H3N2 influenza

About H3N2 influenza:  

• Influenza A H3N2 is a seasonal virus and the occurrence of influenza infections normally peaks during season changes.
• Symptoms- Fever, body ache, sore throat, cough, runny/blocked nose and a few shortness of breath.
• It can spread from person to person and while anyone can get infected- older, adults and younger children are at a higher risk from H3N2.
• The method of testing for H3N2 is also similar to COVID-19 testing – RTPCR.
• There is a vaccine for seasonal flu that also covers H3N2.

Seasonal influenza:

• According to WHO, seasonal influenza is an acute respiratory infection caused by influenza viruses.
• There are 4 types of seasonal influenza viruses, types - A, B, C and D. In which Influenza viruses A, B, and C can infect humans.
• Influenza A viruses are further classified into subtypes according to the combinations of the hemagglutinin (HA) and the neuraminidase (NA), the proteins on the surface of the virus.
• There are 18 different subtypes of HA, which are numbered H1 through H18. Similarly, there are 11 different subtypes of NA, numbered N1 through N11.

 

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Q1) What is Hemagglutination?

Hemagglutination is a reaction that causes clumping of red blood cells in presence of some enveloped viruses, such as the influenza virus. A glycoprotein on the viral surface, namely hemagglutinin, interacts with red blood cells, leading to the clumping of red blood cells and the formation of a lattice.

Source: All about H3N2 virus: symptoms, prevention, and cure