%0 Journal Article
%T Comparison of Direct Fluorescence Assay and Real-Time RT-PCR as Diagnostics for Respiratory Syncytial Virus in Young Children
%A Caroline F. Shafik
%A Emad W. Mohareb
%A Fouad G. Youssef
%J Journal of Tropical Medicine
%D 2011
%I Hindawi Publishing Corporation
%R 10.1155/2011/781919
%X Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infections in children worldwide. Early detection of RSV is critical to initiate proper care. Two methods, the direct fluorescence assay (DFA) and the real-time reverse-transcription polymerase chain reaction (rt-RT-PCR), that are used for RSV detection were compared. A total of 451 nasopharyngeal aspirates from children 5 years of age or less were tested for RSV using both methods. The overall prevalence rate of the RSV among the children was 23.7% with a significantly higher prevalence among children under the age of 6 months of age when compared to other age groups. The sensitivity of DFA in comparison to rt-RT-PCR was highest (86%) during the first 3 days of symptoms onset and decreased gradually till it reached 65% after the first week. The specificity of DFA in comparison to rt-RT-PCR ranged between 99 and 100% irrespective of the date of collection. We concluded that, although the rt-RT-PCR is more sensitive for RSV detection, the DFA offers a reliable point-of-care alternative detection method especially during the first few days of illness. 1. Introduction Respiratory syncytial virus (RSV) is a negative sense single-stranded RNA virus belonging to Pneumovirus genus, subfamily Pneumovirinae. RSV is considered a major cause of severe lower respiratory tract infections in children less than two years of age worldwide [1]. Morbidity and mortality are greatly increased in children with bacterial coinfections or superinfections [2]. Therefore, early detection of the virus is a critical step in the initiation of proper care, and the prevention of further spread of the virus in public places such as schools and health care facilities. Direct Fluorescence assay (DFA) is a conventional method that is frequently used in the clinical setting for the detection of respiratory viruses including RSV. However, nucleic acid detection methods have proven to be more sensitive for RSV detection [3]. Some countries, particularly developing countries, cannot afford to use nucleic acid detection methods within hospital laboratories due to high cost and lack of technical expertise. In this study, we compared the sensitivity and specificity of the DFA against real-time reverse transcriptase polymerase chain reaction (rt-RT-PCR) as a point-of-care method for RSV detection. Comparison was also made between both assays in relation to the days after onset of symptoms. 2. Materials and Methods Four hundred and fifty one specimens were collected between December, 2006 and November, 2007 from
%U http://www.hindawi.com/journals/jtm/2011/781919/