Nosophobia
Nosophobia is the irrational fear of contracting a disease, a type of specific phobia. Primary fears of this kind are fear of contracting COVID-19, HIV, pulmonary tuberculosis, venereal diseases, cancer, heart diseases, and catching the cold or flu.
Some authors have suggested that the medical students' disease should accurately be referred to as "nosophobia" rather than "hypochondriasis", because the quoted studies show a very low percentage of hypochondriacal character of the condition.
The word nosophobia comes from the Greek νόσος nosos for "disease".