noun
epidemiologist
A specialist who studies the patterns, causes, and effects of health and disease conditions in defined populations.
彼は感染症の研究をしている疫学者です。
He is an epidemiologist who studies infectious diseases.
疫学者たちは新しいウイルスの広がり方を調査している。
Epidemiologists are investigating how the new virus spreads.
A general medical doctor; an epidemiologist may or may not be a practicing physician.
Compound of 疫 (えき, 'epidemic') + 学 (がく, 'study') + 者 (しゃ, 'person'). The term is a straightforward Sino-Japanese formation.