Strongyloides stercoralis and Enterobius vermicularis are two different types of roundworms. They are not the same worm. The confusion lies with their layman names depending on which country you are in. Some people call Enterobius vermicularis "Pinworms" or "Threadworms". Some people call Strongyloides stercoralis "Threadworms". If everyone just used the scientific names for each there would be less confusion. You referenced only 2 worms, not 4. These are definitely two different species. I do not think treatment for each is exactly the same, but I could be wrong.