What spider bites require emergency care?

Other parts of the world.

1.The Redback Spider

2.The Tree-Dwelling Funnel-Web Spider

3.Brazilian Wandering Spider

USA.

4.Brown Recluse Spider

5.Black Widow Spider

6.Brown Widow Spider

Both

7.tarantula worst of them all never try to have one as a pet all of them.It will be deadly.