So I’m really stealing this term from someone else but I thought it was funny.
There are a lot of medical brigades here. Basically, a group of doctors from the US comes down here for a week. They travel to some rural village where there are no medical facilities and treat patients and distribute medicine. In some cases they come to the same village every year – so it is basically like the annual trip to the doctor for the people of the town.
In some cases there is an urgent medical need – and the people have been waiting for the medical brigade to show up to get treatment.
In other cases, there is no real medical need, but the people wait in line anyways for the doctors in hopes of getting some medicine.
These people are called ‘Trick or Treaters’.

