Dynamics (2014-2019) of Tetravalent Vaccines Against Meningococcal Infection Serogroups A, C, Y and W-135 Use: Prospective Study of Series of Cases Followed by the Monitoring of the Immunization Safety (Using the Conjugate Vaccine as the Example)

Background. Meningococcal infection (MI) is one of the most dangerous infectious diseases with high rates of complications and mortality, especially in infants. The aim of the study is to estimate the dynamics of the number of cases and safety of primary MI prevention with the use of polysaccharide and conjugated vaccines against serogroups A, C, Y and W-135 among the children’s population.Methods. Dynamics of tetravalent vaccines against meningococcal infection use was studied in the Centre of preventive vaccination at infectious diseases hospital (Krasnodar) among healthy children aged from 9 months to 18 years. The study period was from January 2914 to November 2019. Vaccination safety (conjugate vaccine as the example) was estimated according to the number and severity of local and general side effects developed within 30 minutes and 5 days after vaccination (maximum up to 10th day). Postponed side effects were recorded via phone survey of the parents.Results. During the study the number of vaccinated with tetravalent polysaccharide (n=264) or conjugated (n=944) vaccine against meningococcal infection increased from 79 patients in 2014 to 386 in 2019. The increase of the number of vaccinated people was associated with the implementation of conjugated vaccine (it was the only option in 2018 and 2019). After the use of conjugated vaccine, the local side effects were revealed in 20 (2.1%) out of 944 patients, 5 (0.5°%) of them had both local and general reactions. Meanwhile, all side effects were slight.Conclusion. Almost 5 times increase of the number of children vaccinated against MI with tetravalent vaccines in the period 2014-2019. Low incidence of side effects, most of which were local and slight, was noted