice. Genotypes from all four EV groups were found with EV-D68 being the only representative of group D. Group C enteroviruses were found either in respiratory samples and/or fecal samples. In respiratory materials, we found the following group C enteroviruses: CV-A21 (n=4), EV-C104 (n=1), EV-C105 (n=1), EV-C109 (n=5), and EV-C117 (n=1). Phylogenetic analysis shows that the four CV-A21 isolates are similar to the isolates found in North America in 2006. The EV-C109 isolates show 8–10% divergence from the other stains identified to date. Conclusion: Enteroviruses are increasingly identified as causes or respiratory disease. Routine screening followed by sequencing provides essential information about which enteroviruses are circulating and how new genotypes evolve. http://dx.doi.org/10.1016/j.jcv.2015.07.026 Abstract No: 1519 Presentation at ESCV 2015: Oral 17 Respiratory viruses in children attending Kindergarten N. Moe1,∗, L.H. Skanke1, S.A. Nordbo2, S. Krokstad2, A. Smyrnaios1, H. Dollner1 1 Department of Pediatrics, St. Olavs Hospital, Trondheim University Hospital, Norway 2 Department of Medical Microbiology, St. Olavs Hospital, Trondheim University Hospital, Norway Background: Many studies have investigated the prevalence of respiratory viruses in hospitalized children, but little is known about this prevalence outside hospitals. Methods: We examined 1–6 years old children attending 2 kindergartens four times from 2012 to 2014 and included a total of 379 cases. Near 80% of all children participated in the study. The children were clinically examined by a pediatrician for signs of respiratory tract infection (RTI). A nasopharyngeal swap was used to collect a nasopharyngeal secrete (NPS) at each examination and was analyzed by in-house real-time PCRs for a panel of 16 respiratory viruses. Results: NPS was positive for at least one virus in 42.5% of the cases, of which 30.6% had one virus and 11.9% had two or more viruses. Rhinovirus was detected in 24.2% of the samples, enterovirus in 11.7% and parechovirus in 8.7%. Adenovirus, human bocavirus, coronavirus-OC43/NL63/229E, influenza A and B virus, human metapneumovirus, parainfluenza virus type 1–4 and RSV were each detected in 0.3–2.6% of the samples. In two-thirds of the examinations, the children had clinically signs of a RTI. Children with clear signs of a RTI had frequently 1 or more viruses (70%), compared to childrenwith amilder RTI (40%) and childrenwithout signs of RTI (28%) (p<0.001). Conclusions:This is thefirstNorwegian study screeningkindergarten children with an extensive panel of respiratory viruses along with clinical examination. Surprisingly two-thirds of children attending Norwegian kindergartens had mild or clear signs of an upper respiratory tract infection. Our results furthermore showed a high prevalence of picornaviruses (rhino-, enteroand parechovirus) in childrenwith RTI, but even childrenwithout signs of RTI had often a positive PCR-test for picornaviruses. http://dx.doi.org/10.1016/j.jcv.2015.07.027

Prevalence of respiratory virus in symptomatic children in private physician office settings in five communities of the state of Veracruz, Mexico.

BackgroundAcute respiratory tract infections are the leading cause of morbidity and mortality in children worldwide. Many studies have described the frequency of viruses in hospitalized patients, but studies describing the prevalence of viruses in the community setting are limited, particularly in developing countries, where most of the deaths from serious respiratory diseases occur. The aim of this study was to evaluate the diversity of respiratory viruses in the community setting using molecular diagnostic tools, as well as the clinical characteristics of respiratory viral infections in the general pediatric practice in Mexico.MethodsChildren with respiratory tract infections attending private pediatric practices during a 10-month period in five cities of the state of Veracruz were included. Nasal swabs were taken and processed by a multiplex detection kit for 15 respiratory viruses.Results525 children were included from July 2011 to May 2012; 44% were female, mean age was 45 months. The 3 most frequent clinical diagnosis were: rhinopharyngitis 68%, pharyngitis 18%, and 3.3% influenza-like illness. 71.5% of the samples were positive for virus. The five most frequent pathogens were respiratory syncycitial virus in 18.3% of the children, rhinovirus in 17.5%, influenza A 9.1%, adenovirus 7.2%, and enterovirus 3.4%, although all 15 viruses were detected; there were viral coinfections in 14.1%, and 28.5% of the samples were negative.ConclusionsA large proportion of respiratory infections in the community setting in Mexico was associated to viruses. Although testing for common respiratory pathogens in children with acute respiratory tract infections may lead to a better understanding of the role of viral pathogens in, and eventually to improvement in the management of, individual patients, additional prospective studies are required to study the need of routinely using such tests in general pediatric practices in resource-limited countries.

Prevalence and seasonal distribution of respiratory viruses in patients with acute respiratory tract infections, 2002-2014

The aim of this study was to investigate the prevalence and seasonal distribution of respiratory viruses in pediatric and adult outpatients and inpatients who were admitted to hospital with the symptoms of upper and lower respiratory tract infections, during a 12-year period. A total of 5102 clinical samples (4372 nasopharyngeal swabs, 316 bronchoalveolar lavages, 219 transtracheal aspirates, 163 nasopharyngeal aspirates, 20 sputum, 10 nasal swabs) examined in our laboratory between January 1st 2002 and July 17th 2014, were evaluated retrospectively. Of the specimens, 1107 (21.7%) were obtained from outpatients and 3995 (78.3%) from hospitalized patients. Of the patients, 2851 (55.9%) were male and 2251 (44.1%) were female, while 1233 (24.2%) were adults and 3869 (75.8%) were children (age range: 1 day - 93 years; median: 3 years). Respiratory samples were investigated for the presence of respiratory syncytial virus (RSV), influenza virus type A and B (INF-A, INF-B), adenovirus (AdV), parainfluenza viruses (PIV types 1-4), human rhinoviruses (HRV), human coronaviruses (HCoV), human metapneumovirus (HMPV) and human bocavirus (HBoV). All specimens were tested by both direct immunofluorescence antibody (DFA) and shell vial cell culture (SVCC) methods. In DFA assay the samples were initially screened by fluorescent-labeled polyclonal antibodies, and the positive ones were typed by using monoclonal antibodies (Light Diagnostics, Merck Millipore, USA). In SVCC, HEp-2, MDCK, A-549 and Vero cell lines were used for the isolation of viruses. In addition to these methods, real-time multiplex PCR methods (RealAccurate®, Respiratory RT PCR, PathoFinder, Netherlands and Seeplex® RV15 ACE Detection, Seegene, South Korea) were used for the detection of respiratory viruses in samples (n= 2104) obtained from 2007 to 2014. Respiratory viruses were detected in a total of 1705 (33.4%) patients, of them 967 (19%) were male and 738 (14.4%) were female. Three hundred and eighteen (18.6%) of the 1705 patients were infected with multiple respiratory viruses. The most frequently observed co-infections were RSV+INF-A (40/318; 12.6%), and RSV+PIV (33/318; 10.4%). The rate of positivity for the respiratory viruses in pediatric and adult groups were 35.4% (1369/3869) and 27.3% (336/1233), respectively (p< 0.000). The most frequently detected virus in pediatric group was RSV (336/1369; 24.5%), followed by influenza viruses (314/1369; 22.9%), PIV (197/1369; 14.4%), HRV (118/1369; 8.6%), AdV (75/1369; 5.5%) and the others (49/1369; 3.6%). On the other hand the most frequently detected virus in adult group was influenza viruses (181/336; 53.8%) followed by AdV (37/336; 11%), RSV (24/336; 7.1%), PIV (24/336; 7.1%), HRV (23/336; 6.8%) and the others (9/336; 2.7%). The rate of multiple virus infections in pediatric and adult groups were 7.2% (280/3869) and 3% (38/1233), respectively. Most of the coinfections (280/318; 88%) were detected in children. Respiratory viruses were detected positive in 40.2% (445/1107) of outpatients, and in 31.5% (1260/3995) of inpatients (p< 0.000). The most frequent viruses detected in pediatric outpatients and inpatients were HRV and RSV, respectively, while influenza viruses were the first in line among both adult outpatients and inpatients. During the study period, a PIV-3 outbreak (n= 96) have emerged between December 2004-April 2005, and an influenza A (H1N1)pdm09 outbreak (n= 207) between November 2009-January 2010. When the seasonal distribution was considered, the isolation rates of 1705 respiratory viruses in winter, spring, summer and autumn were 44.4%, 27%, 8.3% and 20.3%, respectively. RSV was most frequently detected from December to March, influenza viruses from November to March, HRV from December to June, and mixed infections from January to February. In conclusion, the data of our study obtained in about 12-year period indicated that the prevalence of respiratory viruses in acute respiratory infections is 33.4%, and they typically active during the months of winter and early spring in our region.

Respiratory viruses within homeless shelters in Marseille, France

BackgroundHomeless shelters are identified as places where humans are at high risk of acquiring respiratory disease. We previously reported the prevalence of the main respiratory diseases affecting a population of homeless in Marseille, France. Here, we investigated the prevalence of 10 respiratory viruses in a similar homeless population during 2 successive winter seasons.FindingsFollowing a clinical examination, we collected nasal specimens from which the RT-PCR detection of 10 respiratory viruses was performed through snapshot investigations. Among the 265 patients included, 150 (56.6%) reported at least one respiratory symptom of which 13 (8.7%) had positive swabs for at least one respiratory virus, and 115 patients reported any respiratory symptom of which 10 (8.7%) had positive swabs for respiratory virus. Overall, 23 patients had positive swabs for at least one respiratory virus. Human rhinovirus (HRV) was the predominant virus (13 isolates) followed by enteroviruses (3), human metapneumovirus (2), human coronavirus OC43 (2), 229E virus (2) and human respiratory syncytial virus subtype B (1). Among the patients infected with HRV, 10 were collected during the same snapshot.ConclusionsAlthough one half of the patients reported respiratory symptoms, the prevalence of respiratory viruses was within the range of that previously described in adult asymptomatic patients outside the homeless community. Most HRV-positive swabs were collected during the same snapshot suggesting a local outbreak. No influenza viruses were found despite the fact that one half of the patients were investigated during the peak of the seasonal influenza epidemic in Marseille.

Lower airway sampling greatly increases detection of respiratory viruses in critically ill patients: the COURSE study

The prevalence of viral respiratory infections in critically ill patients on the ICU and the diagnostic potential of tracheal aspirate sampling are unknown. For this study, the prevalence of respiratory viruses was investigated in intubated patients by simultaneous sampling of nasopharynx and tracheal aspirate.

Respiratory viral infections and effects of meteorological parameters and air pollution in adults with respiratory symptoms admitted to the emergency room

BackgroundRespiratory viral infections (RVIs) are the most common causes of respiratory infections. The prevalence of respiratory viruses in adults is underestimated. Meteorological variations and air pollution are likely to play a role in these infections.ObjectivesThe objectives of this study were to determine the number of emergency visits for influenza-like illness (ILI) and severe acute respiratory infection (SARI) and to evaluate the association between ILI/SARI, RVI prevalence, and meteorological factors/air pollution, in the city of Porto Alegre, Brazil, from November 2008 to October 2010.MethodsEleven thousand nine hundred and fifty-three hospitalizations (adults and children) for respiratory symptoms were correlated with meteorological parameters and air pollutants. In a subset of adults, nasopharyngeal aspirates were collected and analyzed through IFI test. The data were analyzed using time-series analysis.ResultsInfluenza-like illness and SARI were diagnosed in 3698 (30·9%) and 2063 (17·7%) patients, respectively. Thirty-seven (9·0%) samples were positive by IFI and 93 of 410 (22·7%) were IFI and/or PCR positive. In a multivariate logistic regression model, IFI positivity was statistically associated with absolute humidity, use of air conditioning, and presence of mold in home. Sunshine duration was significantly associated with the frequency of ILI cases. For SARI cases, the variables mean temperature, sunshine duration, relative humidity, and mean concentration of pollutants were singnificant.ConclusionsAt least 22% of infections in adult patients admitted to ER with respiratory complaints were caused by RVI. The correlations among meteorological variables, air pollution, ILI/SARI cases, and respiratory viruses demonstrated the relevance of climate factors as significant underlying contributors to the prevalence of RVI.

Prevalence of Respiratory Viruses in Chronic Rhinosinusitis and Its Influence on the Mucosa

Objectives: Find a correlation between the presence of respiratory viruses and the pathogenesis of chronic rhinosinusitis (CRS). Methods: Prospective cross-sectional study. Genomes of respiratory viruses in patients were analyzed by real-time polymerase chain reaction (PCR) in samples of nasal washes and nasal tissue samples obtained from both CRS with polyps (CRSwNP) and without nasal polyps (CRSsNP). Histological analysis was also performed to quantify eosinophils, neutrophils, and lymphocytes. Results: A total of 132 patients were evaluated, 31 controls, 31 patients with CRSsNP, and 70 patients with CRSwNP. Considering all samples together, human metapneumovirus (HMPV) and human rhinovirus (HRV) were the most frequently detected virus genomes found in CRS patients, present in respectively 19 of 70 and 16 of 70 of patients with CRSwNP, as opposed to 5 of 31 of HMPV and 4 of 31 of HRV in those with CRSsNP. In CRSsNP the virus presence was associated with a lower count of lymphocytes and neutrophils, but not to eosinophils count. In CRSwNP group, the virus presence was associated to a higher count of lymphocytes and neutrophils and to a lower count of eosinophils. Regarding rhinovirus presence, no cell count was associated with its presence in CRSwNP, and in CRSsNP the rhinovirus presence was associated only with a lower count of lymphocytes. Conclusions: The high detection of respiratory viruses in these patients highlights the need for further studies detailing possible roles that these ubiquitous respiratory agents may have in the pathogenesis of CRS.

Respiratory virus identification by interval polymerase chain reaction testing in the southeastern United States

This study was designed to determine if testing the first ~40 nasal washings (interval) each month for 1 year, could be used as an epidemiologic tool for seasonality and prevalence of respiratory viruses such as human metapneumovirus in an adult and pediatric population in the southeastern United States. Results of interval polymerase chain reaction (PCR) testing of 469 specimens for 8 viruses were compared with our current procedures using PCR, culture, or respiratory synctial virus antigen for all 7435 specimens (routine). One hundred thirty-six viruses out of 469 specimens (29.0%) and 1,495 viruses out of 7,435 specimens (20.1%) were identified by interval and routine testing, respectively. Seasonal detection varied among viruses and to some degree between interval and routine testing. A higher percent of positives and dual infections were detected by interval testing of pediatric specimens, likely due to the use of PCR for viruses commonly seen in this population. Human metapneumovirus was detected in both pediatric and adult specimens between January and August. Interval testing can be used to provide a snapshot of prevalence and seasonality of respiratory viruses, although as currently designed they may not be sensitive enough to identify the beginning of a specific virus season. Exclusive use of interval PCR testing identified several dual infections, including human metapneumovirus, throughout most of the year in Florida. A rapid turnaround time to results translates into improved infection control and improved patient care.

FRECUENCIA DE LOS VIRUS PARA INFLUENZA-3, RESPIRATORIO SINCITIALY DIARREA VIRAL BOVINA EN UN REBAÑO MIXTO DE UNA COMUNIDAD CAMPESINA DE CUSCO

A serologic study was conducted to determine the prevalence of Parainfluenza-3 virus (PI3V), Syncytial Respiratory virus (RSV) and Bovine Viral Diarrhea virus (BVDV) in ruminants raised under harsh environmental conditions and poor management in the highlands of Cusco, Peru. Blood samples were collected in cattle (n = 66), alpaca (n = 21), and sheep (n = 152) for antibody detection against PI3V, RSV, and BVDV by serum neutralization test. The prevalence of PI3V, RSV, and BVDV was 81.8, 87.8, and 90.9% in cattle, 50.0, 49.3, and 28.3% in sheep, and 23.8, 4.7, and 15.8% in alpaca respectively. The antibody titers ranged from 2 to >256 and the highest titers were found in bovine samples. The results indicate that these respiratory viruses are widely distributed in the animals of this rural community and may play a key role in respiratory problems.

The prevalance of respiratory viruses among healthcare workers serving pilgrims in Makkah during the 2009 influenza A (H1N1) pandemic

SummaryDespite the high risk of acquiring respiratory infections, healthcare workers who treat pilgrims at Hajj have not been studied in previous research on respiratory diseases during Hajj. The objective of this study was to determine the prevalence of different respiratory viruses among healthcare workers who treated pilgrims during Hajj 2009, the year of the influenza A H1N1 pandemic. A cross-sectional study was performed just before and after Hajj (25–29 November, 2009). Nasal and throat swabs were tested for 18 respiratory virus types and subtypes. A total of 184 healthcare workers were examined. Most were men (85%) with an average age of 41 years. Before the Hajj, rates of seasonal influenza vaccination were higher (51%) than rates of pandemic influenza A H1N1 vaccination (22%). After the Hajj, participants reported high rates of maintaining hand hygiene (98%), cough etiquette (89%), and wearing a face mask (90%). Among all the viruses tested, only two were detected: rhinovirus was detected in 12.6% and Coronavirus 229E in 0.6%. Rhinovirus was detected in 21% of those who had respiratory symptoms during Hajj. Influenza A (including H1N1), influenza B. respiratory syncytial virus, other coronaviruses, parainfluenza viruses, human metapneumovirus, adenovirus, and human bocavirus were not detected. The finding of high rates of rhinovirus infection corresponds to their frequent occurrence in adults. None of the participants had influenza A H1N1 2009, possibly because it was also infrequent among the 2009 pilgrims.

Characteristics and the prevalence of respiratory viruses and the correlation with climatic factors of hospitalized children in Suzhou children's hospital

To study the epidemiological characteristics of respiratory virus infection and its relations to climatic factors in Suzhou. From 2006 to 2009, viral etiology surveillance was conducted among 6655 children hospitalized with acute respiratory tract infections (ARIs). Direct immunofluorescence method was used to test respiratory secretion samples for respiratory syncytial virus (RSV), influenza viruses A and B (Inf-A, Inf-B), parainfluenza virus types I, II, and III (Pinf-I, Pinf-II, Pinf-III) and adenovirus. Samples were tested for human metapneumovirus (hMPV) with reverse transcription polymerase chain reaction (RT-PCR). Samples from Jan 2006 to Dec 2009 were also tested for human bocavirus (HBoV). Climatic factors, including mean temperature, relative humidity, rainfall amount, sum of sunshine and mean wind velocity were collected monthly. The relationship between activity of each virus and climatic factors were analyzed by linear regression and stepwise regression analysis. From 2006 to 2009, in the total virus detection rate was 32.2% (2142/6655) in Suzhou. RSV was the most common virus and the average detection rate was 15.7% (1048/6655), followed by hMPV 8.9% (596/6655), HBoV 7.8% (148/1883), Pinf-III 2.7% (183/6655), Inf-A 2.4% (161/6655), ADV 1.3% (89/6655), Pinf-I 0.4% (29/6655), Inf-B 0.37% (25/6655) and Pinf-II 0.16% (11/6655). The positive rates of RSV, hMPV and ADV were significantly different in four years (χ(2) = 17.71, 33.23, 8.42, all P values < 0.05). Different virus has different epidemiological characteristics and distinct seasonality. The detection rate of RSV, hMPV, Inf-A were higher in Winter as 37.2%, 13.2%, 4.4%, respectively. ADV and Pinf-III were higher in summer as 2.3% and 4.6% respectively. The peak of HBoV existed in Autumn as 3.3%. The total virus detection rate showed significant inverse correlation with month average temperature (r = -0.732, P < 0.001) and a weak inverse correlation with average wind velocity was also found (r = -0.36, 0.01 < P < 0.05). The highest month total virus detection rate was from 47.6% to 84.4% when average temperature was from 3.2°C to 9.4°C and mean wind velocity was from 1.2 - 1.9 m/s. The associations of average temperature, sum of sunshine and wind velocity with RSV activity were statistical significant (r = -0.88, P < 0.001; r = -0.43, P < 0.01; r = -0.47, P < 0.01). The highest rate was from 24.3% to 58.2%, when mean temperature was from 5.3°C to 19.9°C, mean wind velocity was from 1.3 - 2.4 m/s and sum of sunshine was 61.0 to 153.4 hours. hMPV detection rate was inversely correlated with mean temperature and rain account (r = -0.43, P < 0.01; r = -0.29, P < 0.05). The rate was highest from 11.7% to 31.6% when mean temperature was from 5.3°C to 21.9°C and rain account was from 27.5 millimeter to 150.9 millimeter. Only mean temperature was positively correlated with Pinf-III (r = 0.53, P < 0.001). The rate was from 2.8% to 7.2% when mean temperature was between 11.9°C and 30.4°C. ADV detection rate was positively correlated with mean temperature and sum of sunshine, but negatively correlated with wind velocity (r = 0.35, P < 0.05; r = 0.30, P < 0.05; r = -0.32, P < 0.05). The rate was from 2.2% to 6.6% when mean temperature was between 15.9°C and 30.4°C, and sum of sunshine between 93 hours to 240.7 hours and mean wind velocity was from 1.1 - 2.8 m/s. Average temperature and relative humidity showed interactions on the detection rate of ADV (r = 0.36, P = 0.0093; r = -0.34, P = 0.016), but temperature showed higher effect on ADV detection rate. ADV detection rate was high at higher temperature (15.9 - 30.4°C) and low humidity (56% - 71%). RSV was one of the most common viruses among hospitalized children in Suzhou, and hMPV and HBoV also played an important role in respiratory tract infection of children. Different virus has different cycle and seasonality. Climatic factors, especially mean temperature, was the main factor affecting the virus prevalence.

Pulmonary exacerbations in adult patients with cystic fibrosis associated with positive viral PCR

Introduction: Studies show the prevalence of respiratory viruses in patients (pts) with cystic fibrosis (CF) and increased respiratory symptoms ranges from 13% to 52% and infection is associated with increased morbidity. Given the recent H1N1 pandemic we investigate the clinical impact of positive virus isolates in adult CF pts with an exacerbation. Method: We routinely undertake throat swabs for viral PCR in all pts starting i.v antibiotics (abx). A retrospective analysis of all pts receiving i.v abx for an exacerbation between 01/12/08 and 01/12/09 was undertaken. Pts with positive viral PCR were compared to negative controls. Exclusion criteria included pregnancy, transplant and continuous I.V. therapy. Results: A total of 42 pts (median age 26.5) had positive viral PCR (overall prevalence 9.5%), with 7 having H1N1. Negative PCR occured in 440 IV courses (189 pts). The 1st course of treatment for each patient was used as a control. Positive PCR was associated with a significantly worse baseline lung function and weight with a higher proportion of pts on enteral feed. The viral group had a higher CRP (p< 0.05), wcc (p< 0.05) and neutrophil count (p< 0.05) at the start of treatment. Viral infection was associated with a greater drop in FEV1 between pre exacerbation baseline and end of treatment in comparison to controls.

Prevalence of Respiratory Viruses in Acute Respiratory Infections in Korea, 2007

Prevalence of Respiratory Viruses in Acute Respiratory Infections in Korea, 2007

Infections by Human Coronavirus-NL in Hospitalized Children

A new human coronavirus (HCoV), HCoV-NL, was recently reported for Dutch patients with acute respiratory tract infections (ARTI). Little information is available on the incidence, clinical manifestations and epidemiologic features of HCoV-NL infections. We performed a prospective study of symptomatic (case subjects with ARTI) and asymptomatic (control subjects undergoing elective surgery) children, <or=3 years of age, hospitalized in Canada during 2 winter seasons (2001-2003), to look at the prevalence of respiratory viruses. Reverse transcription-PCR assays were used to retrospectively detect HCoV-NL and to correlate its presence with clinical symptoms. HCoV-NL was detected in nasopharyngeal aspirates from 3.0% of young children (12 of 396 children) hospitalized for treatment of ARTI (case subjects), compared with 1.7% of asymptomatic control subjects (3 of 177 children) (P = 0.6). Nine (75.0%) of the symptomatic children had mixed viral infections. The mean age and mean duration of hospitalization of case subjects were 10.1 months and 4.9 days, respectively. Final diagnoses consisted of bronchiolitis or bronchitis (9 of 12 cases), pneumonitis (1 of 12 cases) and upper respiratory tract infections (2 of 12 cases), although 2 of 3 subjects with single HCoV-NL infections had upper respiratory tract infections only. Sequence analysis of the 1a and spike genes revealed that multiple HCoV-NL strains circulated in the same geographical area in each of the 2 winter seasons. Variability was more pronounced for the spike gene, with 2 clusters of strains. HCoV-NL was not a major respiratory pathogen in Canada during our study, as shown by its low detection rate in hospitalized children with ARTI, coupled with the high frequency of additional pathogens and its occasional detection in healthy children.

Prevalence of respiratory viruses and Mycoplasma pneumoniae in sputum samples from unselected adult patients

Sputum samples from adult patients are routinely used for bacteriological tests, but not for the diagnosis of viral/mycoplasmal infections. We examined 511 sputum samples submitted for bacterial tests from patients at the Royal Adelaide Hospital. Each specimen was tested directly (and after six days of cell culture amplification) for antigens to influenza A and B, parainfluenza 1, 2 and 3, adenovirus, respiratory syncytial virus (RSV) and Mycoplasma pneumoniae. Respiratory viruses or M. pneumoniae were found in 11% of all specimens but were most common (14%) in sputa reported as containing only "oral flora". Respiratory virus or M. pneumoniae infection was significantly more common in medical patients (12%) than in surgical patients (5%), and was most common in oncology (hematology/radiotherapy) patients (25%). Influenza A and RSV were equally common in medical patients, while RSV was the most frequent isolate in oncology patients. Respiratory viral infection is an underdiagnosed condition in adults, particularly the immunocompromised, which can be successfully diagnosed by virological examination of sputum.