What are the main subtypes of influenza A?

Aug 13, 2024 ... Flu is a contagious respiratory illness caused by influenza viruses · Flu can cause mild to severe illness · Most experts believe that flu viruses ... The 1918 influenza pandemic was the most severe pandemic in recent history. It was caused by an H1N1 virus with genes of avian origin. May 1, 2023 ... Infectious Agent. Influenza is caused by infection of the respiratory tract with influenza viruses, RNA viruses of the Orthomyxovirus genus. Nov 28, 2017 ... Humans naturally infected with rhinovirus, which is the cause of the common cold, or the flu virus, which causes influenza, do not make good ... A headache is a pounding feeling in your head or neck that is triggered by pain-sensitive nerves. What are the symptoms of a cold and flu headache? What causes ... The flu is caused by a virus. Viruses are generally passed from person to person through the air when an infected person sneezes or coughs. But the virus can ... Influenza (flu) is a very contagious viral infection that affects the air passages of the lungs. It causes a high fever, body aches, a cough, and other ... Jun 14, 2022 ... Each year, millions of people suffer from seasonal influenza, which is often called the flu. Flu is a respiratory illness caused by viruses that ... Feb 12, 2018 ... We all know the symptoms of influenza infection include fever, cough, sore throat, muscle aches, headaches and fatigue. But just what causes all the havoc? Signs & Symptoms of the Flu · Fever or feeling feverish/chills · Cough · Sore throat · Sneezing · Runny or stuffy nose · Muscle or body aches · Headache ...