The Shaykh (Al-Mufid), may Allah
سبحانه وتعالى support him, further commented: "The same ruling applies to clothing stained with the blood of fleas and bedbugs. There is no harm if a person prays in such clothing, even if the amount of blood on it is large." This ruling is supported by the previously mentioned verse: 'He has not laid upon you in religion any hardship.' (Surah Al-Hajj
22:78) It is evident that flea blood is something that cannot easily be avoided. If a person were obligated to remove it completely, it would result in difficulty and hardship, especially since even after washing, the blood may reappear when the clothing is worn again. Thus, obligating constant washing would cause ongoing burden and prevent a person from fulfilling their prayers with ease. This ruling is also supported by other narrations indicating the removal of hardship in such cases.