No, there are really no weird diseases. There may be diseases that people have never heard of or experienced and this may make them weird. However, this disease is common in that people are more aware of this disability and schools have now prepared themselves to make the children who have Down Syndrome and other common disorders to be successful in school and in life.
There are many jobs that can be done with people with disorders. They work in all walks of life. Therefore, it is not weird because it has become so common. Many people would recognize the disorder if someone talked to them about it. They would not stare because they are used to seeing people with Down Syndrome and know that it is rude to stare.