The TelegraphScientists believe common colds can boost the immune system against Covid. They discovered that some people are immune to the virus, and have never been infected. University College London (UCL), discovered that some people are naturally protected against Covid. They can fight off infection by using their pre-existing memory cells. T-cells can remember previous infections and circulate throughout the body looking out for intruders. They can activate other parts of the t and kill cells.
