The common reasons for the large lumps in the new crown vaccine are: malabsorption, local connective tissue hyperplasia, local infection, etc. 1. Malabsorption: If the speed of injection is too fast during the vaccination of new crown vaccine, the injection position is shallow and so on, resulting in local malabsorption, thus appearing lumps or hard lumps, usually accompanied by swelling and pain, fatigue, etc., the local should be given hot compresses and other treatments. 2. Local connective tissue hyperplasia: such as long-term vaccination or other drug injections, can also lead to stimulate the local hyperplasia, lumps, generally no obvious discomfort, without special treatment. 3. Local infection: such as after vaccination do not pay attention to the local hygiene of the inoculation place or the human body resistance is poor, there can be a bacterial infection at the inoculation place, thus appearing inoculation local lumps. But generally accompanied by: redness, swelling, heat, pain, fever, subcutaneous pus and other symptoms. If the lump is large after vaccination, you should contact the vaccination hospital in time to avoid aggravation of the condition.