Self-funded vaccines, also known as Class II vaccines, are self-funded and voluntary vaccines that are recommended only when available and not contraindicated, and are not mandatory. Since infants and children are weaker and less able to resist viral attacks, early vaccination is recommended. There are no five vaccines that are clinically mandatory, but the following are common self-funded vaccines: 1. Rotavirus vaccine: The main purpose is to prevent rotavirus enteritis, and it is recommended for children aged 2 months to 3 years. Common adverse reactions include occasional symptoms such as low fever, lack of appetite, and decreased mental vigor about 5 days after the first dose of vaccination, only mild fever in the second dose, and rare adverse reactions in the third dose. Since older children can have more obvious side effects after the first dose, it is recommended that the first dose be given before 6 months of age. 2. Live attenuated varicella vaccine: It is suitable for the prevention of varicella in young children over 12 months of age as well as in healthy individuals. Usually 1 dose for 12 months to 12 years old and 2 doses for 13 years old and above, with an interval of about 6-10 weeks, depending on the requirements of the vaccination department; 3. Pneumonia vaccine: prevention of pneumonia caused by pneumococci. 7-valent is pneumonia conjugate vaccine, mainly for children under 2 years old. 23-valent is pneumococcal polysaccharide vaccine, for children over 2 years old and healthy people, adverse reactions The main adverse reactions are redness, swelling and fever at the vaccination site that can heal spontaneously, with occasional symptoms such as low fever, weakness, arthralgia and rash. 4. Influenza vaccine: It is mainly used to prevent influenza, or influenza for short, and is suitable for children under 5 years old, and adults can also be vaccinated. The main adverse reactions include pain at the vaccination site, generalized fever, etc. and the need to stay for about 30 minutes after vaccination; 5. Hand, foot and mouth disease vaccine: Hand, foot and mouth disease is a common infectious disease in children, with enterovirus infection common, the recommended starting age for vaccination is 6-10 months of age, and children between 6 months and 5 years of age should be vaccinated as early as possible. In particular, prevention of severe hand, foot and mouth disease. In addition, self-funded vaccines such as hepatitis A vaccine and Haemophilus influenzae type B vaccine (HIB vaccine) are also useful for disease prevention, and patients can receive them voluntarily under the guidance of their doctors. It is important to clarify that vaccination does not mean complete immunity, and patients need to take precautions and raise awareness of hygiene during periods of high disease prevalence and in their daily lives.