And is that answer different now in our Covid world? Linda Geddes looks at the evidence and talks to the experts
As temperatures drop and November rain falls, the seasonal onslaught of coughs, sore throats and sniffles may feel inevitable, but does constant exposure to everyday infections such as colds or influenza drain us or make us stronger?
Our immune systems are often said to have memory, meaning that if an individual has previously been exposed to an infectious bug, such as a virus, specialised immune cells that remember what it looks like will continue to circulate in the blood and body fluids, ready to trigger a rapid immune response should they encounter it again. The same principle underlies vaccination – only in this case, there is no need to risk a serious infection with a virus or bacterium to develop a memory of it.
