I need to end my essay. I already mentioned what causes it, what it is, and how it is cured but I still need...

Your question calls for an "end" to your essay, but then
suggests that you need "more."  Be careful.  A conclusion is different from another body
paragraph.  If you need to introduce a completely new sub-topic, you are simply adding
additional information and will also need a separate conclusion.  From the sound of the
points you have covered, your essay seems to be thorough.  If it is for lack of enough
words/pages to meet a requirement, at this point, you have a couple of
options.

The first option is to go back and look for places
to include additional examples and elaboration to the body paragraphs you have already
written.  Another idea is to add another subtopic that is different from those you
have.  You talk about "cures" but what about complications?  What is life like for those
who live with this disease?  Is there anyone famous who has suffered from this disease
that you could talk about as a special interest
section?

When you are ready to fully
end your essay, you will sum up the  main points you have made (essentially
restating your thesis in a slightly different way) and leave the audience with something
to think about.  See the link below for some general advice about
conclusions.