I should also mention, if it snows, the road will be closed with the only vehicles moving may be vendors or Park personnel, I was able to catch a ride with Park help back to close to my car. The next year, I hiked thru 4" of snow my second day in my shorts, eating dinner that night in my bag. The very next day, I was swimming and had my gear on rocks drying a little, turned out to be a great trip. When I got back to my car, there was a flyer on the windshield stating the road to the east over Tioga Pass was closed due to snow. :), Well by the time I got back, all the snow had melted and I had now issues. If it snowed and you could hang in there a day or two, things might work out, just trying to rely on others may be hard. The year I abandoned my trip and went home, I saw some people around Sunrise Lakes and close to Teneya, the next year doing the same High Sierra Camp loop, I saw no one on my trip. I've been snowed out the last two years for trips down south, so had to either then stay home or do a short car camp trip close to home instead, thus my decision to go on vacation earlier this year and do a car camp trip instead of my normal bping.
The Hanta virus is only at the campground that has those canvas shelters, if you stay in a bpers cg, you should be fine. We only have the Bubonic plaque up north here at Plumas Eureka State Park last year.