BCG vaccine prevents severe tuberculosis disease
It is a live attenuated vaccine. BCG vaccine is given to prevent severe tuberculosis disease in countries where tuberculosis is very common.
This vaccine is derived from live attenuated strain of Mycobacterium bovis (Bacillus Calmete Guerin strain) which resembles Mycobacterium tuberculosis.
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How is the BCG vaccine available?
BCG is supplied as a pack of single vial of lyophilized powder in a vial and a single vial of diluent 1 ml.
Also a pack of 10 vials of lyophilized powder and 10 vials of diluent.
At what age to get the BCG vaccine?
BCG is a live vaccine for prevention of severe tuberculosis.
Give this vaccine for newborns as early as possible after birth.
Give this vaccine before the newborn is discharged from hospital.
It is most effective when given in infancy as early as after birth as it is used in countries where nearly one third of the population is infected with tuberculosis.
If someone has missed this vaccine it can be given till their fifth birthday.
As the age at which this vaccine is given increases its efficacy is not known.
How to give the BCG vaccine?
BCG vaccine is for intradermal injection.
Follow all the safety injection precautions for giving injections.
First take the diluent in a sterile syringe which does not contain preservatives and antiseptics or other drugs.
Then push the diluent in vial with lyophilized powder without forming foam.
Agitate gently and suck back the mixture in the syringe.
Do not apply antiseptics and spirit to vial.
Use the vaccine within 30 minutes of reconstitution or it should be discarded.
The antiseptic or spirit applied to skin before injection should vaporize completely before giving injection.
Inject the dose by intradermal route.
Give it on the left shoulder deltoid region.
Do not inject intramuscular or intravenous.
Disposable items used should be discarded as per local biomedical waste management protocols to protect your environment.
Dose of vaccine
For newborn age less than one month the dose is 0.05 ml and for above age 1 month it is 0.1 ml intradermal.
Correct technique of BCG vaccine administration
BCG vaccine is needed to be administered intradermally.
Intradermal administration of injection in newborn and infants need a certain amount of skills and practice.
Correct technique is important as it is needed for optimal effect of vaccines.
Skin is cleaned with normal saline solution at the injection site.
The skin is stretched with the thumb and index finger of one hand.
The dose vaccine is given using 26 no needle for intradermal injection.
The needed is inserted intradermally as parallel as possible to the skin.
The vaccine is injected slowly while removing the needle from the injection site slowly.
After giving intradermal injection there should be bleb formation locally. Usually for 0.1 ml injection 7 mm bleb is formed.
How to store BCG vaccine?
Store BCG vaccine as per recommendations of supplier or manufacturer.
Store this vaccine at temperature 2-8 degree Celsius.
It shouldn’t be frozen.
Maintain the temperature range using a strict cold chain.
Maintain the cold chain all all stages from manufacturer to the end user.
If the temperature recommendations were not followed, discard the vaccine.
While discarding local biomedical waste management protocols should be followed to protect environmental damage.
How Does the BCG Vaccine work?
BCG is a live vaccine.
When it is injected, the live bacteria in it infects you. It multiplies inside you like an actual disease causing bacteria.
This bacteria though live but attenuated cannot cause disease.
Your immunity recognizes this bacteria and develops an immune mechanism against it.
So when real infection occurs this developed immune system can fight back effectively.
Thus we can prevent severe tuberculosis disease from occurring.
This vaccine cannot prevent Tuberculosis infection but prevents severe tuberculosis disease.
Safety of vaccine with other vaccines:
BCG Vaccine should not be mixed with the same syringe with other vaccines or drugs.
BCG vaccine can be given at birth with oral polio vaccine and also Hepatitis B vaccine.
This vaccine is safe when given with other vaccines like DPT, HiB, rotavirus and Vit A supplements and measles and yellow fever vaccines.
What are the side effects of the BCG vaccine?
With this vaccine following are common side effects. These all side effects though occur generally are mild and can be managed at home and do not usually need admission. They usually occur in the first 5 days after vaccination.
- Pain, swelling, redness: Injection site pain, swelling and redness can occur within a few hours of giving this vaccine. It can be reduced with cold compression and medicine like paracetamol in adequate doses.
- Fever: Fever may occur within a few hours of giving this vaccine. It can be managed with or without medicines as needed symptomatically.
- Muscle pain: Limb pain muscle pain and fatigue are known side effects after vaccination. It usually subsides on its own. The intensity of side effects can be decreased with paracetamol.
- Anaphylaxis: Like all other vaccines and drugs this vaccine may cause anaphylaxis and severe allergic reactions. They are extremely rare to occur.
- Local reaction: is typical for this vaccine. Read following paragraph for details.
Local reaction to BCG vaccine or BCG scar
After correctly injecting this BCG vaccine intradermal local bleb will be seen immidiately after injection.
There is development of papule at the injection site in 2-3 weeks after injection. That papule appears red and increases further in site.
This papule may increase till 3-4 weeks in size to become 7-10 mm in diameter.
After a few weeks it subsides on its own or breaks.
If it breaks the pus like material is discharged from the site which is generally not painful.
It subsides in 6-12 weeks with scar formation at local sites.
BCG scars can remain there for many years.
In few patients there can be abscess formation and that too usually subsides by its own after drainage.
Very rarely patients may need surgical intervention for this abscess if there is infection of other bacteria in the abscess.

BCG Lymphadenitis
After BCG vaccination some patients may get enlarged lymph nodes in the axilla i.e. armpit.
Lymph nodes are local collection of white blood cells that fights infection.
This condition is rare and do not need treatment unless it is painful and tender.
Good counselling to parents with wait and watch is the desired approach even if patients gets swelling of other lymph nodes like in groin.
It usually subsides without any intervention in 6-12 months.
To whom BCG Vaccine should not be given?
In following cases this vaccine should not be given:
- Do not give this vaccine if the patient is known to be allergic to any of its components.
- Do not give this vaccine if the patient had got an allergic or anaphylactic reaction at the time of the previous dose.
- In pregnancy and breastfeeding mothers.
- Those who are immunosuppressed should not take this vaccine.
- Do not give this vaccine if the patient has symptoms of stage 3 or stage 4 of HIV AIds.
- Avoid this vaccine if the patient is on drugs causing immunosuppression.
- Deferral should be considered in acute illness (for example, in the presence of fever).
Warnings and caution
- This vaccine prevents tuberculosis but does not treat it.
- This vaccine may not protect all those who have received vaccination.
- Need of additional doses and booster is not yet known.
- Do not use this vaccine in pregnancy, lactating mothers and immunosuppressed individuals.
- Like any other vaccine, give this vaccine with readiness to manage anaphylaxis reaction.
- Local antiseptics used to sterilize skin should be adequately evaporated before giving injection intradermally or normal saline can be used to clean the local area instead of antiseptic like spirit.