The purpose of any vaccine is to develop a body of post-vaccination immunity. It should be understood that the vaccine is a significant impact on the immune system of the body. In some cases it may take asymptomatic, in some manifest grafting reactions. Vaccination reactions are divided into adverse reactions and complications.
Adverse reactions and complications after vaccination is a reaction that occurs due to vaccination, but is not an obstacle to subsequent injections of the same vaccine. These changes can be unpleasant and uncomfortable for the child, but, as a rule, are part of the normal vaccination process. Adverse reactions are divided into local, occurring at the injection site (redness, tenderness, induration), and common, affecting the whole body – fever, malaise, etc.
In children vaccinated with live vaccines (there are live attenuated vaccines against polio, measles, rubella, mumps), to normal vaccination process also include the symptoms of those organs and systems that are affected in the corresponding infectious disease. For example, for measles vaccination, in addition to temperature and intoxication, characterized by cough, coryza, conjunctivitis , redness (hyperemia) of the throat, mumps is a short – term increase in parotid salivary glands, while vaccination against German measles – cough, runny nose, rash, joint pain. All manifestations of the normal vaccination process short and lasts no more than 3-5 days.
Unlike adverse reactions, complications of vaccination is unwelcome and sufficiently severe conditions arising after vaccination, preventing the re-introduction of the same vaccine. Vaccination complications are extremely rare, each case is logged and given to the public. This results in numerous opinions of the opponents of vaccination about the deadly risks for children.
Causes of postvaccinal complications in the majority of cases are not related to the composition of the vaccine, and in violation of the rules vaccination:
– failure to observe contraindications;
– violation of the rules and techniques of vaccination (wrong choice of place of administration of the vaccine, obinna true for BCG, which should be injected strictly intradermally);
– poor quality of the vaccine;
– violation of conditions of transportation and storage of vaccines (overheating, overcooling and freezing of vaccines must not be frozen);
– individual reactions caused by the vaccine (unexpectedly severe allergic reaction on repeated administration of the vaccine).
Most complications can be easily avoided by choosing a highly qualified pediatrician and vaccine quality. Even if the vaccination is scheduled at home, the doctor has every opportunity to observe a temperature mode of storage and transportation. Try to clarify the expiry date of the drug. The doctor must record the information about the vaccine name, lot number, expiration dates) in the vaccination card for the child.
The bigger problem are vaccine-associated disease in immunodeficient States. They arise from the introduction of a live attenuated vaccine to a person with immune deficiency. In population terms, these complications are very rare (1 in 1000 000 doses of vaccine). Immunodeficiency conditions imply as primary immunodeficiencies and secondary (due to treatment with corticosteroids, chemotherapy or radiotherapy). The exception is children with asymptomatic or clinically evident HIV infection, do not have severe disorders of the immune system (a CD4 count is slightly below age norms). These children can be vaccinated after blood tests and under careful supervision of a specialist.
After the introduction of live attenuated vaccines to people with failing immune systems may develop diseases such as vaccine-associated polio, measles or rubella encephalitis, and serous meningitis caused by vaccine virus of mumps.
A significant problem in this aspect is the BCG vaccine (live attenuated tubercle Bacillus, Mycobacterium bovis). In the absence of contraindications, it is conducted in a maternity hospital during the first days of a child’s life. However, even the most careful inspection does not reveal immunodeficiency condition at birth. It is therefore often postvaccinal complications after BCG are these children the first symptom of the disease. This can be a local inflammation at the injection site, swollen lymph nodes (lymphadenitis), lung disease or generalized BCG infection. Fortunately, in most cases, these conditions can be treated with antibiotics. In the future, the child is undergoing treatment for the underlying disease. Any vaccine-related complications after the administration of BCG vaccine can be symptoms of immunodeficiency States and require specialist advice.