Our “killer” cells’ role in life-long flu vaccine

Killer immune cells that can fight all strains of influenza virus provide the potential for a universal, one-shot flu vaccine. In the battle against the flu, our ‘killer’ immune cells are like the body’s border control. These microscopic killers are white blood cells that can maintain a memory of previous exposure to a flu strain. And if they recognise an invader, these cells start an immune response to target and kill off the virus – stopping the infection. But the problem is that there are three types of influenza virus that can infect humans – strains A, B and C. They circulate in the human population globally, and mutate every flu season. And the virus is smart. It mutates in order to hide from our immune system, which means every year we have to have an annual flu vaccination against these new strains. These mutations can also occur when the virus transmits between humans...