I was running my players through Wave Echo Cave in LMoP today and they happened upon a very large group of Stirge. They have low AC and even lower HP, so I didn't think this would pose much of a problem. When the Stirge surprised half of my players, however, and began hitting them with Blood Drain , I became concerned.
Blood Drain: ..the stirge attaches to the target. While attached, the stirge doesn't attack. Instead, at the start of each of the stirge's turns, the target loses hit points due to blood loss. ...A creature, including the target, can use its action to detach the stirge.
I am wondering, if the description of this attack makes a point of saying a creature can use an action to remove the Stirge, as opposed to just using your action to attack a Stirge attached to your friend like any player would normally attempt, is this saying you can't attack the Stirge when it is attached to a creature and must, instead, use your action to remove it?
Keep in mind that all Player Characters are Medium, and at the smallest of them Small, sized creatures. A stirge is a Tiny creature, that has attached itself to a (in most cases) much larger creature to draw blood. I can't imagine the Paladin being able to swing on it with his Greatsword to desired effect.