Ülkemizden Yayınlar

Letter to the Editor.

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in infants and young children worldwide. This study was conducted to determine the prevalence of RSV among high-risk children admitted with respiratory symptoms in a developing country. This is a multicenter study conducted among children less than 24 months of age and admitted to the hospital with respiratory symptoms. The inclusion criteria included: lower respiratory tract symptoms on admission, gestational age less than 35 weeks, and admission age less than six months, or children less than 24 months of age with a diagnosis of bronchopulmonary dysplasia requiring medical treatment or intervention during the last six months or with an uncorrected congenital heart disease (other than patent ductus arteriosus). Nasopharyngeal samples were obtained with one of the three standard methods: nasopharyngeal aspirate, nasopharyngeal wash or nasopharyngeal swab. RSV antigen was determined by enzyme immunoassay using Abbott TESTPACK RSV (No. 8100/2027-16). Statistical analysis was performed using Student’s t-test and chi-square test. In this study, 332 children (135 females, 40.7%; 197 males, 59.3%) were included, and the nasopharyngeal specimens of 98 (29.5%) children were determined to be RSV-positive. There were no differences in sex, age of gestation, age of admission, family education, number of siblings and smoking at home for RSV-positive and -negative cases. Furthermore, underlying disease and duration of hospital and intensive care unit stay were similar among groups. Only otitis media was more common among RSV-positive cases. No fatality at hospital was recorded. Frozen samples revealed more negative results. Most cases presented during winter and the number of RSV-positive cases was higher in cold and economically poor areas. Premature children and children with underlying medical condition acquire RSV irrespective of other sociodemographic risk factors, and most of them are hospitalized. Thus, an RSV vaccine seems the most effective mode of protection to decrease morbidity and mortality.

AIM: The aim of this study was the evaluation of the surveillance activities for seasonal influenza in one of a sentinel city of Diyarbakir-Turkey between the years 2006 to 2009. METHOD: In Diyarbakir 10 primary health centre and 2 voluntary physician were involved to surveillance. Weekly Influenza Like Illness (ILI) were reported through Health Administration of city and each week unique nasopharyngeal swap sample were collected from one randomly selected ILI case. Nasopharyngeal swap samples were transported to Virology Laboratory of Ankara Refik Saydam Hıfzissiha Institute and virologic investigations were performed in this centre. Monthly distribution, person, place and time properties of ILI cases were shown by graphics and tabulates. Beside this forms filled for surveillance were evaluated according to their sufficiency. RESULTS: Five thousand five hundred thirty four ILI cases were reported during 2006-2007 season and 4541 cases during 2007-2008 season, 10350 cases during 208-2009 season were reported. According to monthly distribution it was determined that ILI cases apparent by the fall, increase during winter and decrease during spring. For all three seasons most of the ILI cases were aged between 1 to 4 years old. Results of virologic investigation of samples collected at 2006-2007 season were 16 Influenza B, 10 Influenza A H3, 6 adenovirus, 4 Influenza A H1, 2 Parainfluenza, and 1 RSV. At 2007-2008 season virologic results were 17 Influenza B, 3 Influenza A, 7 Influenza AH1, 10 Influenza AH3, 3 Parainfluenza. At 2008-2009 season 26 İnf B, 1 İnfAH3ve 1 RSV were the viruses found from ILI cases’ samples. CONCLUSION: The contribution of surveillance conducted in Diyarbakir city which is one of a sentinel region of Turkey was found very prior and important for National Surveillance of Influenza.

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), infl uenza virus type A and B (INF-A, INF-B), adenovirus (AdV), parainfl uenza 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 immunofl uorescence antibody (DFA) and shell vial cell culture (SVCC) methods. In DFA assay the samples were initially screened by fl uorescent-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 infl uenza 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 infl uenza 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 infl uenza viruses were the fi rst 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 infl uenza 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, infl uenza 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.

This study was conducted to investigate the respiratory viruses and subtyping of infl uenza A virus when positive by multiplex PCR in patients with fl u-like symptoms, after the pandemic caused by infl uenza A (H1N1)pdm09. Nasopharyngeal swab samples collected from 700 patients (313 female, 387 male; age range: 24 days-94 yrs, median age: 1 yr) between December 2010 - January 2013 with fl u-like symptoms including fever, headache, sore throat, rhinitis, cough, myalgia as defi ned by the World Health Organization were included in the study. Nucleic acid extractions (Viral DNA/RNA Extraction Kit, iNtRON, South Korea) and cDNA synthesis (RevertAid First Strand cDNA Synthesis Kits, Fermentas, USA) were performed according to the manufacturer’s protocol. Multiplex amplifi cation of nucleic acids was performed using DPO (dual priming oligonucleotide) primers and RV5 ACE Screening Kit (Seegene, South Korea) in terms of the presence of infl uenza A (INF-A) virus, infl uenza B (INF-B) virus, respiratory syncytial virus (RSV), and the other respiratory viruses. PCR products were detected by automated polyacrylamide gel electrophoresis using Screen Tape multiple detection system. Specimens which were positive for viral nucleic acids have been further studied by using specifi c DPO primers, FluA ACE Subtyping and RV15 Screening (Seegene, South Korea) kits. Four INF-A virus subtypes [human H1 (hH1), human H3 (hH3), swine H1 (sH1), avian H5 (aH5)] and 11 other respiratory viruses [Adenovirus, parainfl uenza virus (PIV) types 1-4, human bocavirus (HBoV), human metapneumovirus (HMPV), rhinovirus types A and B, human coronaviruses (HCoV) OC43, 229E/NL63] were investigated with those tests. In the study, 53.6% (375/700) of the patients were found to be infected with at least one virus and multiple respiratory virus infections were detected in 15.7% (59/375) of the positive cases, which were mostly (49/59, 83%) in pediatric patients. RSV and rhinovirus coinfections were the most prevalent(18/29, 62.7%) dual infections. The distribution of 436 respiratory viruses identifi ed from 375 patients were as follows; 189 (43.3%) RSV, 93 (21.4%) rhinovirus, 86 (19.8%) INF-A, seven (1.6%) INF-B, 22 (5%) PIV types 1-3, 14 (3.2%) HMPV, 11 (2.5%) HCoV, nine (2%) HBoV, and fi ve (1.2%) adenovirus. Fifty-fi ve (64%) out of 86 INF-A viruses were subtyped as hH3, 24 (27.9%) were sH1 and seven (8.1%) were hH1. Avian H5 was not detected in any samples. The overall prevalence rates of INF-A, INF-B, RSV and other respiratory viruses were 12%, 1%, 27%, and 14.6%, respectively. RSV was the most prevalent respiratory agent in pediatric (161/313, 51%) cases, while INF-A virus in adult (24/62, 38.7%) patients. Influenza viruses were detected as responsible pathogens in 13.3% (93/700) of the patients with fl u-like symptoms. Among the cases, a 1-month-old baby was infected with three virus strains (INF-A hH1+INFA sH1+HCoV OC43) and a 82-year-old patient was infected with two INF-A virus subtypes (hH3 + sH1). INF-A viruses were mostly detected (79/86) in winter period, from December to March. INF-A virus sH1, was the most prevalent subtype in fl u cases till February 2011 (22/86), after replaced by INF-A virus hH3. Beginning from February 2012, a signifi cant increase observed in the cases infected with INF-A virus subtype hH3 (39/86). In conclusion, the identifi cation and surveillance of infl uenza virus types and subtypes circulating in populations have importance both for epidemiological data and selection of vaccine strains.

Respiratory syncytial virus (RSV) infections may cause severe respiratory diseases, particularly in infants and young children. In order to determine the timing of prophylaxis, the seasonal variations of RSV had to be determined. We report the climate-related results of an epidemiological study conducted in 32 hospitals of Turkey between May 2008 and September 2010, on children <2 years of age hospitalized with lower respiratory tract infection. Information on socio-demographics, medical history, risk factors for RSV, diagnosis and severity of RSV, and hospitalization was recorded. RSV Respi-strip test kits were used to detect RSV. The meteorological data, including average monthly temperature, relative humidity (RH) and rainfalls of all cities were obtained, and the correlations between meteorological variables and RSV positivity were determined. Informed consents were obtained before the study. Overall, 3,464 children (61.9% boys), with a mean age of 6.4 months, were evaluated. RSV positivity was 16.9%. RSV peaked in January and March, in the first and second RSV seasons, respectively. When Turkey was evaluated as a whole, RSV was positively correlated with RH (p<0.001, R=0.627) and rainfalls (p=0.001, R=0.572), and was negatively correlated with temperature (p<0.001, R=-0.778). However, when the regions were evaluated separately, the rainfalls had a negative correlation with RSV activity in the Black Sea and East Anatolian regions. The current study shows the seasonal variation of RSV infections in Turkey in two consecutive RSV seasons. Country-specific viral surveillance systems are required to detect respiratory virus activities and to implement health care strategies.

The purpose of this study was to evaluate the viral frequency, seasonality, and clinical and demographic features of patients hospitalized with acute bronchiolitis. A cross-sectional, descriptive study was performed in 316 infants younger than 2 years of age who were hospitalized for acute viral bronchiolitis. Respiratory tract infection agents were investigated with polymerase chain reaction (PCR). A total of 316 infants were included in this study. Of the 316 infants, at least one respiratory tract pathogen was detected in 75% (237/316). Respiratory syncytial virus (RSV) was the most common virus identified in 127 infants (40.1%) followed by rhinovirus (n = 78, 24.6%). In this study, where viral agents were determined via PCR in patients who were followed-up due to the diagnosis of acute bronchiolitis, RSV was detected as the most common agent, as in other studies. In almost half of the RSV-positive patients, RSV was accompanied by a second or third agent.

Objective: Virus infections of the respiratory tract are among the common public health problems. They rapidly spread among people and cause significant morbidity and mortality. In this study it was aimed to investigate the distribution of respiratory tract viruses in Turkey according to the study years, months and patients’ ages between the years 2009, and 2012. Materials and Methods: Appropriate clinical samples submitted to our laboratory, were studied with “multiplex realtime polymerase chain reaction” (RT-PCR). Results: Most of the respiratory tract viruses exhibited a seasonal distribution in our country. Human rhinoviruses (HRV) were detected all throughout the year. Respiratory syncytial virus (RSV) activity begin in November and may persist in winter months up to the beginning of summer. Human metapneumovirus (HMPV) had a similiar distribution as RSV. Adenoviruses (AV) can be seen in the late autumn, winter and spring months. Human parainfluenza virus (HPIV) 3 could be seen all throughout the year while HPIV1 and HPIV2 were prevalent during the winter season. HPIV4 viruses can be detected during the autumn, winter and spring months. Coronaviruses (CoV) OC43, HKU and NL63 can be seen between November and July. CoV229E and human bocavirus (HboV) can be detected during the whole year. Enteroviruses (EV) and influenza virus A and B remain in the circulation during the autumn, winter and spring months. Conclusion: This study has presented the epidemiological data related to the seasonal distribution of the respiratory tract viruses in Turkey between 2009-2012 period. Continuous surveillance of respiratory tract viruses will help to follow up their perennial, and seasonal distribution, and detect the presence of potential epidemics and pandemics in a given area.

The aim of this study was to investigate the prevalence and seasonal distribution of respiratory viruses in pediatric patients. Nasopharyngeal swab specimens, demographic and clinical information were collected from 1240 pediatric patients aged <18 years between 2006 and 2015 in Hacettepe University Children’s Hospital. Multiplex RT-PCR (multiplex reverse transcriptase polymerase chain reaction) was performed to detect viral pathogens. A total of 1240 pediatric outpatients and inpatients who had been admitted to the hospital with symptoms of upper and lower respiratory tract infections (RTIs) were enrolled. Viruses were identified in 339 (27.3%) of cases, with the leading three viruses being respiratory syncytial virus (RSV, 74/339; 21.8%), human rhinovirus (62/339; 18.3%), and multiple viruses (56/339; 16.5%). Most of the patients were diagnosed with lower RTI (264/339; 77.8%) and antibiotics were administered to three quarters of positive patients (254/339; 74.9%). With an overall viral agent detection rate of 27.3%, the findings of the present study suggest that other respiratory pathogens, whether viral or bacterial, may also lead to hospital visits due to respiratory tract symptoms in children.

Background: Acute respiratory tract infection (ARTI) is one of the most common infections worldwide, causing significant morbidity and mortality. Objectives: This study was conducted to determine the prevalence and seasonal distribution of respiratory viruses in our region, in children and adults with a pre-diagnosis of ARTI. Methods: A total of 845 nasopharyngeal swab specimens were analyzed with the RespiFinder Smart 22 kit (PathoFinder BV, Netherlands) and the Rotor-Gene 6000 real-time PCR system. Results: At least one pathogen was detected in 612 (72.4%) of the specimens. Overall, 902 pathogens were detected; 821 (91%) were viruses and 81 (9%) were bacteria. The most commonly detected pathogens were influenza A virus (IFV-A) (n = 219), influenza B virus (IFV-B) (n=157), rhinovirus/enterovirus (n = 107), human bocavirus (HBoV) (n = 91), respiratory syncytial virus (RSV) A/B (n = 64), adenovirus (n = 56), human coronaviruses (n = 51), Mycoplasma pneumoniae (n = 49), parainfluenza viruses (n = 40), human metapneumovirus (n = 36), Bordetella pertussis (n = 15), Legionella pneumophila (n = 11), and Chlamydophila pneumoniae (n = 6), respectively. Among the 215 (25.4%) co-infected cases, IFV-A/HBoV and IFV-A/IFV-B were the most common co-infections. IFV-A was the most prevalent agent in all age groups except for children under 5 years of age, in whom RSV A/B was the most common pathogen. Approximately two thirds of the respiratory viruses were detected in early spring and winter, with peaks in January, March, and April. Conclusions: With regard to the prevalence and seasonal distribution of respiratory viruses, our epidemiological data for the 2014 - 2015 season in Istanbul showed a predominance of IFV-A infections with a peak activity in early spring. Enhanced surveillance and early detection of respiratory viral pathogens can be useful in the diagnosis, treatment, and prevention of ARTIs, and for guiding the development of appropriate public health strategies.

Respiratory syncytial virus (RSV) infections may lead to severe respiratory diseases, particularly in infants and young children. Prophylactic anti-RSV monoclonal antibodies are recommended in high-risk infants. In order to determine the timing of prophylaxis, theseasonal variations of RSV had to be determined. In the present study, we report the climate-related results of an epidemiological study conducted in 32 hospitals of Turkey between May 2008 and September 2010 on children less than two years of age hospitalized with the diagnosis of lower respiratory tract infection (LRTI). We also evaluated the correlations of meteorological variables (average monthly temperature, relative humidity and rainfall) with the percentage of RSV positivity among children hospitalized with a LRTI in Turkey as a whole, as well as among the geographic regions. Children who had used palivizumab against RSV infection and the cases in which respiratory samples could not be collected within 24 hours after hospitalization or 24 hours after emergency room (ER) or outpatient clinic administration were excluded from the study. RSV Respi-strip test kits were used to detect RSV in nasal-washing samples, nasopharyngeal aspirates, and in nasal and nasopharyngeal swabs. During the study period, 3464 children (61.9% boys), with a mean age of 6.4 months, were evaluated. According to age groups, most of the children (37.5%) were between 0-3 months old. RSV positivity was 16.9% (585 patients) in all samples. The highest RSV positivity rate was among children aged 0-3 months (27.4%; p

Syndromic diagnosis by multiplex nucleic acid amplification tests is the most practical approach to respiratory tract infections since the symptoms are rarely agent‐specific. The aim of this study was to investigate the respiratory viruses in children admitted to a university hospital with acute respiratory tract infection during the last 8 years by a multiplex polymerase chain reaction (PCR) assay. A total of 3162 respiratory samples collected from children between April 2011 and April 2018 tested by a multiplex real‐time PCR assay. Two different commercial assays were used during the study period, "AusDiagnostics/Respiratory Pathogens 12 (AusDiagnostics)" used between April 2011 and December 2015, which changed to "Fast Track Diagnostics/ Respiratory Pathogens 21 (Fast Track Diagnostics)" after January 2016 to cover more viruses. Nucleic acid extraction was done by EZ1 Advanced XL platform (QIAGEN). Respiratory pathogens detected in 1857 of the 3162 (58.7%) samples. The most prevalent viruses during the 8‐year period were rhinovirus/enterovirus (RV/EV; 36.2%), respiratory syncytial virus (RSV; 19%), and influenza virus A/B (14.7%). Rhinovirus was the main contributor to the RV/EV group as shown by the assay used during the 2016‐2018 period. RV/EV and adenoviruses detected throughout the year. Influenza virus was most frequently detected during January to March when both RSV and metapneumovirus were also in circulation. The coinfection percentage was 10.2%. Rhinovirus was the most common virus in coinfections while RSV plus rhinovirus/enterovirus were the most frequent combination. RSV and metapneumovirus showed a similar seasonal distribution to the influenza virus, which made it necessary to use a virological diagnostic assay during the influenza season.

Objective: Only a few studies have investigated the frequency and severity of respiratory syncytial virus (RSV) infections after the end of the pandemic regulations. This study aims to investigate the frequency and severity of RSV infections before, during, and after the pandemic in Turkey. Materials and Methods: Patients under 18 years of age and those who tested positive for RSV between April 2018 and March 2023 were retrospectively reviewed. All patients were divided into three groups (pre‐COVID‐19, COVID‐19, and post‐COVID‐19) according to admission date. Among inpatients, data were compared between the three groups to determine the impact of the pandemic on RSV epidemiology and clinical outcomes. Results: A total of 9567 patients were tested for RSV, of which 1073 (11.2%) were positive and included in the study. Hospitalization occurred in 447 (41.7%) patients. Inpatients were younger than outpatients (p < .000). Among the three inpatient pandemic groups, clinical outcomes were statistically significantly worse in the post‐ COVID‐19 group than in the other two groups. SpO2 was lower (p < .000), inhaled salbutamol requirement was higher (p < .000), length of stay was longer (p = .031), and ICU admission was higher (p = .023). Conclusion: Although the RSV trend changed within 2 years after the COVID‐19 outbreak, it returned to its usual seasonality last year. After the repeal of all COVID‐ 19 measures and the normal life began, the number of RSV‐positive patients and RSV‐related hospitalizations increased, and the clinical outcomes of RSV worsened. This may be a result of decreased herd immunity due to a change in society's attitude toward epidemic diseases.

The epidemiology of respiratory infections may vary depending on factors such as climate changes, geographical features, and urbanization. Pandemics also change the epidemiological characteristics of not only the relevant infectious agent itself but also other infectious agents. This study aims to assess the impact of the COVID-19 pandemic on the epidemiology of viral respiratory infections in children. We retrospectively reviewed the medical records of children aged ≤18 years with laboratory-confirmed viral respiratory infections other than COVID-19 from January 2018 to March 2023. Data on demographic characteristics, month and year of admission, and microbiological results were collected. During the study period, 1,829 respiratory samples were sent for polymerase chain reaction testing. Rhinovirus was identified in 24% of the patients, mixed infections in 21%, influenza virus in 20%, and respiratory syncytial virus in 12.5%. A 38.6% decrease in viral respiratory infections was observed in 2020, followed by a 188% increase in 2021. The respiratory syncytial virus was significantly more common in the post-pandemic period (13.8%) compared to the prepandemic period (8.1%), but no seasonal shift in respiratory syncytial virus infection was observed. There was also a yearly increase in influenza infections in the post-pandemic period compared to the pre-pandemic period. After the COVID-19 pandemic, the frequency of parainfluenza virus infections increased during the summer months, and this finding provides a new contribution to the existing literature.

Introduction: We aimed to determine the epidemiological change in influenza and other respiratory tract viruses isolated from patients with nasopharyngeal swab samples in our hospital during the COVID-19 period. Methods: We investigated nasopharyngeal swabs for respiratory viruses between March 2020 and February 2021 during the first year of pandemic in Turkey.We used QIAStat Dx Respiratory panel(Qiagen, Germany) in QIAStat Dx (Qiagen, Germany) for detection of respiratory viruses between March 2020 and February 2021. Respiratory panel kit included influenza A, B, influenza A H1N1, rhinovirus/enterovirus, parainfluenza (PIV) 1,2,3,4, coronaviruses (CoVs) NL 63, 229E, OC43 and HKU1, human metapneumovirus (MPV) A/B, bocavirus, respiratory syncytial virus (RSV) A/B and adenovirus. Results: We retrospectively analyzed the results of 319 nasopharyngeal swab samples. The average age of 199 (62.4%) male and 120 (37.6%) female patients between the ages of 0–92 was 16 years. We found that 101 (31.7%) samples were positive for viruses. Rhino/enteroviruses were the most common viruses in all age groups. Influenza positivity rate during the first year of pandemic declined to 2.3% from 17.3% among the previous year. MPV infection activity did not change during the pandemic. Discussion: According to our findings we argue that epidemiology of respiratory viruses has changed during the pandemic period. Despite the current clinical focus on the COVID-19 pandemic, clinicians should keep in mind that rhino/enterovirus and MPV infections may mimic COVID-19 and respiratory infections should be differentially diagnosed with rapid multiplex kits containing SARS-CoV-2, rhino/enterovirus and MPV.

Introduction: Viruses are responsible for two-thirds of all acute respiratory tract infections. This study aims to retrospectively detect respiratory tract viruses in patients from all age groups who visited the hospital.Methodology: A total of 1592 samples from 1416 patients with respiratory tract symptoms were sent from several clinics to the Molecular Microbiology Laboratory at Gazi University Hospital from February 2016 to January 2019. Nucleic acid extraction from nasopharyngeal swabs, throat swabs or bronchoalveolar lavage (BAL) samples sent to our laboratory was done using a commercial automated system. Extracted nucleic acids were amplified by a commercial multiplex-real time Polymerase Chain Reaction (PCR) method, which can detect 18 viral respiratory pathogens.Results: Among 1592 samples, 914 (57.4%) were positive for respiratory viruses. The most prevalent were rhinovirus (25.2%) and influenza A virus (12.1%), the least prevalent was the bocavirus (2.6%). Rhinovirus was the most detected as a single agent (21.2%, 194/914) among all positive cases, followed by coronavirus (9.3%, 85/914). The detection rates of coronavirus, human adenovirus, respiratory syncytial virus A/B, human parainfluenza viruses, human metapneumovirus-A/B, human parechovirus, enterovirus and influenza B virus were 9.9%, 8%, 7.7%, 5%, 3.4%, 3.1%, 3%, and 2.8%, respectively.Conclusions: The most detected viral agents in our study were influenza A virus and rhinovirus. Laboratory diagnosis of respiratory viruses is helpful to prevent unnecessary antibiotic use and is essential in routine diagnostics for antiviral treatment. Multiplex Real-time PCR method is fast and useful for the diagnosis of viral respiratory infections.

Objective: Lower respiratory tract infections of predominantly viral origin disproportionately affect infants and children, and respiratory syncytial virus (RSV) is a primary pathogen in this age group. This study employed rapid testing methodologies to detect RSV infection among hospitalized pediatric patients, providing insights into its prevalence, epidemiological, and clinical characteristics, and impact on mortality and morbidity. Material and Methods: This study, conducted between September 1, 2009 and April 30, 2011, targeted infants aged 0-24 months who were hospitalized with lower respiratory infections at the Pediatric Clinic of University of Health Sciences Turkey, Kartal Dr. Lütfi Kırdar Training and Hospital. Upon admission, each patient underwent a comprehensive medical history evaluation, which included assessments for prematurity, congenital heart disease, recurrent infectious diseases, reactive respiratory system disease, and immune system disorders. Additionally, physical examination, routine tests, and nasopharyngeal swab samples were collected. RSV detection was performed using the Respi-Strip kit. Results: Among the 311 patients included in the study, 182 (58%) were male, and RSV was detected in 110 (35%) patients. Of those who tested positive for RSV, 72 (65%) were male. A significant prevalence of RSV infection was observed among patients aged 6 months. The incidence of RSV was notably higher in December, January, and March. A statistically significant negative correlation was found between the duration of breastfeeding and the likelihood of RSV infection. RSV positivity was significantly associated with temperatures below 10 °C and relative humidity levels exceeding 60%. Additionally, a significant association was noted between RSV infection, the presence of clinically diagnosed otitis media, and chest retraction.Conclusion: Regular screening for RSV is essential for early diagnosis, enabling targeted therapy, and improving patient outcomes. This proactive strategy may reduce morbidity, mortality, and economic impacts. Further epidemiological and clinical research on RSV transmission is crucial for protecting populations at risk, enhancing disease prevention measures, optimizing isolation protocols, and developing novel treatment options.

Introduction: This study aimed to evaluate the frequency and typing of viral and bacterial pathogens in patients with a preliminary diagnosis of respiratory tract infection during the epidemic period in Türkiye. Material and Method: The study included the respiratory pathogen analysis results of 215 patients aged 0–17 years admitted to the Pediatrics Department of Kütahya Health Sciences University Evliya Çelebi Training and Research Hospital between October 2022 and March 2023 with symptoms of respiratory tract infections. Twenty-three viruses and six bacteria in the respiratory panel were studied using multiplex real-time PCR. Samples were obtained from a nasopharyngeal swab in non-intubated patients and tracheal aspiration material in intubated patients. Results: While 92.1% of the patients were positive for one or more agents, no agent was detected in 7.9%. Among the positive results, the rate of the single pathogen was 27.3% (n=54), while the rate of multiple pathogens was 72.7% (n=144). Respiratory syncytial virus was the most common viral agent with a rate of 23.3% and Adenovirus with a rate of 19.1%, while Haemophilus influenzae (48.8%) and Streptococcus pneumoniae (29.3%) were the most common bacterial agents. Conclusion: In this study, viral and bacterial pathogens have been studied intensively in children. Simultaneous, rapid, and sensitive detection of these agents is essential in preventing unnecessary antibiotic use and infection control. This is also important in terms of reducing mortality and morbidity rates

Human respiratory syncytial virus (HRSV) is most important viral respiratory pathogen of acute lower respiratory tract infections in infants and young children worldwide. The circulating pattern and genetic characteristics in the HRSV attachment glycoprotein gene were investigated in Turkey during six consecutive seasons from 2009 to 2015. HRSVA was dominant in the all epidemic seasons except 2011-2012 season. Partial sequences of the HVR2 region of the G gene of 479 HRSVA and 135 HRSVB were obtained. Most Turkish strains belonged to NA1, ON1, and BA9, which were the predominant genotypes circulating worldwide. Although three novel genotypes, TR-A, TR-BA1, and TR-BA2, were identified, they were not predominant. Clinical data were available for 69 HRSV-positive patients who were monitored due to acute lower respiratory tract illness. There were no significant differences in the clinical diagnosis, hospitalization rates, laboratory findings and treatment observed between the HRSVA and HRSVB groups, and co-infections in this study. The major population afflicted by HRSV infections included infants and children between 13 and 24 months of age. We detected that the CB1, GB5, and THB strains clustered in the same branch with a bootstrap value of 100%. CB-B and BA12 strains clustered in the same branch with a bootstrap value of 65%. The BA11 genotype was clustered in the BA9 genotype in our study. The present study may contribute on the molecular epidemiology of HRSV in Turkey and provide data for HRSV strains circulating in local communities and other regions worldwide.

Aim: Viruses including respiratory syncytial virus, parainfluenza virus, rhinovirus are the primary etiologic agents in acute lower tract infections in neonates. We aimed to evaluate the clinical and demographic characteristics of newborns with acute lower tract infections. Material and Method: Data was recorded from patients' medical records admitted between January 2013 and April 2016. Results: The study population consisted of 43 neonates (19 girls, 24 boys). Mean gestational age and birthweight were 32 ± 4.4 weeks and 1735 ± 820 g, respectively. On admission, mean postnatal day and postmenstrual ages were 61 ± 48 days and 41 ± 4.3 weeks. Respiratory syncytial virus (n:8), rhinovirus (n:3), parainfluenza-3 virus (n:3) and adenovirus (n:3), respiratory syncytial virus and parechovirus (n:1), respiratory syncytial virus and adenovirus (n:1), rhinovirus and human bocavirus (n:1) were detected by polymerase chain reaction 20 patients in total. Siblings in the house (n:31), viral infection in the family (n:23), insufficient breastfeeding (n:15), bronchopulmonary dysplasia (n:13), siblings attending school (n:10) and being twin or triplet (n:7) were leading risk factors. Median hospital stay was 9 (1-60) days. Prematurity, fever, rales, respiratory support and feeding difficulty were statistically more common in polymerase chain reaction positive patients. Patients with the respiratory syncytial virus had higher gestational age, birth weight, less respiratory distress syndrome, surfactant use and patent ductus arteriosus, and lower postnatal day on admission than patients with other viruses (p

Objective: Several public health measures were introduced to reduce viral transmission and disease spread at the beginning of the COVID-19 pandemic. These measures had the potential to impact the transmission of other respiratory viruses. In September 2021, schools started face to face in and an increase in viral respiratory infections was observed. This study aims to determine the distribution and clinical features of viral agents in this period when complete face-to-face education was started for the first time in Turkey. Material and Methods: Diagnosis and clinical data of the pediatric patients who were tested for respiratory viral infections between October 1, 2021-January 1, 2022 were retrospectively retrieved from hospital records. Viral agents detected by polymerase chain reaction (PCR) in the nasopharyngeal aspirate samples obtained at the first application of the patients during the pandemic period were investigated. Results: There were 404 patients who were diagnosed with respiratory tract infections and tested for respiratory viruses. The leading viral agents in children who applied to our center between October and December 2021 were COVID-19 (32.7%), multiple viral agents (23.9%), RSV (15.3%) and rhinovirus (8.7%). 43.8% of patients diagnosed with RSV needed hospitalization. Conclusion: Our study shows that after complete face-to-face education and, the viral diversity is observed again in this winter period like before the pandemic. The high rate of hospitalization in RSV cases was remarkable.

Objectives: This retrospective study was aimed to identify upper respiratory tract infection (URTI) pathogens in patients admitted to Kafkas University Medical Faculty Hospital between July 2023 and August 2024. Methods: Nasopharyngeal swab samples from 1565 patients were analysed using the Multiplex Real-Time PCR (MRTPCR) technique. Patient demographics, the month/season of hospital visits, and results of the respiratory agent tests were obtained from hospital archives and subjected to necessary statistical analyses. Chi-square and One-way ANOVA tests were used to analyse categorical and numerical data, respectively by SPSS v21.0. Results: The data showed that 37.7% of the patients tested positive for at least one pathogen, while 62.3% were negative. The most frequently detected viral agents were Influenza B (34.3%), Influenza A (15.7%), and SARS-CoV-2 (14.4%). Streptococcus pyogenes was the most common bacterial pathogen (9.3%). Co-infection was observed in 9.14% of cases, with the most common combination being INF-B and INF-A. The seasonal distribution indicated that 40.3% of the positive cases occurred in the winter months (December 2023 - February 2024), and 39.1% in the spring (March - May 2024). Conclusion: This retrospective study provides important epidemiological data on the identification and distribution of URTI pathogens in the region, contributing to the development of accurate approaches for diagnosis and treatment of infections.

Background. We aimed to evaluate the effects of public health measures taken during the COVID-19 pandemic on respiratory viruses. Methods. The study was conducted between February 1, 2021 and December 1, 2022. Patients aged 1 month to 18 years hospitalized for infectious diseases were tested for SARS-CoV-2 and respiratory viruses by multiplex PCR. Results. Of the total 1173 patients, 56.2% were male and 43.8% were female, and 47.5% of the patients were under 24 months of age. The viruses detected were SARS-CoV-2 31.9%, human rhinovirus/enterovirus 19.4%, respiratory syncytial virus (RSV) 9.3%, parainfluenza virus 7%, adenovirus 6%, seasonal coronavirus 5.2%, bocavirus 3.8%, influenza 3.1%, and metapneumovirus 2.8%. Among the patients, 386 were hospitalized with lower respiratory tract infections, 238 with upper respiratory tract infections, 202 to evaluate fever etiology, 111 with acute gastroenteritis and 236 with other diagnoses. Of these patients, 113 were admitted to the intensive care unit. Intensive care unit admission rates were statistically significantly higher for bocavirus and RSV, in those hospitalized between July 1, 2021 and July 1, 2022 (first period when schools were held full-time face-toface at all grades) and in children aged 1-24 months. Conclusions. Public health measures taken during the COVID-19 pandemic have affected the seasonal distribution of respiratory viruses and the severity of illness in children.

BACKGROUND: Non-pharmaceutical interventions (NPIs) applied to limit the SARS-CoV-2 pandemic also affect the circulation and seasonal characteristics of other respiratory viruses. OBJECTIVES: Assess the impact of NPIs on the spread and seasonal characteristics of non-SARS-CoV-2 respiratory viruses and examine viral respiratory co-infections. DESIGN: Retrospective cohort SETTING: Single center in Turkey. PATIENTS AND METHODS: Syndromic multiplex viral polymerase chain reaction (mPCR) panel results of patients admitted to the Ankara Bilkent City Hospital with symptoms of acute respiratory tract infection between April 1, 2020 and October 30, 2022 were evaluated. Two study periods before and after 1 July 2021, when the restrictions were discontinued, were statistically analyzed and compared to determine the effect of NPIs on circulating respiratory viruses. MAIN OUTCOME MEASURES: Prevalence of respiratory viruses as determined by syndromic mPCR panel. SAMPLE SIZE: 11300 patient samples were evaluated. RESULTS: At least one respiratory tract virus was detected in 6250 (55.3%) patients. Of these, at least one respiratory virus was detected in 5% in the first period (between April 1, 2020 and June 30, 2021, when NPIs were applied), and in 95% in the second period (between July 1, 2021 and October 30, 2022, when NPIs were relaxed). After the removal of NPIs, there was a statistically significant increase in hRV/EV, RSV-A/B, Flu A/H3, hBoV, hMPV, PIV-1, PIV-4, hCoV-OC43, PIV-2 and hCoV-NL63 (P

OBJECTIVE: Respiratory viral diseases are common in children. A viral diagnostic test is necessary, because COVID-19 shows signs and symptoms similar to those of common respiratory viruses. The article aims at analyzing the presence of respiratory viruses that were common before the pandemic in children who were tested for suspected COVID-19, and is also concerned with how common respiratory viruses were impacted by COVID-19 measures during the second year of pandemic. PATIENTS AND METHODS: Nasopharyngeal swabs were examined to detect the presence of respiratory viruses. The respiratory panel kit included SARS-CoV-2, influenza A and B, rhinovirus/enterovirus, parainfluenza 1, 2, 3 and 4, coronaviruses NL 63, 229E, OC43, and HKU1, human metapneumovirus A/B, human bocavirus, respiratory syncytial virus (RSV) A/B, human parechovirus, and adenovirus. Virus scans were compared during and after the restricted period. RESULTS: No virus was isolated from the 86 patients. SARS-CoV-2 was the most frequently observed virus, as expected, and rhinovirus was the second, and coronavirus OC43 was the third. Influenza viruses and RSV were not detected in the scans. CONCLUSIONS: Influenza and RSV viruses disappeared during the pandemic period and rhinovirus was the second most common virus after the CoVs during and after the restriction period. Non-pharmaceutical interventions should be established as a precaution to prevent infectious diseases even after the pandemic.

Aim: Respiratory viruses significantly impact public health, contributing to high morbidity and mortality rates in both children and adults. This study evaluates the distribution and incidence of respiratory tract viruses in our hospital from 2019 to 2022, focusing on changes post-COVID-19 pandemic. Material and Methods: Utilizing molecular methods, we analyzed nasopharyngeal swabs with the FTD Respiratory Pathogens 21 kit and the QIAStat Dx Respiratory Panel kit at Istanbul Faculty of Medicine. A total of 1186 viruses were detected in 2488 samples (47.6% of the total) examined with the FTD Respiratory Pathogens 21 kit between 2019 and 2022. Results: It was determined that the detection rates were 52.8% in 2019, 44.3% in 2020, 50.0% in 2021, and 40.0% in 2022. Notable changes in prevalence were observed for pandemic influenza A (IAV-H1N1pdm2009), parainfluenza virus (PIV)-3, rhinovirus (RV), and respiratory syncytial virus (RSV)-A/B (p < 0.05). RV consistently showed the highest detection rates across all years (17.6% to 7.9%). Additionally, 1276 viruses were detected in 1496 samples using the QIAStat DX kit, with 91.3% positivity in 2021 and 78.6% in 2022, highlighting the kit’s effectiveness in rapid diagnosis. Conclusions: This study enhances understanding of respiratory virus epidemiology during and after the pandemic, emphasizing the need for ongoing surveillance and strategic public health measures to address the evolving landscape of respiratory infections.

Objective: To evaluate the distribution and characteristics of respiratory viral pathogens and to assess the epidemiological data, clinical features, and prognoses of infected children in a pediatric emergency department during the COVID-19 pandemic. Materials and Methods: Between September 1, 2020, and April 30, 2021, patients aged between 0 and 18 years arrived at the pediatric emergency department and were tested by nasopharyngeal/tracheal specimen polymerase chain reaction for both SARS-CoV-2 and other viral respiratory pathogens. Demographics, symptoms, laboratory and radiologic investigations, respiratory viruses detected by PCR, presence of co-infection and co-infecting viruses, need for respiratory support, hospitalization, length of hospital stay, and prognosis were recorded. Results: There were 327 patients for whom PCR tests were performed and 118 (36.0%) of them had positive results for SARS-CoV-2 and/or other respiratory viruses. Rhinovirus was the most commonly detected pathogen with 74 (62.7%) cases, followed by enterovirus with 38 (32.2%) and adenovirus with 20 (16.9%) cases. There was no detection of influenza virus or respiratory syncytial. SARS-CoV-2 PCR results were positive in 14 (11.9%) cases and there was only 1 coinfection of SARS-CoV-2 occurring together with rhinovirus. For 43 (36.4%) patients, there was co-infection, and among co-infections, the most common was that of rhinovirus and enterovirus, seen in 37 (86.0%) cases. Conclusion: A decrease was observed in the positivity rate of respiratory viral pathogens, while no cases of influenza virus or respiratory syncytial virus were observed in our study. Circulating viruses may change due to multifactorial approaches during the COVID-19 pandemic.

The aim of this study is to determine the causative respiratory viruses (RVs) in hospitalized children due to acute respiratory tract infections (RTIs) in the 2019-2020 fall-winter season, before the COVID-19 pandemic, examine the clinical and laboratory findings, discuss the prevention strategies during the ongoing pandemic process, and contribute to the literature by providing data just before the pandemic. Aged between one month-18 years of patients who were admitted to Sivas Cumhuriyet University Hospital and hospitalized due to acute RTIs between September 1, 2019, and March 1, 2020, and had a RVs multiplex PCR panel were analyzed retrospectively. 139 patients were evaluated. At least one viral pathogen was detected in 105 (75.5%) patients. 5 patients (3.59%) had co-infection. The most common viruses detected were Influenza A (H1N1) (21.8%), Influenza B (20.9%), Rhinovirus (RV) (18%) and, Respiratory Syncytial Virus (RSV) (17.3%). RSV was the most common viral agent under the age of 1. 52 patients (37.4%) were followed up in Pediatric Intensive Care Unit (PICU), and the most common viral pathogens isolated in PICU were RSV (17.3%), RV (17.3%) and Bocavirus (HBoV)(9.6%). RV and HBoV patients needed high levels of oxygen and respiratory support. Unnecessary antibiotic use and morbidity can be reduced by detecting the viral agent in the early period with the PCR method. RSV prophylaxis and influenza vaccination should be continued uninterruptedly for children at risk groups during the COVID-19 pandemic process.

Respiratory syncytial virus (RSV) is one of the most common viruses to infect children worldwide and is the leading cause of lower respiratory tract illness (LRI) in infants. This study aimed to conduct a systematic review by collecting and reviewing all the published knowledge about the epidemiology of RSV in the Middle East and North Africa (MENA) region. Therefore, we systematically searched four databases; Embase, Medline, Scopus, and Cochrane databases from 2001 to 2019 to collect all the information related to the RSV prevalence, genotype distribution, and seasonality in children in MENA region. Our search strategy identified 598 studies, of which 83 met our inclusion criteria, which cover the past 19 years (2000–2019). Odds ratio (OR) and confidence interval (CI) were calculated to measure the association between RSV prevalence, gender, and age distribution. An overall prevalence of 24.4% (n = 17,106/69,981) of respiratory infections was recorded for RSV. The highest RSV prevalence was reported in Jordan (64%, during 2006–2007) and Israel (56%, 2005–2006). RSV A subgroup was more prevalent (62.9%; OR = 2.9, 95%CI = 2.64–3.13) than RSV B. RSV was most prevalent in children who were less than 12 months old (68.6%; OR = 4.7, 95%CI = 2.6–8.6) and was higher in males (59.6%; OR = 2.17, 95%CI = 1.2–3.8) than in female infants. Finally, the highest prevalence was recorded during winter seasons in all countries, except for Pakistan. RSV prevalence in the MENA region is comparable with the global one (24.4% vs. 22%). This first comprehensive report about RSV prevalence in the MENA region and our data should be important to guide vaccine introduction decisions and future evaluation.

Objective: Primary preventive nonpharmaceutical interventions were introduced to reduce viral transmission and disease spread at the beginning of the COVID-19 pandemic. Therefore, herein, we aimed to determine and assess the impact of the nonpharmaceutical interventions on bronchiolitis and varicella infection rates in the pediatric population during the pandemic compared to the previous four years. We also aimed to evaluate which viruses cause viral respiratory tract infections during the pandemic period. Material and Methods: Diagnosis and laboratory data of the patients who were one month to 18 years of age were retrospectively retrieved from hospital records. The distribution of the number of patients with bronchiolitis and chickenpox diagnoses was shown monthly between January 2016 and December 2020. Viral agents detected by polymerase chain reaction (PCR) in the nasopharyngeal aspirate samples obtained at the first application of the patients during the pandemic period were investigated. Results: The data of 2.254.877 pediatric patients admitted to our hospital from January 2016 to December 2020 were examined. There were 38.458 bronchiolitis and 954 chickenpox cases reported both as inpatients and outpatients. There was a 85.6% decrease in the rate of bronchiolitis compared to previous years, and chickenpox peak was not observed in the pandemic period. Rhinovirus was found to be the most common etiologic agent of bronchiolitis during the pandemic period and Respiratory Syncytial Virus (RSV) came second. A significant decrease in the frequency of influenza was also observed. Conclusion: Our study reveals that the measures which curtail social life and prioritize social distancing prevent the spread of viral infections. It has also shown that there is an increase in the frequency of Rhinovirus infection during the pandemic period.

Objective: This study aimed to report the respiratory tract viruses we detected in the respiratory polymerase chain reaction (PCR) samples taken from patients admitted to the Pediatric Emergency Service with suspicion of coronavirus disease-2019 (COVID-19) in the early stages of the pandemic, in addition to the clinical course, and laboratory features of the disease caused by these identified respiratory tract viruses. Method: All upper respiratory tract PCR samples were taken simultaneously from patients suspected of having COVID-19 disease. All pediatric patients who came to the Pediatric Emergency Department with suspicion of COVID-19 disease between March and June 2020 were included in the study. We retrospectively compared the laboratory findings, clinical manifestations, and primary outcomes of the children aged between 1 month and 18 years infected with respiratory viruses (RVs) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus. Results: Fifty-eight pediatric patients were tested. SARS-CoV-2 virus was detected in 27 (46.6%) patients and other RVs in 31 (53.4%) patients. The detection rate of SARS-CoV-2 was significantly higher in the older age group of children (p