The Arabs say: "Nufisat" (3) the woman, when she menstruates, and she is "nufisat" from nifas (postpartum bleeding).
And everything that does not have flowing blood, such as what Al-Khiraqi mentioned from land animals, or sea animals—like leeches, worms, crabs, and the like—does not become impure by death, nor does the water become impure if it dies in it, according to the statement of the general body of jurists. Ibn al-Mundhir said: I know of no disagreement regarding that, except for one of the two opinions of Al-Shafi'i; he held two opinions regarding it. One of them is that a small amount of water becomes impure. Some of his companions said: This is the analogy (qiyas). The second is that it does not become impure. This is more appropriate for people. As for the animal itself, it is in his view impure, in a single opinion, because it is an animal whose meat is not consumed, not due to its sanctity, so it becomes impure upon death, like the mule and the donkey.
Our evidence is the statement of the Prophet (peace and blessings of Allah be upon him): "If a fly falls into the vessel of one of you, let him submerge it (fal-yamqulhu), for in one of its wings is a disease, and in the other is a cure." Reported by Al-Bukhari and Abu Dawud (9). In another wording: "If a fly falls into the drink of one of you, let him submerge it (falyaghmishu) completely, then cast it away, for in one of its wings..."
(3) From the verb form 'ta'iba'. It was reported from Al-Asma'i that it is "nufisat" in the passive voice as well, though it is not well-known in books. Al-Misbah al-Munir. (4) In M: "the land animal". (5) In M: "from it". (6) Omitted from A. (7) From: Al-Asl. (8) Omitted from A. (9) With the wording "fal-yamqulhu" or "famqulu hu", it was reported by Abu Dawud, in: Chapter on the fly falling into food, from the Book of Food. Sunan Abi Dawud 2/328; Ibn Majah, in: Chapter on a fly falling into a vessel, from the Book of Medicine. Sunan Ibn Majah 2/1159; Al-Nasa'i, in: Chapter on the fly falling into a vessel, from the Book of Al-Far' and Al-'Atirah. Al-Mujtaba min al-Sunan 7/158; and Imam Ahmad, in Al-Musnad 3/24, 67. And with the wording: "falyaghmishu" it was reported by Al-Bukhari, in: Chapter on if a fly falls into the drink of one of you, etc., from the Book of the Beginning of Creation, and in: Chapter on if a fly falls into a vessel, from the Book of Medicine. Sahih al-Bukhari 4/158, 7/181; Ibn Majah, in: Chapter on a fly falling into a vessel, from the Book of Medicine. Sunan Ibn Majah 2/1159; Al-Darimi, in: Chapter on the fly falling into food, from the Book of Food. Sunan al-Darimi 2/99; and Imam Ahmad, in Al-Musnad 2/229, 230, 246, 263, 340, 355, 388, 398, 443.