Objective: Influenza is considered as an emerging disease until today. The present study was undertaken to determine the prevalent genotypes of Influenza A virus in Malaysia. Methods: Influenza A virus was identified from respiratory specimens by real-time reverse transcriptase polymerase chain reaction (rRT-PCR). Phylogenetic analysis of the identified isolates was performed and genotypes were detected. Results: A total number of 505 throat swabs and nasopharyngeal aspirates were examined by rRT-PCR at Universiti Kebangsaan Malaysia Medical Centre (UKMMC) in which 65(12.87%) were positive for influenza A. The identified isolates were successfully genotyped by phylogenetic analysis. The identified influenza A genotypes were: H1N1 (42), H3N2 (20) and H5N1 (3). Conclusion: The findings indicated that 3 genotypes were circulating in Malaysia during 2011 in which H1N1 was the predominant. Results added new genotype (H5N1) identification record in Malaysia that may be added in data base of WHO and CDC.

Objective: To determine the efficacy of cell culture, immunoflourescence Assay (IFA) and real time polymerase chain reaction (rRT-PCR) in relation to diagnosis of influenza and Respiratory Syncytial Virus (RSV). Methods: Total 2781 specimens of throat swabs and nasopharyngeal aspirates were obtained from patients suspected of respiratory viruses' infections from January 2009 to December 2011 at Universiti Kebangsaan Malaysia Medical Centre(UKMMC). The specimens were processed by cell culture and immunoflurescence assay (FA) and (rRT-PCR). Results: Thirty three (1.19%) specimens were positive for influenza virus A and 42 (1.51%) were positive for RSV by cell culture and IFA. On the other hand, rRT-PCR was able to identify 189 of 505 (37.43%) specimens in which 65 were influenza A virus and 124 were RSV. Sensitivity of rRT-PCR was 100% for both influenza A virus and RSV and specificity was 88% and 77% for influenza A virus and RSV, respectively. Conclusion: rRT-PCR diagnosed respiratory viruses in shorter time with a high level of sensitivity in comparison to conventional assays - cell culture and IFA. These advantages help in managing patients by saving cost and hospitalization stay.

Human respiratory syncytial virus (RSV) is an important cause of acute respiratory tract infection in infants and young children. Phylogenetic analysis for RSV in Malaysia has not been reported before. We investigated the genetic features of RSV in respiratory specimens from March to August 2011 with molecular methods. From a total of 130 throat swab and nasopharyngeal aspirate specimens, 54 (41.5%) were positive with RSV, identified by in-house real-time reverse transcriptase polymerase chain reaction (rRT-PCR) assay. Thirty-four out of 54 (63.0%) RSV positive patients were children below two years old and two (1.4%) were adults. Phylogenetic analysis showed 39 isolates were genotype GA5, 13 genotypes GA2, one genotype GA1 and one genotype GA7. The findings indicated four genotypes of RSV circulating in the country and the predominant genotype is GA5.