How might someone be naturally immune to a disease without ever coming with contact with the virus before?

Natural immunity to a disease without prior exposure can arise from genetic factors that provide a protective advantage. Some individuals may possess specific genes or immune system variations that enable them to recognize and combat pathogens more effectively. Additionally, cross-reactive immunity can occur when the immune system responds to similar antigens from other pathogens, offering some level of protection against a new virus. Lastly, maternal antibodies passed during pregnancy or breastfeeding may also contribute to innate immunity in newborns.