BCG is a vaccination against tuberculosis, a dangerous infectious disease, even today leading to death without correct treatment. Today, vaccination is the only effective method of preventing tuberculosis. The vaccine is administered intradermally into the baby's left shoulder on days 3-7 of life while still in the maternity hospital. If for some reason the vaccine was not given, the procedure is carried out later, in the vaccination office at the child’s place of residence after consulting a doctor. After injection of the drug, a papule forms at the injection site, which then scars. The mark from the vaccination is a scar, otherwise called a post-vaccination sign. Scarring is considered a normal reaction of the body to BCG. In some cases, no trace of the BCG vaccination remains. Or there was a post-vaccination sign, but it resolved very quickly and disappeared.
In 10 percent of cases, adults have no trace after BCG vaccination. You need to know how to distinguish a normal variant from an ineffective vaccination.
Why will there be a vaccination scar on my shoulder?
BCG vaccination is carried out only after a thorough examination and examination of the newborn child. If there are no contraindications to immunization, the baby is healthy and his weight is not less than 2500 g, the vaccination is given in the maternity hospital on the third day after birth. Immediately at the injection site, a papule swells - a small pad no more than 1 cm in diameter. After half an hour, the papule resolves on its own. This is a natural reaction to the injected tuberculin. She speaks of a correctly administered vaccination, and also that the formation of immunity has begun.
What indicates the emergence of immunity to tuberculosis?
Over time, at the injection site, the injection mark turns into an abscess. This happens a month and a half after the BCG was done. Some parents are very embarrassed and frightened when the papule takes on a bluish, purple, or burgundy hue. Such changes are completely natural and confirm that the process of developing immunity is proceeding normally.
Immunity to tuberculosis will be fully formed within 4-4.5 months from the date of vaccination. During this period, the papule may fill with purulent contents, break through, and become covered with a crust. That's how it should be. In order for the pustule to heal correctly, without complications, caring for the pustule during the process of healing and the formation of immunity is also important. The following rules must be followed:
- do not open the pustule or squeeze out the pus;
- do not smear the pustule with alcohol solutions, brilliant green, iodine;
- do not sprinkle with talc, zinc and other antiseptic powders;
- do not cover the vaccination site with a band-aid;
- It is forbidden to peel off the crusts.
Gradually the pustule heals and leaves the same BCG scar. The BCG trace in newborns and its condition is an indicator of how the body develops anti-tuberculosis immunity. A child's BCG scar is used to evaluate how well and effectively the vaccination against tuberculosis was carried out. Therefore, if there are no traces left after vaccination, this is always a reason to consult a doctor and find out the reason why there is no trace of BCG.
Normal post-vaccination sign
So, a positive reaction to an anti-tuberculosis vaccination can manifest itself as the formation of a purulent pustule, a change in the color of the skin, or a slight increase in body temperature during the formation of the abscess. A doctor's help is not required for such symptoms. You should contact a specialist only when symptoms appear that indicate the presence of infection and complications - if the skin all over the shoulder turns red and swells, the baby is very restless, a rash appears, and a high body temperature. In other cases, the child is shown to the pediatrician when the abscess is completely healed.
The level of acquired immunity to tuberculosis and the duration of its action are assessed as follows:
- Low – the size of the scar is less than 4 mm. This immunity will last for about 3 years.
- Medium - the size of the scar varies from 4 to 8 mm, it is believed that immunity will last up to 6-7 years. At this age, BCG revaccination is carried out.
- High - if the size of the scar exceeds 8 mm, it is believed that such immunity will last for 7 years or more. In this case, revaccination is still carried out first at 7 years of age, and then the last time at 14 years of age.
Sometimes the baby does not have a scar at all after vaccination, or it dissolves very quickly.
Expert commentary
How a scar develops at the injection site
BCG is a “live” vaccine: the preparation contains a suspension of weakened tuberculosis pathogens. Once bacteria enter the body, they trigger a powerful immune response. White blood cells (protective cells) actively destroy and absorb bacteria, as a result of which a slight inflammation develops at the site of vaccine administration. The mechanism of the immune response is similar to the body’s response when microorganisms enter an abrasion or cut. Therefore, after BCG vaccination, the following changes are observed within 6 months:
- after 4-6 weeks a spot appears
- the spot turns into an infiltrate (dense area of skin) with a diameter of up to 10 mm
- then a bubble with transparent contents up to 10 mm in diameter appears at the site of infiltration
- the contents of the vial become cloudy
- a crust forms in place of the bubble
- the crust disappears and a scar up to 10 mm appears in its place
Do I need to take care of the injection site?
The vaccine injection site does not require special care. There is no need to pierce the vial to release the liquid, try to remove the crust yourself, or wipe the injection site with alcohol or other solutions.
What symptoms should you contact your pediatrician for?
Seek advice from a specialist if you experience the following:
- A lump at the vaccine injection site greater than 1 cm in diameter
- The child has enlarged cervical, axillary, supraclavicular and ulnar lymph nodes
- The temperature has risen, the child refuses food and water, and vomiting has appeared
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Why is there sometimes no trace after a BCG vaccination?
The absence of a trace after BCG can occur in two cases:
- The child has strong congenital resistance to tuberculosis - this phenomenon is observed in approximately 2% of the population. In this case, natural immunity kills the rod even before it has time to penetrate the cells and give an inflammatory reaction.
- The vaccination was not carried out correctly and did not give the expected results: the child did not develop immunity against tuberculosis. The reason is most often a low-quality, expired or improperly stored vaccine. Or in the inexperience of the medical worker who performed the procedure: the vaccine must get strictly intradermally, and not under the skin.
The latter situation is especially dangerous. After all, this means that the baby is at increased risk. And in case of tuberculosis, he will endure the disease with difficulty, with unpredictable consequences and complications. In this case, repeated administration of the vaccine is necessary.
What does it mean if there was no trace after BCG at all?
If there is no trace of BCG, and there was not, then this most likely indicates that the vaccination was carried out incorrectly. In this case, doctors recommend revaccination earlier than the dates specified in the national vaccination calendar. That is, not at 7 years old, but two years after the first unsuccessful immunization. During this period of time, the child is constantly given a Mantoux or Diaskintest test in order to identify the infection as early as possible in the event of tuberculosis infection.
If the Mantoux test is always negative, after 2 years the vaccination is repeated no later than 2 weeks after the last tuberculin test. If the BCG revaccination did not give any reaction, this means that your child has a rare case of innate immunity against tuberculosis. If the reaction is positive or questionable, BCG vaccination is strictly prohibited.
Why was there a trace, but disappeared?
In children, the scar resolves and disappears, usually due to the expiration of immunity. This happens if the parents did not show the baby to the doctor in a timely manner after vaccination, if the vaccination was carried out incorrectly or if a low-quality drug was used. The scar resolves as the child grows older and the instilled immunity decreases. If the scar resolves on its own ahead of schedule, this means that revaccination is required. But, again, Mantoux’s reaction should be negative.
Characteristics of the positive qualities of the vaccine
Possessing high protective properties, the domestic vaccine produces a minimal number of adverse reactions. Among its important qualities it should be noted:
- specific harmlessness. During vaccine production, strict control is ensured over the level of residual virulence of the strain necessary for the formation of immunity, in order to prevent the virulence index from increasing to a value dangerous for the human body;
- purity (this indicator indicates the absence of impurities of foreign microflora in the composition of the drug);
- stability of the total bacterial content, allowing residual virulence to be maintained at the required level, without increasing or decreasing it;
- specific activity - this parameter indicates the number of viable bacteria in the preparation. Any fluctuations in one direction or another can make the vaccine unsuitable for use: a decrease in the number of such bacteria will reduce the vaccine’s ability to develop immunity against tuberculosis in the human body, and an increase in them will make it dangerous;
- high dispersion index - not lower than 1.5. This characteristic shows the degree of presence of suspended particles in the composition of the grafting suspension - the smaller they are, the more homogeneous the suspension and the higher the dispersion;
- thermal stability - the ability to retain the maximum number of viable microorganisms when storing the vaccine in a thermostat;
- solubility - when adding a solvent, the contents of the ampoule should dissolve in it within 1 minute;
- the presence of a vacuum in sealed ampoules with grafting material.
We recommend reading! Follow the link: Anti-tuberculosis BCG vaccination
The BCG vaccination is absolutely harmless. In rare cases, side effects are possible after vaccination in the form of redness and swelling of the arm, and fever. But the risk of their occurrence and the severity of the consequences are incomparable with the consequences of infection with a lethal form of tuberculosis.
Complications after BCG
If the procedure and technique for administering the BCG vaccine are violated, complications may occur, and, as a rule, immunity to tuberculosis remains undeveloped.
The following adverse effects are considered:
- If, contrary to the rules, the drug was not administered intradermally, but subcutaneously, a cold abscess (an accumulation of pus without other symptoms of the inflammatory process) and the formation of an ulcer may form at the site of drug administration.
- In severe cases, BCG vaccination can lead to bone tuberculosis and inflammation of the lymph nodes.
- If contraindications were not taken into account when performing BCG, a BCG infection may develop, which causes inflammatory processes in the body.
- A fairly common complication of BCG is the formation of a keloid scar at the injection site. This is observed over time, usually a year after the child is given BCG, in the form of a thickening, accompanied by a change in skin color (a dark pink, bluish tint is possible), the scar is formed not on the surface of the skin, but under it, has an irregular shape, and is deformed.
In this case, a keloid scar can be growing or non-growing.
This phenomenon occurs due to improper administration of the vaccine and against the background of a genetic feature when the connective tissue tends to grow.
Within the growing keloid scar, a multiple network of capillaries can be visualized. The surface of the skin at the site of scar formation is smooth and shiny. Pressing on the scar becomes painful and can cause itching from time to time.
You need to know that a growing scar will not go away on its own; therapy will be required, with the help of which it is sometimes possible to stop the growth of connective tissue. But if this condition began after revaccination (and most often keloid scars appear just after repeated vaccination), drug therapy most often turns out to be powerless, and the growth of the scar continues.
In addition to the keloid scar, sometimes a hypertrophic node forms at the site of BCG, which does not pose a danger to humans - it does not cause any discomfort and is prone to spontaneous resorption. The surface of the skin in its place is slightly different in color, not smooth, as with a keloid, but slightly rough.
