[raybbr]

Just follow the paths of illegal aliens. Do the same for whooping cough. It should be pretty easy to find out where they came from.

[muawiyah]

Not to bust your bubble but around here most TB has two sources ~ junkies and people who've simply been visiting a foreign location where TB is present.

Your community may be different with no junkies and nobody making visits to such places. Others might be in between.

The vector is simple ~ a human being with an active case of TB with whom you come in contact for several hours.