Option 1: The recommended vaccination time is 28 to 60 days after the first vaccination. First, introduce the vaccination schedule. According to the domestic vaccination plan, the recommended interval is between 28 days and 60 days after the first vaccination for the second dose. If this time is exceeded and the vaccination effect is uncertain, it is recommended to get the first dose again and then the second dose according to the prescribed time. Why is it recommended to receive the second dose of vaccine within 28 to 60 days? This is because the human body can only produce the second dose of the vaccine about 14 days after vaccination.