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The varicella-zoster virus vaccine

The varicella-zoster virus vaccine


Varicella-zoster virus is part of the herpes virus group and produces 2 distinct diseases, varicella and herpes zoster.
Varicella is a disease that occurs in most cases in children (infectious disease of childhood) and usually has a benign evolution (not serious). Therefore, the administration of the vaccine that protects against contacting this type of infection is not always recommended.
Many pediatricians recommend active immunization of children (passing through the disease), as this is in most cases a mild condition. Immunization of this kind confers immunity that persists throughout life and prevents relapse of the disease.
The vaccine, like all vaccines, can have some side effects and does not usually offer long-term immunity (only for a few years).

However, there are certain population groups where vaccination is against recommended (adults or children with poor immunity, before immunosuppressive treatments, epidemics).
The varicella-zoster virus vaccine contains a live, attenuated virus strain and was approved for use only 15 years ago, although other vaccines have been used in the past.
Recommendations for the administration of varicella-zosterian vaccine:

  • immunocompromised children (with leukemias, those performing cytostatic treatments, immunosuppressants, malnourished children or other associated diseases) should be vaccinated, as they can develop serious forms of the disease
  • immunocompromised adults, young people who are receiving chronic treatments, immunosuppressants, pregnant women (vaccination before pregnancy about 3 months) must also get the vaccine.
  • The administration of the vaccine prevents the emergence of epidemics that can give rise to resistant, virulent strains and thus lead to serious forms of the disease.
  • avoidance of rare, but serious complications of varicella (pneumonia and varicella encephalitis have a high mortality of over 30-50%, being almost impossible to treat and which usually leaves the major sequelae or causes the death of the child.
  • avoiding the late onset of shingles, which can affect any age. Unvaccinated adults who have not had chickenpox in childhood have a risk of about 10% to clear herpes zoster with varicella-zoster virus.
    The varicello-zosterian virus can remain confined to the central nervous system and it can be reactivated whenever the immunity of the person concerned decreases.
    Herpes zoster is an extremely painful and unpleasant condition, difficult to treat and which recurs in most cases, is characterized by the appearance of bladder skin lesions (similar to those of chickenpox) and that appear along certain groups of nerves ( dermatomas), most often in the face and chest.
    The lesions are extremely painful because they are located on the nerve threads, can be generalized and superinfected if not treated properly (administration of Acyclovir, a powerful antiviral).
    Vaccination against varicella-zoster virus is recommended for all high-risk groups or healthy children, around the age of 12-18 months.
    Vaccine contraindications against varicella-zoster virus
  • allergy to other vaccines, allergy to some drugs (neomycin)
  • HIV infection, especially in the stage of AIDS (acquired immunodeficiency syndrome)
  • severe immunosuppression (oncological diseases, immunosuppressive treatments)
  • pregnant women
  • premature children, malnourished, children with other associated diseases (especially infections)
  • the presence of fever (the vaccination is postponed after establishing the etiology of the fever and its proper treatment)
  • severe thrombocytopenia of different etiologies (decrease in blood platelet counts) or innate or acquired disorders of immunity (gamapathies, immunoglobulinopathies, autoimmune diseases)
    Special attention to the administration of varicella-zoster vaccine is related to certain special situations that need to be carefully considered by the pediatrician.
  • febrile states secondary to common infections (colds, bronchitis, influenza, etc.), postpones vaccination with a few days to 2-3 weeks
  • the administration of steroid medication for a period of 2 years (anti-inflammatory and strong immunosuppressant), often used in the treatment of asthma in children, postpones vaccination up to 3 months after discontinuation of initial treatment
  • chemotherapy and radiation therapy used to treat cancer in children, delay vaccination up to 5 months after discontinuation of immunosuppressive treatment.
    This free interval is necessary for proper regeneration of the immune system, which must secrete protective antibodies upon contact with the virus (vaccine).
    Adverse reactions to varicella-zoster vaccine administration
    Of the adverse reactions that occurred during the administration of the varicello-zosterian virus vaccine, we mention:
  • pain, edema, erythema (redness) at injection level occurs in approximately 20% of vaccinated children
  • the occurrence of sub-fever (37-38 degrees celsius) or fever (over 38 degrees celsius) occurs in 10% of vaccinated children
  • the appearance of several bladder lesions of the varicella type, appears in a small number of vaccinated children (4%)
  • febrile seizures occur very rarely in less than 1% of vaccinated children and are usually benign and non-relapsing
  • more or less severe allergies (rash, laryngeal edema or even anaphylactic shock)
  • the onset of pre-existing but asymptomatic autoimmune diseases (more frequently in adolescents), is attributed to several vaccines, but is still in the study phase
  • there are an extremely small number of cases mentioned in the medical literature, of serious complications arising from the administration of the varicello-zosterian vaccine (encephalitis, varicella pneumonia) <