Reverse Transcription Polymerase Chain Reaction (RT-PCR) as an influenza diagnostic test among children in Yogyakarta

Background Influenza virus type A, especially H5N1 subtype or avian influenza, is a highly pathogenic agent that causes epidemic in the world with high mortality. Most cases are preschool and school children. Anti -viral drug is effective when given at early phase. The gold standard for the diagnosis of influenza is viral culture, which takes 2 to 10 days. A rapid and accurate diagnostic test is needed to control further viral infection. Objective To determine the accuracy of RT-PCR as a diagnostic test for children with influenza compared with viral culture. Methods A cross-sectional study was conducted in primary health cares of Jetis I, Godean I, II and Dr Sardjito Hospital Yogyakarta between January 2005 and May 2007. The specimens, taken by trained health personnel, were collected from both anterior nares and throat of children aged from birth to 14 years who met the eligibility criteria, then were stored in a frozen extraction tube and sent to Jakarta for RT-PCR and viral culture as the gold standard. Results There were 347 children enrolled in this study. Influenza infection was confirmed in 63 children (18.2%). There were 24 children with H3N2 subtype of influenza virus, 13 children with HINT subtype, and one child with H5N1 subtype. The sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio of RT-PCR test were 89%, 90%, 67%, 97%, 9, 3, 0, and 12 respectively. Conclusions RT-PCR is accurate enough as influenza diagnostic test in children.