Applications of gold nanoparticles in virus detection

Draz, Mohamed Shehata; Shafiee, Hadi

Several strains of the genus InfluenzavirusA cause seasonal and occasional acute respiratory diseases called influenza, which is profoundly and rapidly spread in humans. Influenza is reported to affect up to 5% of adults and 20% of children of the global population each year [181, 182] . Over the past decade, the world witnessed two major influenza outbreaks caused by newly emerging InfluenzavirusA strains: H5N1 in 2003 (avian influenza), and H1N1 in 2009 (swine influenza). Both were severe enough to incite the WHO to issue a pandemic warning alert, which reached the highest level, i.e., "phase 6," for H1N1 in 2009 [21, 183] . The severity of influenza infection depends on both the virus strain and the age of the infected person. In elderly persons, influenza can result in hospitalization or death, while in younger adults, influenza-associated morbidity usually results in restricted activity, impaired work performance, and increased health care use [184, 185] . Most people with the flu recover within one to two weeks without treatment. However, serious complications usually require medications to reduce the severity and duration of infection. Some antiviral drugs, such as oseltamivir and zanamivir, can effectively treat or prevent influenza [186] . On the other hand, immunization with vaccine preparations of the most-circulating virus strains (trivalent or quadrivalent vaccines) remains the key strategy for preventing both influenza and its serious complications [187, 188] . In fact, both the treatment and management of influenza infection, either by antivirals or vaccination, depend on the influenza virus strains and the timing and severity of the infection. Therefore, the rapid and accurate testing and typing of influenza is critical for treating infection and plays an important role in public health measures.