This vaccine only requires one injection in a lifetime, and it is not recommended for children over 4 years old!

Author: Wang Lin, Chief Physician, Children's Hospital, Capital Institute of Pediatrics

Vice Chairman of the Children's Health Branch of the Chinese Association of Preventive Medicine

Reviewer: Dong Jian, Chief Physician, Zhongshan Hospital, Fudan University

Vice Chairman of the Science Popularization Branch of the Chinese Medical Association

Before liberation, China was a country with a high tuberculosis incidence rate. By vaccinating with tuberculosis vaccine, namely BCG, we can prevent tuberculosis and reduce the incidence of miliary tuberculosis and tuberculous meningitis.

BCG is a live vaccine made from a suspension of attenuated bovine tuberculosis bacteria. It is a powerful weapon for preventing tuberculosis, so it is recommended to be vaccinated as soon as possible after the baby is born if there are no contraindications.

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BCG is a national immunization program vaccine and is provided free of charge by the government. If there are no contraindications to vaccination, BCG, like the hepatitis B vaccine, should be administered within 24 hours of birth. The two vaccines are administered almost at the same time, with BCG administered in the left upper arm and the hepatitis B vaccine in the right upper arm.

Unlike the hepatitis B vaccine, BCG only needs to be administered once, just one shot, while the hepatitis B vaccine requires three shots.

1. If the baby was not vaccinated with BCG on the day of birth, when can he get the booster shot?

When the baby is just born, BCG vaccination may be delayed due to various contraindications to the vaccination, such as immunosuppression or deficiency, progressive neurological diseases, premature babies, birth weight less than 2500 grams, asphyxia and hypoxia at birth, severe jaundice, etc.

At this time, parents must pay attention to this matter. After the baby's body recovers, go to the community health service center for booster vaccination as soon as possible. It is recommended to vaccinate within 3 months of age, because if the baby is vaccinated after 3 months of age, a skin test will be required, that is, a PPD (tuberculin test) skin test must be performed first. Only after the skin test is negative can the BCG vaccine be administered. At this time, the baby will need to get one more shot.

If the baby's physical condition makes it impossible to be vaccinated before three months of age, it is still recommended that parents give the baby the BCG vaccination as soon as possible if the baby is over three months old.

The maximum age for BCG vaccination is now 4 years old. It is not recommended to give booster shots after 4 years old. It should be completed before 4 years old. Of course, for comprehensive considerations such as BCG safety and effectiveness, vaccination should be completed within 1 year old as much as possible.

Why is vaccination not recommended after the age of 4? Because babies can move around on their own and have a relatively large range of activities, it is easy for them to have asymptomatic infections and produce antibodies in the body, so they are not suitable for BCG vaccination.

2. What adverse reactions may occur after the baby is vaccinated with BCG?

After the baby is vaccinated with BCG on the day of birth, there will generally be no adverse reactions at the time, but the adverse reactions will appear about one month later.

After a month, parents will find some local redness and swelling, which will gradually turn into purulent ulcers and scabs. It takes about two to three months from the appearance of redness and swelling to purulent ulcers and scabs. That is, when the baby is about three months old, the local ulcers will scab over, then heal, and slowly form scars.

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During this process, parents do not need to do any special treatment, just pay attention to cleaning and prevent secondary infection. When there are pustules or ulcers, do not apply medicine to the baby or apply local bandages. Just expose it and do not do any special treatment. Excessive intervention, such as using some unclean cotton swabs to wipe the suppurated or ulcerated areas, may cause local infection.

If the local abscess or ulcer is larger than one centimeter or does not heal for a long time, you should seek medical attention immediately.

Some parents also find that their baby's axillary lymph nodes are swollen, and some even form pustules. At this time, they should seek medical attention in time and receive local treatment.

Some babies may experience transient fever, but most of them are relatively mild and usually do not last more than two days. Parents do not need to worry too much and can provide timely symptomatic treatment.

In the past, babies would be rechecked three months after receiving the BCG vaccine. However, with the significant improvements in BCG vaccination by the National Disease Control and Prevention Agency, rechecks or booster shots are no longer necessary. Even if no BCG scar is formed after vaccination, booster shots will not be given.