Category FAQs Search : Health
Question: Diagnosis of seasonal influanze
Answer: The majority of cases of human influenza are clinically diagnosed. However, during periods of low influenza activity and outside of epidemics situations, the infection of other respiratory viruses e.g. rhinovirus, respiratory syncytial virus, parainfluenza and adenovirus can also present as Influenza-like Illness (ILI) which makes the clinical differentiation of influenza from other pathogens difficult.
Collection of appropriate respiratory samples and the application of a laboratory diagnostic test is required to establish a definitive diagnosis. Proper collection, storage and transport of respiratory specimens is the essential first step for laboratory detection of influenza virus infections. Laboratory confirmation of influenza virus from throat, nasal and nasopharyngeal secretions or tracheal aspirate or washings is commonly performed using direct antigen detection, virus isolation, or detection of influenza-specific RNA by reverse transcriptase-polymerase chain reaction (RT-PCR). Various guidance on the laboratory techniques is published and updated by WHO. (3)
Rapid influenza diagnostic tests (RIDTs) are used in clinical settings, but they have lower sensitivity compared to RT-PCR methods and their reliability depends largely on the conditions under which they are used.
(Source: World Health Organization (WHO), 20 Feb 2020)
Source Link: https://www.who.int/en/news-room/fact-sheets/detail/influenza-(seasonal)