I also get the thumping as well as twitches and vibrating.
I'm not sure many of us know how we became infected.
I know that I personally encountered any third world country residents while perusing this site....most appear to be educated people living in America, Canada, Britain or Australia. Again, this is my own personal experience.
I am also super clean but perhaps the person that served me my food at a restaurant was not, you know?
Just a guess.