What exactly did Jesus rebuke while healing the mother-in-law of Simon?

We read in Lk 4: 38-39 : > After leaving the synagogue he entered Simon’s house. Now Simon’s mother-in-law was suffering from a high fever, and they asked him about her. Then he stood over her and rebuked the fever, and it left her. Elsewhere, we see Jesus rebuking the evil spirit (Lk 9: 42). But it is doubtful if anyone who witnessed the healing believed that the fever of Simon's MiL had been caused by evil spirit. Even more doubtful is the existence of knowledge that it could have been caused by an animate thing say, virus . Even today, fever is more often than not, measured by the external symptom namely high temperature. Is it that Jesus rebuked the temperature which is an inanimate entity? My question therefore is: **According to Catholic scholars, what exactly did Jesus rebuke while healing the mother-in-law of Simon?**