Pre-symptomatic is the adjective categorising the time periods during which the medical conditions are asymptomatic.
Subclinical and paucisymptomatic are other adjectives categorising either the asymptomatic infections (i.e., subclinical infections), or the psychosomatic illnesses and mental disorders expressing a subset of symptoms but not the entire set an explicit medical diagnosis requires.
An example of an asymptomatic disease is cytomegalovirus (CMV) which is a member of the herpes virus family.
(Knox, 1983; Kumar et al. 1984)[1] In some diseases, the proportion of asymptomatic cases can be important.
Millions of women reported lack of symptoms during pregnancy until the point of childbirth or the beginning of labor; they didn't know they were pregnant.