Molecular diagnosis of H1N1 virus

BackgroundInfluenza A viruses are medically significant pathogens responsible for higher mortality and morbidity throughout the world. Swine influenza is known to be caused by influenza A subtypes H1N1, H1N2, and H3N2, which are highly contagious, and belongs to the family Orthomyxoviridae. Efficient and accurate diagnosis of influenza A in individuals is critical for monitoring of a constantly evolving pandemic. A rapid result is important, because timely treatment can reduce disease severity and duration. Rapid antigen tests were among the first-line diagnostic tools for the detection of pandemic H1N1 (2009) virus infection during the initial outbreak. Current study focuses on the significant approach of the usage of molecular method utilizing real-time PCR for the detection of type A influenza virus (H1N1 subtype) in humans.MethodsA total of 2000 mixed nasal/throat swab specimens collected in commercial viral transport from Apollo hospitals, Hyderabad were submitted to Institute of Preventive Medicine for molecular testing by reverse transcriptase polymerase chain reaction (RT-PCR) from 2009 to 2015 from its affiliated primary care clinics.ResultsAmong the 2000 samples collected, 700 samples were positive for Human Inf A, swine Inf A, and Swine Inf H1 (fourth table in the article). One thousand two hundred samples were negative for Human Inf A, swine Inf A, and Swine Inf H1, and 100 samples were positive for Influenza A only.ConclusionThe molecular testing of H1N1 patients helped the clinicians in timely diagnosis and treatment of these patients during the pandemic surveillance. The RT-PCR test has higher sensitivity and specificity; hence it is considered to be the best tool to use during the pandemic surveillance, as compared to the any other commercial antigen-based tests, which show a variable performance, with the sensitivities of tests from different manufacturers ranging from 9 to 77%.