Answer:
Because The less knowledge of medical supplies
Explanation:
When I answer this, I sorts think of "the mayflower" and other ship voyages. Back in those times I believe that they didn't have that good medical equipment and some disease that they never treated before was diagnosed! So when you had a disease on the ship, you basically a goner . (If it's correct or help you some, Could I get brainlist? If not have a great day -please rate fairly)