Vaccination is a procedure by which we introduce dead or modified microbial germs or, more often, parts of them into the body, by which we stimulate the immune system to create effective protection against infection. Most vaccines are given by intramuscular injection.
Parts of the microbial germs or with additional substances called adjuvants, create an inflammatory reaction at the injection site, so within 48 hours, usually after the first 6-8 hours, redness, tightness, tenderness, soreness and swelling appear locally.
Sometimes the inflammatory reaction is wider, with symptoms of transitory fever, a feeling of weakness or muscle pain. Initial local inflammation is necessary to provoke a real immune reaction. This type of side effect is called reactogenicity.
Some vaccines have side effects that we classify as side effects. For some we know that they are related precisely to the properties of vaccines, and for some we only know that they occur over time in relation to certain vaccines, although the mechanism is unclear. This is assessed by the pediatrician during the prevaccination examination, which is a mandatory action not only for problematic, but also for routine vaccinations.
If the pediatrician, after a thorough examination and, if necessary, skin tests, concludes that the risk of vaccination is significantly lower than the risk of non-vaccination, he may the perform vaccination under supervision. The full dose of vaccine is administered at one time, or graduated, in 2 steps 30 minutes apart. Surveillance lasts 60 min.