4.2.1 Intradermal immunization with BCG vaccine
Intradermal (ID) means within or between the layers of the skin (dermis). BCG vaccine is the only EPI vaccine which is given intradermally. BCG vaccine should be reconstituted with the appropriate diluent before administration, as described in Section 4.2 above.
Swab the outer surface of the child’s outer upper right arm with antiseptic solution and allow it to dry. Select a sterile 0.1 ml syringe with a 26 gauge needle (Figure 4.12) and draw 0.05 ml of the reconstituted BCG vaccine into the syringe. Hold the syringe with the needle pointing upwards and tap the syringe so any air bubbles float to the top of the barrel. Gently push the plunger just enough to expel the air through the needle — you should see a tiny drop of vaccine emerging from the tip of the needle. This ensures that you do not inject air into the child’s skin. Make sure the vaccine dose is exactly 0.05 ml by checking the scale on the barrel of the syringe.
Ideally you should use auto-disable (AD) syringes with needles attached.
Why should you use a 0.1 ml syringe to inject BCG vaccine and a 1 ml syringe for all other injected EPI vaccines?
The dose of BCG vaccine is very small – only 0.05 ml. In order to measure and inject such a small dose accurately you must use a 0.1 ml syringe. All other injected vaccines are given in doses of 0.5 ml, so you should use a 1 ml syringe.
Inject the recommended dose of 0.05 ml of reconstituted BCG vaccine into the most superficial layers of the skin (intradermally) in the upper right arm. You should insert the tip of the needle just under the skin by inserting the bevel and a little bit more of the needle into the skin, while keeping the bevel facing upwards (Figures 4.13). The syringe should be lying along the child’s arm (Figure 4.14.)
The reason for injecting the vaccine in the same place (upper right arm) for each child is to make it easy to find the BCG scar subsequently. This enables you to check that the immunization has been effective. If the child does not develop a sore at the injection site, which heals to form a small scar (see Figure 2.3 in Study Session 2), the BCG vaccination should be repeated.