P256 Study of the tolerability of dtap vaccines in children after 4 years of age

Abstract

BackgroundPertussis is a highly contagious bacterial infection with a respiratory route of transmission. It remains an important public health problem in Russia and in the world. The only confirmed way of specific prevention of pertussis is vaccination. There is only one booster dose against pertussis at the age of 18 months with DTwP in Russia. This vaccine is not administered in children after 4 years of age due to its reactogenicity. The alternative way to the whole cell pertussis vaccination is the administration of DTaP, which can be used in older children.Aimsto study tolerability of vaccines containing acellular pertussis after 4 years of age.MethodsThe retrospective study included the analysis of safety of DTaP vaccines in 123 children aged 4–9 years from 01.12.2014 to 31.12.2015. It included 62 healthy children, 30 with allergic diseases and 31 with other chronic diseases.ResultsIn the post-vaccination period (3 days after the vaccination) local reactions were observed in 39 (32%) subjects, where 19 (31%) were healthy children, 11 (37%) – with allergic disease, 9 (29%) – with other pathology. Moreover, severe local reactions in the injection site occurred in 15% of subjects. Half of these children had different allergic diseases. Common reactions were observed in 25 (20%) children, where 11 (18%) were healthy, 6 (20%) – with allergic pathology and 8 (26%) children with other chronic diseases. Only 7% of the common reactions were considered severe. During the first week after the vaccination, no exacerbations of allergy or any other chronic diseases were observed.ConclusionA good tolerability of DTaP was demonstrated in children after 4 years of age in both healthy subjects and those having different chronic diseases. Apart from the children with allergic pathology who had severe local reactions more frequently, these two groups had no difference in the prevalence and severity of post-vaccination adverse reactions.