So....
It's a more virilant form of the 1918 Spanish flu (
https://en.wikipedia.org/wiki/1918_flu_pandemic ) coupled with governments refusing to seem weak or actually inform their people about the impending problems, and with a bonus of 'even after they die victims will still be mobile and spread the disease'?
I think some of your collapse of society items are a bit pessimistic, a big one that comes to mind is that outside of the US and Japan there are very few 'super-critical' reactors (IE reactors that will melt down if no one is there to operate them). Canada, India, China, Iran, France, and England all use 'sub-critical' reactors; IE something must be done to maintain the reaction, and if that something stops you end up fusing the reactor chamber, but no out of control meltdown takes place.
As well, with most people dead (and therefore not around to use power) the hydro, solar, geothermal, and wind power contributions will happily operate without human intervention likely for years (my own solar install kept power available for my neighbors and myself after a lightning strike took out a supply line and I have literally done no maintenance on the system in 5 years). Though that could provide some eerie effects. Go into a rest stop on the highway to scavenge food, and when the sun comes up the lights all turn on and the muzak starts playing over the PA system.
Similarly unless someone is going out of there way to actually break things I would expect the cellphone system, telephone system, street lighting/traffic lighting, and many internet backbones to happily work away for years after all human intervention stops (though it may be spotty due to power constraints).
Similarly, depending on source, running water will continue for some time (how good that water is for drinking would be a different story), at least until unchecked growth on aquifers clogs the pumps.