Book club edition; lacks ISBN

The cabin had always been a special retreat for Isherwood Williams, a haven from the demand of society. But one day while hiking, Ish was bitten by a rattlesnake, and the solitude he had so desired took on dire new significance.
He was sick for days -- although, somehow, he never doubted that he'd live through the ordeal. Often delirious, he did awake at one point to find two strangers peering in at him from the cabin door. Yet oddly, instead of offering help, the two ran off as if terrified.
Not long after that, the coughing began. Ish suffered chills followed by fever, and a measles-like rash that had nothing to do with snake bite broke out on his skin. He was one of the few people in the world to live through that peculiar malady, but he didn't know it then.
Ish headed home when he finally felt himself again -- and noticed the strangeness almost immediately. No cars passed him on the road; the gas station not far from his cabin had an air of abandonment; and he was shocked to see the body of a man lying by the roadside near a small town.
Without radio or phone, Ish had no idea of humanity's abrupt demise. He had escaped death, yet could not escape the awesomeness of the catastrophe -- and, with an eerie detachment, he found himself curious as to how long it would be before all traces of man's civilization faded from the Earth.
At the same time, he couldn't help wondering whether others had survived, and whether even a handful of human beings would ever be able to rebuild their world ...