When the adult worm settles in the lymph glands, the scarring that follows creates chronic lymphatic obstruction, the same manifestation as congenital lymphedema, but an acquired version of it. Here I have seen a few people who have gotten it in their childhood in Guyana, for instance, and have had repeated episodes of acute filariasis. And they come here about 10 or 20 years later with the chronic manifestations of it. The disease is treatable - there are drugs which attack the smaller stages of the worm in the bloodstream. But once it has come to the chronic scarring stage, then the management is identical to any other kind of lymphedema.
Filariasis is a common mosquito-born disease of any part of the tropics.
The ones who would get missed at the acute stage would go on to develop chronic problems and those are the ones who would be seen later - maybe 20 years. Treatment depends on the availability of health care. As a result a lot of people tend to come to doctors at the chronic stage. Once the scarring takes place it is a major scarring and it is a very similar experience to the Canadian experience of people who have had lymph nodes excised as part of cancer management, whereas with congenital lymphedema very often there are some lymphatics which are still functioning and the limbs are often not massive. A lot of people with congenital lymphedema cope with it without it developing into the elephantiasis stage.