Different vaccines are suitable for different groups of people. Some common groups of people who are not suitable for vaccination include those who are allergic to vaccines, those who have acute onset of chronic diseases, those who have defective or impaired immune system, those who are mentally ill, and those who have bleeding tendency. 1. Vaccine allergy: most of the main components of vaccines are proteins, so people who are allergic to them should not be vaccinated. People who have had serious adverse reactions to vaccination, such as acute allergic reactions, urticaria, angioneurotic edema, respiratory distress, shock, etc., are not recommended to receive vaccination. 2. Acute exacerbation of chronic diseases: such as active tuberculosis, severe hepatitis, and acute exacerbation of chronic kidney disease, etc., vaccination is not recommended. 3. Impaired immune system: People with autoimmune diseases, such as acquired immunodeficiency disease, rheumatoid arthritis, systemic lupus erythematosus, leukemia, etc., are not recommended to receive the vaccine. 4. Mental illness: people with mental illness, epilepsy, and other neurological disorders are not recommended for vaccination. 5. Bleeding tendency: People with thrombocytopenic purpura, anaphylactic purpura or other blood system diseases are not recommended for vaccination. 6. Others: Pregnant women and lactating women during pregnancy should be cautious of vaccination. Some vaccines have age limitations, so it is recommended to ask relevant professionals before choosing whether to vaccinate. In other cases, it is recommended to consult a doctor before making a judgment.