Practical experience of using pneumococcal thirteen-valent conjugate vaccine among premature infants

Aim. To ground the necessity of premature infants’ vaccination against pneumococcal infection and estimate the reactogenicity and immune activity of pneumococcal 13-valent conjugate vaccine when vaccinating infants with different degree of prematurity.

Materials and methods. The clinical study enclosed 88 children including 16 (18.2 ± 0.25 %) infants with extremely low birth body mass (ELBM) and 28 infants (31.8 ± 0.32 %) with very low body mass (VLBM). The mean gestation age was 31 ± 0.41 weeks. The mean birth weight was 1530 ± 66.58 grams. Bronchopulmonary dysplasia was diagnosed in 27 ± 0.25 % of infants. Thirty one infants underwent assessment of the concentration of the total level of specific blood serum IgG antibodies to S. Pneumonia antigens contained in vaccine. The mean age of these infants was 9.71 ± 0.74 months, the mean gestation age at birth – 30 ± 0.41 weeks (25 to 41 weeks). The mean birth weight – 1441 ± 66.58 grams, ELBM – 14 infants, VLBM – 18 infants.

Results. The mild general postvaccinal reactions were noted in 11.3 ± 1.24% of infants, which were arrested for 2 days with no drugs used. The moderate and severe reactions were observed in 2.27 ± 0.62 % of infants. No local postvaccinal reactions were registered. When studying the concentration of the total level of specific IgG antibodies to S. Pneumonia antigens, there was revealed a more than 4- fold increase in geometric mean of pneumococcal antibody titer that proves a high immunogenicity of this vaccine in premature infants. A high level of pneumococcal antibodies after vaccination was reached in 24 infants (75 ± 1.24 % of infants).

Conclusion. The necessity of immunization of premature infants against pneumococcal infection was scientifically grounded. The application of conjugate 13-valent pneumococcal vaccine among premature infants confirmed a high profile of its safety and high immunogenicity. Improvement of communicative habits between parents and medical personnel regarding the necessity of vaccination of premature infants against pneumococcal infection, as an advanced technology, will permit to provide a timely coverage of infants with immunization (98 %).