Last I read about the Texas case it'd been estimated he'd had contact with 80 people before being diagnosed properly, though only four of his immediate family members were forced into isolation for 21 days (enforced by cops stationed outside their door).
His getting sent home after his first trip to the ER was our version of the Liberian clinic raid--intense stupidity at precisely the wrong time. Even if you trust the articles saying he wouldn't be contagious until he showed symptoms--which, as I've pointed out before, seem to be contrary to articles and factsheets posted prior to this case--you can be sure he had contact with others after
showing symptoms thanks to the ER staff.
I also recall mention that someone who recovers can still be contagious a while (a couple weeks I think?) after symptoms subside, so I'm interested in the areas where the health staff brought in from Africa for treatment in the US to see if any cases turn up there as well. It also bothers me that the communicability stats are changing ever since ebola landed in the US. Probably done to keep people from panicking, but could backfire when people take it as true. Also not too thrilled with officials following the historical cases as gospel; if the disease was never observed to incubate more than 21 days, isolate for a month would be my answer, not cut it off on right at 21 days on the button. Err on the side of caution.