Influenza (or flu) is a huge global problem, one billion people—1/7th of the world’s population get infected with it each year. The virus does not only infect people it also infects many different animals including chickens and pigs and can have devastating effects on farms where these animals are raised. Our body has evolved ways (called the immune response) to kill the influenza virus if we are infected with it and to stop us getting reinfected with the same virus. Through the power of vaccines, we can harness the immune response to protect us against influenza. The problem with the influenza virus is that it is sneaky and can change its coat, so our body does not recognize it. Current research is looking at ways to overcome this sneaky virus and reduces the number of people who get sick from influenza.