We are conceived, we get infected, our immune systems wage an ongoing war with immortal pathogens, and the battle evolves over time into a chronic disease. The same pathogen can cause more than one disease, and can cause different diseases in different patients.  Different pathogens can cause the same disease.  Chronic infections and co-infections (bacterial, viral and parasitic), can combine to accelerate the development and severity of disease. Acute influenza in the presence of a chronic infection, can trigger heart attack and stroke in the ensuing months.

Underlying chronic infections and the overall infectious burden likely play a role in the severity and prognosis in covid-19 patients.  High throughput sequencing technology can test for many pathogens in a patient at the same time; and the implementation of high throughput technology in medical practice will benefit covid-19 patients and all patients with chronic disease.