From the time of conception to the time of death, people are vulnerable to acquiring immortal pathogens and parasites. The more immortal pathogens and parasites a person acquires and the higher the cumulative infectious burden, the more likely a chronic disease will develop. Whether the immortal infections and parasites are diagnosed and treated, whether the immortal infections and parasites are diagnosed and treated at the point of an acute or chronic infection, and how the immortal infections and parasites are treated, impact the future development of chronic disease.