[PowderMonkey]

"I asked him how many of those serving at Guadalcanal caught malaria. He replied, “Everyone.” I thought he was exaggerating. He wasn’t."

You're right. He wasn't. When my family doctor was treating me for malaria, he told me of his father's experience with it in the Pacific theater during W.W. II. Everyone caught it. I've survived several different tropical fevers in my career. Malaria is a bear. It simply won't let go.

[PJ-Comix]

And I just did a quickie bit of research on Richard Tregaskis and, yes, he caught a touch of malaria as well. Avoiding malaria back then was like avoiding mosquito bites which was impossible.