Vaccination today is one of the methods of protection against infectious and viral diseases, including those that lead to serious complications. Thanks to vaccination, the human body learns to respond quickly if it encounters a pathology. The vaccine is an immunobiological drug, the action of which is aimed at the formation of immunity to diseases. It is produced from weakened or dead microbes, their waste products, or from their antigens. What is a live attenuated vaccine? It is worth looking into this matter.
Problem description
Attenuated vaccine is a live vaccine that is produced on the basis of weakened microbes that have persistent harmlessness. Once in the human body, microbes begin to multiply, which leads to the vaccinal infectious process. In many vaccinated people, the infection proceeds without symptoms and leads to the formation of stable immunity. Asexamples include an attenuated vaccine against rubella, tuberculosis, measles, or polio.
Possible Complications
An attenuated vaccine is one that is prepared from apathogenic infectious agents that are weakened and have lost their pathogenic properties, as well as the ability to provoke the development of a disease in humans, but they can multiply in the body.
The infection that occurs after the introduction of such a vaccine develops for a certain period of time, but does not show any symptoms, but it stimulates the formation of immunity to pathogenic microbes. Thus, the infection proceeds in a mild form, it activates the body's defenses.
But in some cases, a live attenuated vaccine provokes the development of pathology. This usually occurs when a person has reduced immunity or with residual virulence of the strain.
Today, five attenuated vaccines are used in medicine, these are:
- BCG - against tuberculosis.
- Oral polio - against polio (OPV).
- Rotavirus vaccine.
- Yellow Fever (YF).
- Attenuated measles vaccine.
All of these can rarely cause adverse reactions:
- BCG is a fatal (extremely rare) infection in people with immunodeficiency, as well as bone damage caused by certain batches of the vaccine.
- OPV – paralytic poliomyelitis (extremely rare).
- Measles - febrile convulsions (convulsions) occur extremelyrare in children under five years of age, as well as purpuric thrombocytopenia, an allergic reaction to vaccine components, anaphylaxis, which is a medical emergency.
- Rotavirus - no data on the development of adverse reactions.
- YL - encephalitis, vaccine-associated viscerotropic pathology (extremely rare) usually occurs in elderly people.
Safety
An attenuated vaccine is one that activates all components of the immune system, which provides long-term protection against infectious diseases. Since it contains live microbes, there is a certain risk of developing pathologies. Of course, the risk of the ability of microbes to return to a pathogenic form and provoke the development of the disease is quite small, but in extremely rare cases the following side effects may appear:
- VAPP or Vaccine Associated Paralytic Polio.
- Poliovirus.
- Local lymphadenitis, disseminated BCG infection.
- Retrovirus.
People with HIV cannot adequately respond to vaccination, the risk of developing adverse reactions in them is quite high. It is not recommended to vaccinate women during childbearing.
Attenuated vaccine is one that has a high risk of vaccine errors. Some vaccines, for example, are presented in dry powder form. They must be diluted with a special solvent before administration. In this case, physicians may make a mistake using the wrong diluent ormedication. Many vaccines require he althcare professionals to pay special attention to the cold chain in order to maintain their potency.
Thus, the risk of developing pathologies is as follows:
- The ability of microbes to revert to pathogenic form.
- Ability to use time for people with HIV.
- Risk of infections.
- Procedural errors.
- Vaccination during pregnancy.
Restrictions on the use of the vaccine
Attenuated vaccine is the one that is contraindicated in such cases:
- Period of bearing a child.
- Acute infectious and non-infectious diseases.
- Exacerbation of chronic pathologies.
- Immunodeficiency states.
- Cancer of the blood, the appearance of malignant neoplasms.
- Going through radiotherapy.
- Taking immunosuppressants.
- Prone to severe allergic reactions.
- Development of complications from the previous vaccination.
Conclusion
The fight against infectious diseases through vaccination currently remains one of the greatest human achievements in the field of medicine. Today, the prevention of infectious diseases is a powerful, safe and quite effective way to combat infections of various origins. In medicine, many vaccines are used, including live ones, which form a protection against many diseases, such as measles, polio, rubella, etc.
Today, WHO medical practice recommends the use of five attenuated vaccines. These are BCG (tuberculosis), OPV (polio), YF (yellow fever), rotavirus and against measles. With proper conduct and compliance with all medical recommendations, the risk of adverse reactions is minimized.
