FeverBible History (which does not mean that modern day humans should not make proper use of antibiotics if prescribed by a doctor).
"He touched her hand, and the fever left her"
The second public miracle of Jesus Christ was the healing of a child's fever.
"4:46 So Jesus came again into Cana of Galilee, where he made the water wine. And there was a certain nobleman, whose son was sick at Capernaum. 4:47 When he heard that Jesus was come out of Judaea into Galilee, he went unto him, and besought him that he would come down, and heal his son: for he was at the point of death [see What Happens When You Die?].
Although fever is usually the result of the body's immune system fighting an infection, ironically, those who get some kinds of infections are often those with weak immune systems - a potent immune system will eliminate a threat before an all-out war, a fever, against an out of control infection can happen. The specific recorded incidents of healing of fever were either that of the young (those whose immune system is not yet well developed) i.e. the nobleman's child, as recorded above, or older people (those whose immune system may not be functioning as well as it used to) i.e. the father of Malta's governor, as recorded below, and this example of Peter's wife's mother. The healing of fever was often then accompanied by healing of other sorts of ailments, physical, psychological - and spiritual (true Christians have their own sort of immune system against demonic infection i.e. the Holy Spirit).
"8:14 And when Jesus was come into Peter's house [see also Peter's Ministry and Houses Of The Holy], he saw his wife's mother laid, and sick of a fever. 8:15 And he touched her hand, and the fever left her: and she arose, and ministered unto them.
"28:7 In the same quarters were possessions of the chief man of the island, whose name was Publius; who received us, and lodged us three days courteously. 28:8 And it came to pass, that the father of Publius lay sick of a fever and of a bloody flux: to whom Paul entered in, and prayed, and laid his hands on him, and healed him. 28:9 So when this was done, others also, which had diseases in the island, came, and were healed" (Acts 28:7-9 KJV)
Fact Finder: What part does faith have in healing?