How does someone get lemierre's disease? i've heard if you had strep and never got treated for it it can happen this way?

Lemierre's syndrome: Or jugular vein suppurative thrombophlebitis can be a sequel of pharyngitis, usually in association with tonsil or peritonsillar involvement & sometimes dental infection as well as mono. It could be a complication of untreated strep throat, but the condition is most commonly caused by non-strep bacteria, usually by bacteria found in the normal oral flora.