Active Surveillance of Influenza A and Other Respiratory Viruses in Children with Influenza-like-illness in Two Seasons.

INTRODUCTION: The aim of this study was to asses the surveillance of influenza A/other respiratory viruses and risk factors in hospitalized children with the symptoms of influenza-like illness during two consecutive influenza seasons. METHODOLOGY: All children hospitalized with adiagnosis of influenza-like illness had been investigated for Influenza A and other respiratory antigens in pharengeal/nasopharyngeal secretions. RESULTS: A total of 132 hospitalized children between December 2013-May 2014 and December 2014-May 2015 were enrolled in this study. At least one respiratory virus was found to be positive by RT-PCR in 78 (59%) patients, influenza A (H3N2) was detected in only 8 (6%) patients. In 54 (41%) patients samples no respiratory viral pathogen was detected and in 70 (53%) patients, one non- influenza A virus was detected. The respiratory viral pathogens detected in decreasing rates were:RSV (n = 46, 35%), HCoV (n = 10, 7.5%), adenovirüs (n = 7, 5%), rhinovirüs (n = 6, 4.5%), HMPV (n = 5, 4%), Influenza B (n = 4, 3%) ve human Bocavirus (n = 2, 1.5%). In 10 patients, coinfection was detected, however none was with H3N2. In the H3N2 (+) group, the following risk factors were identified: age older than three years (p < 0.05), asthma history (p < 0.05) and chronic lung diseases (p < 0.05). CONCLUSION: Influenza A virus was detected in 6% of hospitalized patients with influenza-like illness. Viruses other then Influenza, especially RSV, can cause similar symptoms compatible with Influenza-like-illness.

RSV infection in Istanbul: risk factors and frequency.

INTRODUCTION: Respiratory syncytial virus (RSV) is one of the most common causes of acute respiratory infections in all age groups especially under two years. The aim of this study was to investigate the frequency and clinical features of RSV in hospitalized children under two years of age with the diagnosis of lower respiratory tract infections (LRTI) in our region. METHODOLOGY: Between September 2011- May 2013, hospitalized children aged 0-2 years with the diagnosis of viral LRTI, in which nasopharengeal secretions  were tested for the presence of the RSV antigen, were included in this prospective study. RESULTS: Among the total of 361 hospitalized children who were investigated for RSV antigen, 138 (38%) were female and 223 (62%) were male. The mean age of the group was 5,7±5,1 months (0-24 months). RSV antigen in nasopharyngeal secretions was positive in 68 (19%) of 361 patients. RSV infection was detected significantly higher in December and January (p = 0.003). RSV positivity was significantly higher in patients aged under 6 months (p=0.01), with shorter duration of breastfeeding (p = 0.02), low socioeconomic status (p = 0.02), and also born with spontaneous vaginal delivery (p = 0.007). In RSV(+) LRTI group, children were associated with severe disease than RSV (- LRTI group (p = 0.014). CONCLUSIONS: Since there is lack of data investigating the frequency and the risk factors of RSV respiratory infections in our region, the present study is important for providing new data. Furthermore, this is the second study investigating the correlation between RSV positivity and meteorological conditions in Turkey.