I don't think that matters. St. Athanasius is universally respected.On the Incarnation is not infallible.
It's awfully reliable and accepted though. To distrust St. Athanasius the Apostolic, would require much stronger arguments with patristic support than "it doesn't seem right to me".
Before the fall, Adam and eve ate, felt emotion, were fully human. But they were not subject to corruption, disease, fear of animals. They had dominion over creation, so an animal could not attack them, their master. A virus for a bacterium could not attack in the same way.
Through sin, death and corruption entered the world. Man became vulnerable to everything from a lion to a virus.
The righteous though, often manifest a restoration of this dominion. Daniel was saved by God from the lions in the den. Many of the saints, until today, could pat a lion with no fear or harm.
Christ took upon Himself our very nature, with death in it, and defeated that death on the cross. But His Body, though separated from His Spirit, remained united to the Godhead, and did not suffer corruption. I cannot imagine Christ, greater than any of the saints, being afraid of a lion. He never sinned, He is perfectly righteous, He is the creator of all. Surely He would have dominion over the lion. Just as surely He would have dominion over the virus or bacterium. I don't think that corruption won a few rounds with Him, weakening Him through disease, but was ultimately defeated by Him upon the Cross. I think that He was victorious, our saviour, from the moment of His conception until His Resurrection, defeating death, until His Ascension and Second Coming.
Sweating, laughing, eating. These are normal human functions. Illness is not. It is a result of our fall. The sickness He bore is our sin, the death in us, not a virus. Christ bore our sickness, death, but He defeated it, He did not succumb to it. I see nothing that necessitate finding fault in St. Athanasius, were any of us even remotely qualified to do so without reference to a single conflicting patristic opinion.